Traffic Safety & Congestion Impact Analysis

This assignment examines the complex interplay between traffic safety, congestion levels, and roadway design. Students are tasked with analyzing crash statistics, identifying contributing factors related to both safety and congestion, and proposing mitigation strategies to enhance road safety while addressing congestion issues. The analysis should consider various aspects such as speed limits, lane configurations, lighting conditions, and environmental factors.

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Traffic Engneering
Name
Institution

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Abstract
The future of the transport sector in Australia and New Zealand is expected to continue to
grow, due to the higher number of vehicles that are expected to continue utilizing the major road
networks on a daily basis. The rates of accidents have also been projected to increase and this
will contribute to delays on the roads, as well as traffic congestions and other incidents. These
incidents tend to disorganize the entire transport sector. The traditional approaches to these
incidents on the road transport system would not have worked because the time of an incident
would be multiplied and compounded by the time that it would take for an incident that has
occurred to be detected, prompting more delays. Then the time it would take for the response
teams to react and then the time that it would take the involved personnel to arrive at the scene of
the incident. Traditional methods would not be effective in in prudently dealing with the snarl up
caused during incidents, and this would affect the efficiency to keep the road in optimal
operation.
For this reason, a number of software packages have been introduced so as to resolve the
incidents that occur on the road and thereby effectively and successfully managing incidence and
thus the resulting traffic congestion. To achieve this kind technological based management, the
incorporation of Automatic Transport Management System can be utilized so that the impact of
incidents on the road network section and congestion in this area can be established and
managed. This is conducted through the mesoscopic and the microscopic simulation of traffic
across the case study area on Hoodle Street. These simulations are then used to emulate the flow
and movement dynamics of the vehicles moving within the entire transport network based on
specific models of the analytical predictive modeling tool used known as the AIMSUN tool. This
tool is thus able to consider the specifications of the AIMSUN model to emulate factors on the

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road such as the choice of route from one destination and the car-following and lane changing
movement so as to implement the dynamic flow of traffic on the model. The microscopic regions
are appropriate for the analysis of the operational aspects of that section of the road in the event
of an incident and the models require plenty of synthesized data to run. Mesoscopic areas on the
other hand mainly focus on the flow of traffic on that section of the road which also considers the
obstacles and intersection activity allowing a wider area to be modelled with high traffic
dynamics efficiency. The consistency of the results from the models is extremely important for
the accuracy and precision of the insights given from the model from the mesoscopic and the
microscopic model.
The paper looks into the manner in which SCATS imported models can be used for
incidence management and coincidence control together with AIMSUN as well as how SCATS
has been used in other developed areas as traffic control strategy and as incident management
tool. This is because SCATS is an adaptive traffic signal control system which uses real-time
traffic information to adjust the movement of vehicles in traffic and thus delay incidents and
manage congestion (Sullivan and Flannagan, 2012). In this case study, the real-time information
obtained from scats has been calibrated and validated to fit an AIMSUN model and the model
has been used to design a traffic management tool for Hoodle Street in Melbourne. An effective
incident management system will grant the existing methods of congestion control and incident
management more reliability in terms of the predicted time of travel and delays expected in the
roads, as the AIMSUN model will utilize an analytical predictive modeling tool. All transport
conditions on Hoodle Street on the modelled intervals and days of the week will be modelled and
insights will be generated to improve the incident management strategies used and thus show
how the incorporation of technology would be effective in improving the strategies for

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congestion control and incident management. Thus the tools will also be used to give
recommendations on how incident related congestion can be managed in the case study area of
Hoodle Street. The conveyance of information would also aid drivers to quickly adopt
instructions for diversion thus easing the demand for traffic and thus reducing the rates of
congestion on the roads. This will also improve the traffic safety and improve the compliance of
individuals to traffic rules and regulations.

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TABLE OF CONTENTS
1. INTRODUCTION...................................................................................................................................7
Traditional approaches............................................................................................................................7
Smart Mobility Technologies.................................................................................................................10
Current Gap in Modelling tools.............................................................................................................12
Aims.......................................................................................................................................................13
Objectives..............................................................................................................................................15
Case Study.............................................................................................................................................15
2. LITERATURE REVIEW..........................................................................................................................18
Incidents and Incident Management.....................................................................................................19
Incident Management Tools in Developed Areas..................................................................................23
SCATS in Traffic System Management...............................................................................................23
Analytical Predictive Modeling Tool..................................................................................................27
3. METHODOLOGY.................................................................................................................................31
Case Study Area.....................................................................................................................................31
Importing the SCATS for Hoodle Street Congestion Problem................................................................33
Theory/Calculation................................................................................................................................36
Types of Incidents Contributing to Traffic Congestion...........................................................................39
Accidents and Traffic Congestion.......................................................................................................40
Road Construction and Congestion...................................................................................................40
Roadside building construction and congestion................................................................................41
4. RESULTS.............................................................................................................................................43
5. DISCUSSION.......................................................................................................................................49
6. CONCLUSION.....................................................................................................................................52
7. FUTURE WORK...................................................................................................................................54
8. REFERENCES......................................................................................................................................56

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1. INTRODUCTION
The future of the transport sector in Australia and New Zealand is expected to continue to grow,
due to the higher number of vehicles that are expected to continue utilizing the major road
networks on a daily basis. The rates of accidents have also been projected to increase and this
will contribute to delays on the roads, as well as traffic congestions and other incidents. These
incidents tend to disorganize the entire transport sector. The traditional approaches to these
incidents on the road transport system would not have worked because they time of an incident
would be multiplied and compounded by the time that it would take for an incident that has
occurred to be detected. Then the time it would take for the response teams to react and then the
time that it would take the involved personnel to arrive at the scene of the incident (Abdel-Aty
and Radwan, 2010). Traditional methods would not be effective in in prudently dealing with the
snarl up caused during incidents, and this would affect the efficiency to keep the road in optimal
operation.
Traditional approaches
The role of managing traffic and implementing measures to manage incidents in the road
network system is to improve the flow of traffic during incidents which slow down traffic. Such
incidents include occurrences that would cause a snarl up of the movement of traffic such as
accidents, road works, and the constructions of private developments that affect the road usage.
An incident management system would also increase the effectiveness of the road system
networks through a reduction of traffic emissions and effectively utilizing the capacity of the
traffic network. This will help to optimize the traffic systems by curbing the demands of
transport in the city and also encourage people to prefer this mode of transport, the time taken to

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travel and the route taken, due to its improved effectiveness. Thus, for traffic to be managed
effectively, the information regarding traffic and any incidents within the network system has to
be clearly communicated, such as how to control the traffic, the occurrence of incidents and how
they can be managed. This in turn will look into managing the demand for the transport form, as
well as the support as well as the monitoring of the entire transport system.
The information about traffic in this incident management system is a very important feature of
the system, as it provides the system with real-time information for the users and also the
institutions associated with the management of the incidents that occur on the transport system.
This information includes weather news and conditions on the road ahead for the road-users,
schedules for the maintenance of the road or maintenance works areas of the road, occurrences of
any incidents on the road, the traffic information with regards to any incidents on the road and
where the snarl up is, as well as if it is advisable to take any other mode of transport instead. By
providing this kind of information, traffic can easily be controlled in the road transport network
system for every node which are the intersections (Qin, Ivan, and Ravishanker, 2013). This
means that the management system will thus be able to control the entire road network system
per for different sections, through a fixed or a dependent traffic control.
Incident management systems are specifically aimed at detecting any incidences in the transport
network, thus handling any form of traffic incidents and eliminating any possible risks of traffic
snarl ups as a result incidents. It also has to work hand in hand to with different authorities that
would ep to clear up the go slow, regardless of whatever kind of incidence has occurred. It also
involves the management of the demand for the specific transport mode, and thus the
determination of the flow of traffic route, mode, and even time of travel for many road users in
the city. The incidence management system can become successful if the traffic management

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system would be able to regulate access and parking in straight high-speed infrastructure and
organizing facilities for the residents where the road users park and ride. Other incidence
management strategies include carpooling and encouraging the use public transport to cut on the
number of vehicles using the networks, and promoting the cycling and pedestrian traffic (Wood,
2012) In addition, improving the passage of information between the road users and other
stakeholders of the transport sector is also a strategy for the management of incidences through
making use of road charges and tolls.
An effective incidence management system also has a monitoring system, such that ICT
solutions could be incorporated into controls like the automatic speed control and the intersection
control. This part of the incidence management system is utilized for the observation of any
hazardous materials being transported through the road networks. The monitoring systems could
also be used to monitor how the lanes are used automatically (Rock, 2015(. ICT solutions can be
incorporated in driver support systems where the driver is given suggestions by the incidence
management system on that route to give the driver assistance and thereby prevent the
occurrence of collisions, navigation, and helping the drive maintain in their respective lane. It
also includes the control, planning, and monitoring of the transport activity of a given vehicle or
a set of them, especially regarding their operations and movement as well as that of their drivers
(Koorey, McMillan, Nicholson, 2008). The incident management system will therefore only
achieve effectiveness if all the aspects of transport chain and its management operations have
been streamlined to adopt a lean system.
Road network where a strategic incident and traffic management system can be installed
is mainly composed of different components, such as the metropolitan sections, urban areas,
connecting sessions, main roads, basic road networks for rural sections, as well as special sites.

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The effective system can also only function to achieve safety and efficiency of the system
between the different regions that are connected in the network, so as to offer the other users as
well as good transport chain services, foreign exchange in all corners.
Smart Mobility Technologies
Incident management in the streets of Melbourne especially using smart mobility will be an
effective tool in dealing with incidents that would slow down the snarl up of traffic in the city.
This kind of solution will have to make use of the five pillars of incident management, where the
risk of any incidents will be minimized so that the roads can be returned to optimal functioning
road network system. A road management system that utilizes the concepts of smart mobility is
aimed at achieving a road network system that is uniformly functional throughout the entire city.
This is because the smart mobility technologies have created solutions for the most difficult
challenges in today’s modern cities where the road traffic systems have become the backbone of
the city transport system. In situations where the cities have been projected to grow as in the case
of Melbourne, it is expected that continuing to utilize the traditional approaches of road system
networks will elicit great levels of congestion(Abbas, 2013). The high levels of congestion is
also expected to bring in great levels of lawlessness, as it is difficult for any laws to be observed
when the systems being used are unable to follow errors and the roads operation is too
ineffective. The ineffectiveness would also lead to a diminishing of the funds that are set aside to
manage the city, while the conditions would continue to worsen.
Smart mobility methods for running a functional city like Melbourne ought to utilize the five
pillars of incident management using a collection of procedures that aims at enabling effective
operation on road transport networks as well as uses ICT enabled solutions to monitor the
movement of road users to ensure that law is observed. This would greatly reduce the amount of

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congestion within the city and thus enable the city acquire effective and optimal road transport
network systems. The solution will also have to holistically integrate the aspects of the
traditional approach with smart web technology optimizations to achieve a model that copes with
the pressure in Melbourne, which is expected to continue growing. It also ought to incorporate
the existing patterns of the road users in the city, and plan with the considerations of these
existing patterns and why they exist. In so doing, the incident management system will ensure
that the issue of traffic safety is tackled, while at the same time incorporate the patterns and
dynamics of the behavior of travelers in that city. It also ought to factor in the mobility culture of
the people of Melbourne as well as the environmental and mobility awareness of the people of
that city (Shankar, Mannering, and Barfield, 2015 ). The incorporation of Information
Communication Technologies will aid the smart mobility solution to incorporate many diverse
and more optimal solutions that will aid in managing incidents of whatever kind in the streets of
Melbourne.
The smart mobility solution for the management of incidents in the streets of the city of
Melbourne ICT and traditional approaches can be incorporated to yield an extremely effective
and optimal management system. For instance, making sure that the system introduced for the
city will have a system of programming and preplanning through the utilization of ICT solutions
would ensure that the incident management system is able to detect the occurrences of incidents
soon as they happen, to prevent the build-up of traffic as in the case of traditional approaches.
Traditional approaches usually take time before the occurrence of the incident is detected, and
then before the response systems are informed and they get to the scene with the necessary
equipment. It also requires the role of the traditional approaches to allocate the required
resources for all the systems to run effectively without any shortage. Communication between

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the different sectors of the road network system and the incident management system is
extremely crucial and is the third pillar of an effective incident management plan. This will
require an incorporation of the ICT solutions. The fourth pillars are building skills and capacity
for the people who will work in the different institutions while the fifth pillar is concerned with
managing and reporting of the incident management system.
Current Gap in Modelling tools
The most effective traffic management system will utilize an approach that incorporates ICT
solutions into the traditional approaches of traffic management, so as to yield very promising
results. For instance, to reduce the number of injuries and fatalities as a result of incident
management systems, both automatic monitoring of the road networks and the traditional
approach of the variable traffic control will aid to control the behavior of all motorists on the
road. To improve safety on the road, both ICT and traditional approaches can be incorporated
through the use of notifications of information for the drivers and road users through ICT and
providing information on safety and how it can be achieved in rest stops services. To ensure that
the people comply with all the traffic rule and regulations to prevent the development of any go-
slows, the intervention of ICT systems can be used in automatic monitoring of the roads to
identify traffic rules offenders and using a variable traffic control system for ensuring that every
sections of the road network system is functioning effectively and that there are no offenders in
the roads. Issues like the predictability of incidents can be effectively managed by
communicating to other road users the safety situations on the roads and through the
implementation of incident management strategies that are extremely beneficial and
workable(RTA, 2016). The reliability of the systems can also be guaranteed by encouraging road
users to pay up tolls and road charges which go into managing the system and ensuring it

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remains functional. Managing the occurring incidents would also help to improve the reliability
of the transport network. The incidents occurring can also be managed through suggesting
alternative routes after an incident has occurred and through the use of variable traffic control
systems to monitor the flow of traffic in that direction. Finally, the use of road use tolls and
charges could also be effective in managing the preference of people to use other modes of
transport and in constraining the growth of users of such systems.
Aims
A traffic management system will be effective in helping the traffic network in
Melbourne while at the same time striving to achieve the goals of the transport network systems
as well as trying to achieve the customer satisfaction rates that are acceptable. The management
system is also expected to be able to solve the road transport inefficiencies like the inefficiencies
of energy consumption and how this has contributed to emission issues and climate change, as
well as coping with elderly motorists who continue to age while using this roads and thus a
disregard for traffic rules and regulations. These problems have ailed the industry for too long,
thus contributing to the road network system inefficiencies that the incident management system
will try to solve. Problems on the main road network include the insufficiency of the behavior of
road users to adapt and suit road conditions that that help to reduce the number of incidents and
prevent them from occurring on the roads. In the dark periods and seasons like during the winter,
cases of low visibility affect te functionality of the road system which affects the speed people
are driving at and thus creating a snarl up on the road system. Yet another problem that would be
solved by implementing the incident management system would be a better command of
predictability regarding the insufficiencies that would take place on the roads, and this would
cause a surge in the use of other transport modes, thus an increase in the congestion rates within

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the traffic system. All these factors would sometimes also contribute to the high rates of unsafety
in the roads due to the usage and quality of different levels of road quality that are interconnected
within the road network system. This is because some of the roads within this network get
servicing and maintenance far much less than the main roads within the metropolis and urban
areas do, meaning that their levels and quality of the different roads vary. The incident
management system will also aid to manage the accidents and incidents among the cyclist and
pedestrian traffic, the poor functionality of the system which has also contributed to the
deteriorating conditions for all kinds of traffic and congestion and snarl ups in the road system.
In so doing, the problems of congestion and time wastage on transport networks and the risks of
injuries and fatalities as a result of incidents will thus also be significantly reduced by
implementing an incident management system.
The incidences on our major roads have been greatly associated with the most significant issues
within the public health system, where global road accident related deaths and injuries have been
associated with serious socio-economic consequences that hinder a nation’s development. The
reduction of incidents and the risks associated with incidents such as fatalities, injuries ad
congestion have all been designed by considering the five pillars of an incident management and
safety approach which intend to reduce casualties and congestion through incorporating a
functioning strategy management type. The management system will achieve all the expected
aims and solve all the impending problems through regulating the number of vehicles on the
roads as well as implementing strategies that will manage cyclist and pedestrian traffic. IT also
ought to factor in the incidents by providing care for victims of road crashes and ensure the
behavior of the road users serves to reduce the occurrence of incidents and thus congestion
(Abbas, 2013). An effective road management system aims to provide and effectively managed

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road system to avoid congestion from different incidents, and ensures that the road network
remains safe and efficient as possible. |It also aims to ensure that the road users and their vehicles
are safe to share the road facilities with other users without causing any incidents, and having a
reliable and efficient incident response and management system to prevent the build u of traffic
even when these incidents occur. The incident management system that Melbourne will
implement will increase the responsiveness of emergency teams to any incidents detected on the
road network system of the city, while also improving the health of other aspects of the facility to
prevent inefficiencies and incidents.
Objectives
This objective of using traffic management systems is to give the control of all road
sections to the management system, and thus ensure that the users of the transport system have
information regarding the speed regulations warnings about the occurrence of any incidents as
well as providing road users with guidance for the easiest way to get to their desired destination
without encountering any inefficiencies in the road system The system will also aid to track the
energy inefficiencies and the greenhouse gas emissions in that road network, to monitor energy
inefficiencies and how congestion and incidents on the road are related. This also makes it easier
for the system to be utilized in managing congestion from the simple management of incidents
like road accidents or even road maintenance or building works. This then means that the
environmental problems and concerns in Melbourne can thus be managed using a methodology
that constrains the demand intervals on the road transport network and the reduction of incidents
on the roads that are contributed to by the road incidents and disruptions.

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Case Study
Hoodle Street is a major street in the Hoodle Highway in the city of Melbourne, which
links the Eastern Freeway of the city from Fitzroy with the City Link in Richmond. The street,
which is joint to Punt Road to form Hoodle Highway, is faced with a serious problem of
congestion and traffic management. The road is commonly known to be clogged with traffic
especially during the peak hours of the day when most people are using the roads and the
transport system is occupied to its full capacity. This is because the street connected the city with
the inner suburbs of Melbourne city. In addition, because it is the best access point to the
Melbourne Cricket Ground which is the city’s main precinct for sporting and other events, it is
always highly congested after such events. The street has four lanes and serves a unique role as
it is the main connection point between the South Yarra district, St. Kilda within the city center,
the Marine Parade and Barkly Street. The street can thus be considered as the major arterial road
that connects the Melbourne CBD to the eastern part of central Melbourne. Its role in the road
system of Melbourne includes connecting people with the CBD where most citizens work and
conduct business and promoting the flow of traffic away from local roads into highways that
connects the CBD to other places.
The high rates of congestion in this street affect the Melbourne economy as it fosters the
low rates of productivity within the city through the reduced level performance and a decreased
access of social amenities to the local Melbourne community. Studies conducted in this street
have shown that more than 330, 000 people use the street on a daily basis, through different road
transport means including walking, bike riding, driving, and even making use of public transport
means. The increased rates of congestion can also be attributed to the higher rates of occurrences
of incidences on this road. Thus incidence management systems would come in handy a great

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deal to help ease the congestion noticed on this road and thus improve operation and efficiency
of different resources within the road transport network. In addition, incidence management on
this road will also be effective as it will ameliorate the safety state on this road, thus helping the
street to achieve an optimal flow of traffic, An incident management system on this road will
also help to manage the traffic of pedestrians and cyclists that also utilize the street. This will
also result in the reduction of cases that cause incidents which in turn foster the development of
serious cases of congestion.
.
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2. LITERATURE REVIEW
The expected rates of traffic congestion in Melbourne are expected to continue increasing due to
the numbers of incidents in traffic systems also rising. These incidents include the breakdowns of
cars and the rates of crashes within the road transport system of Melbourne as well as any forms
of construction or maintenance works that affect the usability of roads in different sections of the
roads network systems. These incidents contribute to as go-slow in the rate of flow of traffic
within the city, and thus the management of congestion and the occurrence of incidents requires
a sustainable and innovative solution that incorporates both ICT solutions and the traditional
approaches to yield an effective and reliable system for the management of incidents on the
roads (Al-Ghamdi, 2012). To develop this kind of an incident management system, the
congestion rates that are expected for large urban cities like Melbourne, so that the system can
focus on reducing the number of delays on the traffic network and thus accommodate the
capacity of people using the road network system at any given time.
Incidents have been understood to cause delays, especially when the capacity of the road system
is fully occupied or near full occupation. Thus the management system that have incorporated IT
systems to increase their intelligence and accuracy to improve the control of the system in
determining the capacities at which the roads are functioning, and thereby correctly direction
motorists to make use of alternative routes. This will go a long way in easing the pressure of
operational capacities of the road facilities in the city, thus ease congestion and prevent the
occurrence of more incidents on the roads. This will also have a lasting impact of reducing the
risks associated with these incidents, including fatalities and injuries related to crashes that occur
within the road transport networks ( Brockfeld, Kühne, Skabardonis, and Wagner, 2013). It also

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reduces any costs and inefficiencies that are incurred as a result of traffic congestion and the
related environmental issues.
Incidents and Incident Management
According to Shrank and Lomax (2009), congestion can either take place in a recurring
and a non-recurring manner, such that the recurring congestion takes place of a daily basis while
non-recurring congestion is the unexpected congestion on the roads as a result of incidences that
cause a delay in the travel time of motorists on the road network system. Incidences thus cause
an increase in the demand of road transport network facilities, and thus increase inefficiencies in
the use of the transport network and in the resulting delays and issues in the use of these
facilities. Due to the frequency of occurrences in incidents in different section of the road
network system, the role of incidences in the development of congestion especially during the
peak hours when the networks is operating at full capacity or slightly below it or slightly above
it. This is because; incidents slightly impair the capacity of the road systems and thus cause a
delay in the system as is experienced by the motorists. The existence of any available capacity on
the road network would aid the network top cope with incidences, although this is not true for a
road network that is near full capacity like Melbourne roads during the peak hours. This makes
dealing with incidences that have caused time delays to be a challenging situation for the city
personnel, affecting effectiveness of the transport system.
The delays that occur during traffic congestions brought about by incidents on the road are also
further affected by different factors that impact the length of time and the amount of delay that
motorists can face in such incidences (Bedard, Guyatt, Stomes, and Hirdes, 2012). For instance,
the time that the relevant response teams would take to detect the occurrence of incidences in the
entire road transport network of Melbourne would have a great impact on how long the traffic

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congestion would stay for. This means that the relevant authorities ought to have their eyes and
ears on the ground, to ensure that any incidences are detected and resolved in the shortest time
possible and thus allowing for the flow of traffic to resume normally in the shortest possible
time. Using a detection methodology that is not as fast would only worsen the delays that
motorists in the road network of the city experience and thus affect the duration and amount of
congestion experienced in the city.
An incident mainly refers to any event slowing down the movement of traffic within the road
network system of a city. These include road crashes and accidents, the construction and
maintenance works of a part of the road or even the construction of other infrastructure that
would affect the movement of traffic within the city. As such, the duration of some incidents
could also impact the amount and duration of traffic snarl up and congestion. In cases where the
go0slow is as a result of incidences that would take long, the delays expected on the road
systems are also expected to be extremely increased, since the flow of traffic will continue at an
extremely slow rate or even stoop completely until the incidence has been resolved and cars can
continue utilizing the roads in the expected rates of flow (Amoros, Martin, and Laumon, 2012).
In the event that the incidences that are taking place would slow down traffic for long periods, it
is important that drivers are informed at early stages in their journeys, so they can opt for
alternative routes and thus save themselves the agony of being stuck in traffic congestion related
time delays.
The time of day when the incidence occurs also has a great impact on the amount of
congestion and the level of delays within the transport network system. For instance, the road
system functions well within its full capacity in most parts of the day but increases during peak
hours when people are leaving work or school and in the morning when people are moving

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towards their workplaces. This upsurge in the capacity of the transport system is reflected in the
event of any incidences, as the delays caused will affect more road users in the peak hours than it
would in the off peak hours. The level of congestion in the road network is thus greatly affected
by the time of day the incident occurs, as the capacity of the roads varies in Melbourne at
different times of the day. This means that incidences occurring at off-peak time of the day will
result in delays that take less time in comparison to the traffic congestion delays that occur as a
result of the incidences taking place in peak hours (Austroads, 2009). The severity of the incident
also contributes to the amount of congestion and the length of the time that motorists will have to
sit in traffic within the road network system. This implies that when the incidence is more severe,
more equipment and personnel will have to make way to the incident site so that the situation can
be resolved before the road network system returns to normal functioning of the road system.
The reverse is also true for minor incidents that can be easily cleared up and sorted quickly, to
return the road network system to contain the users of the roads.
For the congestion problems to be resolved in the city so the road network continues to function
in the expected capacities, there ought to be parallel and alternative routes with a spare capacity
to take in more traffic flow and allow people to reduce the delays they encounter due to traffic
congestion (Karlaftis and Golias, 2011). Having alternative routes that function in parallel ways
with the main transport route network system is very important to divert the delays in traffic and
the congestion on the roads to ease up the transport system demand, although the alternative
routes also ought to have the required capacity for the main road system to fall back on, if any
incidents result in the development of traffic congestion within the system. Alternative routes
will ease the demand of transport network and also the capacity of the main routes in the event of
any incidences, thus helping to reduce congestion in the city transport road networks. Having

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able capacities of alternative routes will also enable the city transport network to restore the
capacity of the traffic network, as diversions can be made to the transport network to ease the
demand for transport and the delays resulting from incidence related congestion.
The management of incidences is important because it helps to reduce the congestive impacts of
the incidents on the traffic network of the city. A good plan will include both the traditional
approaches and information communication technology solutions, which will ensure that the
traffic systems are well monitored and incidents are managed and responded to in time. The
incident management system requires the system to detect and verify the occurrence of any
incidences. This can be achieved through CCTV and detection of any incidences that occur in the
transport road network. The information technology solutions can be incorporated into the
systems by giving information to road users and also to the response teams to achieve faster
response time to revert the congestive impact of incidences on the roads (European Conference
of Ministers of Transport (ECMT), 2012). Information can be passed through the VMS signs and
therefor serve the purpose of alerting road users about any incidents or even directing them to
take the parallel routes due to the congestion caused by these incidents. These ICT solutions can
also be incorporated into the traffic system through their insights in managing the scene of the
incident and controlling traffic around that area, as well as the recovery and the clearance of the
traffic network to restore a smooth flow of traffic in that city. In addition, the installation of web
based computer solutions such as the installation of loop detectors to detect incidents and verify
hearsay about their occurrence through the incorporation of algorithms for the automatic
detection of incidents on the road transport system. Further, the signal control of the entire
transport system could simply be automated, to enable a definite identification of the additional
capacity to carry traffic in the event of any incidents that would snarl up traffic (Jones, Janseen,

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and Mannering, 2011). This would thus prompt all the road users to give a priority to ambulances
after the occurrences of incidents, and thus the incident can be clearly reorganized and the traffic
system can return to normal operations before the capacity of the diversion routes is bypassed.
Incident Management Tools in Developed Areas
SCATS in Traffic System Management
One of the most effective incident management tools that can be utilized in Melbourne is the
SCATS tool which adds the capacity of route diversions when there is an incident ahead of the
road. In so doing, the tool is able to reduce the travel time of the motorists on the road, and thus
reduce transport system inefficiencies, as well as the environmental issues associated with the
menace of traffic congestion and the occurrence of incidences on the roads. The tool is able to
reduce delays especially in times when the traffic system of the entire system is being utilized in
high capacities, for instance in peak hours of transport system utilization. In such situations, even
a small reduction in the capacity of the road transport network system will be greatly affected as
the roads are heavily depended on by thousands of people (Martin, 2012). This results in large
delays and great differences in the times people take to travel, and thus an increase in
inefficiencies in the utilization of traffic systems as well as a great build up in environmental
issues.
A specific tool, SCATS, (Sydney Coordinated Adaptive Traffic System) is well renowned in
other parts of Australia and New Zealand like Melbourne and Auckland for the management
traffic systems. This tool was developed by the RTA (Roads and Transport Authority) from New
South Wales. This tool allows for the real time management system for traffic through the use of
stop line detectors in vehicles to identify any differences in the demands within the transport
system, allowing the traffic to be managed by trying to adapt in accordance with the signals

Traffic Engineering 24
produced in the system (Schrank and Lomax, 2013). This tool also utilizes the split plan in order
to establish the sequences of the phases within the system, and thus identify special features
within the traffic network such as tunnels and bridges. On the other hand, the cycling plans
within the road system is also used in SCATs but with the aim of establishing the time taken to
complete one cycle within the system, as well as to set the benchmark for the least possible time
one cycle can take and the least number of times that cycles can be conducted. The tool also
utilizes link plans which are responsible for the task of specifying the type of an offset that
should be allowed in the traffic management tool for road intersections that are adjacent to each
other within the road network system.
Other detectors utilized in the SCATS tool include the line loop detecting tools which
measure the rate at which traffic flows and how occupied the road network system is occupied to
its capacity. This then allows the tool to compute the degree of saturation within the SCATS tool,
which is a value that is used to quantify the level of green time that vehicles within the system
are utilizing. The split plans within the system are also effective for traffic management as a few
of them are set apart and attuned to match the degree of saturation value and this is a strategic
approach of management used in the system, utilizing both IT and traditional approaches. The
cycle plans within the system can also be attuned to ensure that the value of the degree of
saturation is maintained at a lower level than the capacity of the road network system on the days
when the strategic approach is the worst. The system functions determines the real-time
information for the SCATS tool through the use of stop lines installed in vehicles and link plans
being linked to the intersections in the entire road network system. As the tool continues to adapt
the commands following the differences in the demand for the transport system, it allows for the
road users to cope with the demand differences that are promoted by incidents on the roads. This

Traffic Engineering 25
not only makes this tool an effective method of dealing with traffic demands but the fact that the
tool provides real-time commands would specifically aid Hoodle Street in Melbourne.
The SCATS tool is only limited by its affinity to maintain the value of the degree of saturation
within the transport system in all levels. Thus, this may require the city to look into the
intervention of other incident management strategies to prioritize to diversion routes since even
the side streets of such diversion roads may also experience delays as a result of mismanagement
of time during incidents. In addition the SCATS tools also have a slightly gradual way of
adapting to any differences in the demand for the system. This is quiet desirable during the
congestions that have not been developed by incidents on the road network systems. When an
incident is detected using SCATS the operators of this traffic management system could SCATS
while anticipating the differences in the demand for the road transport system, and thus the entire
transport network will be prepared for the emergence of increase in demand for the diversion
routes and thus their capacities also have to be checked (Olstam and Tapani, 2004).
As an incident management tool, SCATS has different features that can be used for detecting and
for the management of incidents on the road networks. For instance, the tool would be effective
in the management of cases of an unusual traffic upsurge through the monitoring of the traffic
flow and configuring the information from the system to identify when the traffic flow rates will
be higher than the expected rates at any time within the system. The tool achieves this by
considering the different lanes on the road to be completely congested when the value of the
degree of freedom within that system is a high value and the rates of traffic flow as is detected by
the flow over detector of the tool is not as high as the value that would be expected (Bonneson
and McCoy, 2007). As such, the SCATS tool will not be able to identify any queues since the
detectors will be used at the stop line detections. This thus manages the unusual types of

Traffic Engineering 26
congestion through understanding that the congestion is as a result of queuing on the downstream
side and the effect of this is blocking more cars and traffic. Thus the SCATS tool monitors the
time period a lane on the road is unusually congested. To establish the status of congestion as
either an unusual or a usual condition through setting the expected times for the flow of traffic
through a congestion monitor such that the achievements of these expected times cause the
display of the next intersection in the road network system to appear in the congestion monitor
that marks unusual cases(Al-Ghamdi, 2013). This tool can thus be taken to be an effective tool
in establishing the time that the unusual congestion is expected to last for and thus the expected
amounts of congestion can be established ad anticipated from a given incident.
The tool also presents many routines for the variations in traffic management for different cities
and this can be used customize the signal operations in the intersection points of the entire road
traffic network. This ensures that the individual priorities of the specific region are considered in
the incidence management system of that region. For instance considering the SCATS tool
calculations of identifying and managing unusual congestion within the city can be customized
to make variation routines to test for the best approaches and the congestion. The intersections
parameters can also be altered to carry out tests on the management system and thus manage the
rates of congestion (Kam, 2012). Another feature that can be incorporated into the SCATS tool
to manage a city is the Action list routine which can be helpful in devising specific alterations to
the functioning of intersections within the road network system. For instance, alterations to the
functioning of specific intersections can be effected into the split plan or even cycle time of a
given intersection and thus action lists can be used to effect these changes by factoring in the
concept of the capacity of the transport network and the time of the day, by way of the SCATS
scheduler. Variation routines could also be implemented to achieve any differences in these

Traffic Engineering 27
aspects of the intersections. The action lists procedure is could also be helpful in the event of a
diversion due to any congestion brought about by any incidents in the road network. This is
because a number of associated and sequential actions could be modified to cause to prioritize
the alternative routes where traffic will be diverted to ease the congestion on the roads. Such a
collection of actions can only be effected into the system after an incident has been detected on
the road and is expected to snarl up some unusual congestion (Yau, 2013). By implementing the
different techniques offered by a SCATS tool to manage traffic in a city, unusual cases of
congestion that are usually spurred by the occurrence of incidents on the roads can be detected
early enough in advance by utilizing a congestion monitor tool and after the congestion has been
verified, the use of action lists and variation routines could be incorporated to prioritize traffic
management within the diversion route.
Analytical Predictive Modeling Tool
After the emergence of technology based transport management systems, new challenges were
developed regarding the traffic modelling systems that have positively contributed to improved
approaches that factor in very intricate details to emulate the exact conditions and dynamics of
travel for cars. The new intellectual transport management systems are able to give detailed
representation of the road network considering how cars change lanes, and how much gap
between the cars is acceptable in the different models especially considering the theories of the
flow of traffic and the models that have been devised to emulate the choice of routes. These
models are then incorporated into complex traffic modelling systems to replicate the dynamics of
traffic and its flow, thus attaining an effective model to contain it. This also enables the traffic
management systems to explicitly account for traffic and its control and thus makes it very
appropriate to analyze the functionality of the intersection. The effect of this is the ability to
allow the modelling of large road networks whose competency of efficiency to give the

Traffic Engineering 28
management system insights in the strategic planning for the management of traffic(Kochelman
and Kweon, 2012.
The use of analytical predictive modeling tools allows for the traffic system to be modelled and
analyzed following the guidelines of the strategic approaches of managing traffic through
focusing on the traffic flow of a specific area which is part of the entire network. This therefore
allows the management system to consider any of the diversions being made from Hoodle Street
to ease the area of the demand for the transport network and the full capacity operation on the
road (Shankar and Mannering, 2006 ). This is because congestion result from incidents that
actually increase the demand for these facilities and the full capacity operations of main roads
and the arterial roots that are used as alternative diversion routes of this entire system. The
ATMS systems also allow for the simulation to model a fraction of the trips that begin and end
outside of the specified area in a manner that ensures that these models are diverted into the
alternative diversion routes and thus a mesoscopic simulation of the entire road network but a
microscopic simulation of the specific area where modeled results will reflect.
AIMSUN is a well renowned simulation tool which is presented as a software from the
TSS and recommended by FHWA. According to this institution, the calibration and validation is
done by considering the least possible parameter numbers for a repeated number of times using
values that have already been calibrated and computed before utilizing the synthesizes data, so as
to achieve the best results from the simulation model(FHWA USDOT, 2009). The tool for this
reason has a fewer number of the parameters that can be modelled compared to other simulation
tools like SCATS, PARAMICS, VISSIM and MITSIM. This tool specifically factors the number
of parameters that would be significant contributors to incidents, including the ability to change
lanes, acceptance of the gap allowance for changing lanes, giving way, and overtaking. The

Traffic Engineering 29
model also factors in the speed and the position of the vehicle as it is moving within the road and
in relation to the movement of the other cars. It also considers the changing of lanes as well as
the application of car following model known as Gipps. The Gipps limits the drivers ability to
brake and thus allows the car to maintain a safe distance in relation to the adjacent cars, which
controls the acceleration and the braking ability of the car behind those preceding it, thus
avoiding the occurrence of incidents. Other than the prevention of incidents, this model is able to
assure continuous flow of traffic within the city and on that specific part of the road. The Gipps
model is also able to control the flow of traffic and thus manage congestion through constraining
the speed of a car in the next time step considering the speed the cars ahead of it are moving in,
thereby managing the congestion and preventing the occurrence of incidents (Gipps, 2016).
The AIMSUN tool is also able to reduce the number of variables and parameters that ought
to be considered so as to reduce to a minimum the number of factors that could encourage the
occurrence of errors as one is modelling for the management of incidents. Some of the
parameters that can be considered include the maximum desired speed, acceleration and
deceleration in the event of an incidence (TSS, 2012). These parameters aid to put in the right
considerations for a car traveling within the network at any point and time. These parameters
help the AIMSUN to model changing of lanes within a road network and the level at which cars
are following each other to establish the expected time of travel even during an event and
behavior of the network to discharge the car following queues within the road network. Other
parameters considered by this incident management tool that uses analytical predictive modelling
to predict the situation on the roads and thus effectively manage traffic include the acceptance
and limits of speed within the city as they affect the algorithms used to factor in the car following
rates and queuing discharge. While this parameter could always be adjusted in the model to

Traffic Engineering 30
better suit the case study, this specific case worked perfectly with the default values of the
AIMSUN tool.

Traffic Engineering 31
3. METHODOLOGY
In this specific case study, the methodology that was used to devise an effective incident
management tool for Hoodle Street in Melbourne was the analytical predictive modelling tool.
The selected method required that before the analytical predictive modelling tool was used, a
multi-layered Aimsum Model of the required section of Melbourne had to be developed. The
developed model would then be used to make a build of the Predictive Analytical Model. In this
specific case, this was achieved by following through a series of steps. These steps started with
the selection of the area for which I would be coming up with an incidence management system.
The next step was importing the strategic model of the area that was selected. This was then
followed by the process of importing a SCATS database of the same area which was then
calibrated and validated to suit the predictive modelling tool. The results of the Predictive Traffic
Modelling tool were then developed using the Aimsum Traffic Modelling System (ATMS).
Case Study Area
The study area that was selected was chosen focused on reducing the complexity of
computations, through modelling a specific area within the greater Melbourne metropolis. The
case study area was thus selected to be te area to the south eastern region of Melbourne CBD and
is shown in the figure below.

Traffic Engineering 32
Figure 1. Case Study Area of Melbourne showing the Microscopic and Mesoscopic Regions.
The area also appeared to be a preferable location when compared to other areas due to the
convenience of the major arterial roads in the area. The arterial roads seemed to have emerged
from the Princes and Nepean Highways and from the M1, also known as the Monash Freeway,
and Punt Road. The presence of these arterioles make the selected case study area an ideal
location to test the smart mobility solutions that could aid to ease the congestion in this area
while still limiting the space and the external factors that could affect the results. To further
simplify the complications of the modelling and importation processes, the area was further
broken down into two smaller regions depending on the type of simulation that was

Traffic Engineering 33
implemented for each region. This categorization is also well illustrated in Figure 1 above
which shows that the region to the north of the case study area was simulated using
microsimulation and the southern area was the mesoscopic simulation area. The
microsimulation area concentrated on Hoddle Street especially between the Eastern and
Monash Freeway. It incorporated 25 SCATS intersections with data coverage. The mesoscopic
simulation area, on the other hand, was on the south of the M1 and incorporated 134
intersections with SCATS data.
Importing the SCATS for Hoodle Street Congestion Problem
As the busiest and major arterial rod connecting the Melbourne CBD to other important
parts and amenities of the metropolis, the congestion rates on Hoodle street can only be corrected
by utilizing innovative solutions that factor in ICT concepts and new technology to ensure that
the entire capacity of this street is dedicated at helping people to move around the city as they go
about their business(Larsen and Kines, 2012). SCATS could be a very effective tool in assuring
the street of continuous flow of traffic, as the tool is able to detect incidences and unusual traffic
then manage the congestion through various ways. SCATS can thus be utilized as an incidence
management tool on Hoodle Street. Incidents ought to be modelled and simulated to identify
how the tool would help to optimize the movement and flow of traffic to ease congestion on that
specific street.
Simulating and modelling the street will help to ensure that the effect of incidences on the
roads which could affect the management of the flow of traffic and thus cause congestion is well
evaluated and the expected result used to identify incidences and thus aid to make the expected
adjustments on the system to ease the traffic (Fitzpatrick and Balke, 2015). Simulation also helps
to factor in conditions that cannot be established in the real world, unless a real incidence occurs.

Traffic Engineering 34
Simulating these conditions thus allows the system to test for different aspects and thus
accurately evaluate the effects of incidents occurring on a transportation network as well as the
different strategies that could be incorporated to ease the impact of these incidents on a street like
Hoodle Street. In addition, a calibrated model also has to be utilized to model the incidents that
could take place within a section of the road network system. The model produced was then
linked to the SCATS tool using its sim, and all of the signals that the system needs to project
within the tool were entered into the control of tool (Abdel-Aty and Adelwahab,2013). The
incidents were then modelled on the SCATS tool model of the road that is being investigated.
Some of the vehicles modelled on the tool were also diverted onto other alternative routes using
the variation routines and the action lists used in the SCATS management tool. The diversion
was done on all the vehicles headed east towards the suburbs using other smaller arterial
diversion roads that are bound for the eastern direction. Another diversion was also done for the
cars heading the opposite direction into the CBD using different arterial roads for diversion
(Shankar, Milton, and Mannering, 2007). In so doing, the SCATS tool as an incident
management system was used to model the following situations to make the inferences regarding
incident management Hoodle Street. The SCATS models obtained were then calibrated and the
validated to match the specifications of the ATMS tool.
To achieve a incident management using SCATS, the system models the best traffic flow
scenario that occurs when there are no incidents that have been factored in. It also models the
situation on the road when there were incidents on that specific road; such that traffic is diverted
to an alternative road (Hogwood and Gunn, 2014). The tool is then left to adapt to the
differences in demand gradually as it is normally to model a scenario with an incident using the
original SCATS recommendations. Finally, the incident is modelled when there were incidents

Traffic Engineering 35
on Hoodle Street and motorists began to divert out of this highly congested road to other arterial
diversion routes. Since diverting many cars would increase the demand of transport facilities and
reduce the functioning capacity of these other roads, a modified SCATS model was utilized. This
is achieved through altering SCATS at the intersection points on the road network system and
the intersections around the Hoodle Street area so as to prioritize the demands of the alternative
diversion routes ( Sabatier and Mazmanian, 2009). This helps to model the occurrence of an
incident on the streets and then modify the SCATS to achieve a balanced congestion rate on
these routes due to the sudden increase in demand for these routes.
For the diversion routes in the SCATS model to be prioritized, alterations have to be made on the
SCATS tool manually, so as to factor in the period of time when there was an incidence. These
alterations made are important as they help the system to factor in concepts of demand and time
of day to predict the best strategies of incidence management, and thus a chance to manage
unusual congestion due to incidents on the roads. Some of these changes include making
alterations to the split plans of the SCATS on that street, so as to increase the amount of time that
the green lights are on, and thus allowing more vehicle to pass on these diversion routes to
reduce the demand and pressure of congestion on the diversion routs (Hall and Cummins, 2009).
The effect of this is that the capacity of the diversion routes is kept lower and thus congestion on
the arterial diversion routes and on the main street is reduced. In addition, increasing the cycle
times also allows for cars on both the diversion routes and the main routes to pass through the
traffic network and thus ease transport system congestion as a result of the incident. When the
incident situation has been resolved, the cycle times can thus be toned down slowly, to return the
operations on the roads to normalcy. The final change that can be done to the SCATS at the
intersection point to reduce the demand for the transport system and thus reduce congestion as a

Traffic Engineering 36
result of an incident would be to change the linked intersections within the arterial roads that
function as diversion routes(Carson, Jodi, and Mannering, 2011). This would also help to
manage the incident and reduce congestion and the demand for the transport system network
especially in the diversion routes as the intersections between the main road in considerations
and the different diversions will allow for traffic flow and thus a reduction of congestion.
Theory/Calculation
After the multi-layered model obtained was calibrated and validated, it was time to build
the analytical predictive model. The number of patterns crated to model the typical situations of
traffic in that specific street sampling the situation of a weekday example and the two weekend
days as the reaction of the traffic is different. These three different patterns created to represent
the typical scenarios of the traffic congestion on Hoodle Street on an average weekday, a
Saturday and a Sunday. The patterns then incorporated the sliced 15-minute matrices from the
macro and departure adjustment and then applied them on the tool to reflect the results of a 24-
hour period. The information obtained at this stage of the tool was used to calculate the mean
weekday traffic profile following insights from the RDS of on Tuesday-Thursday. These days
were selected out of the other weekdays because those days provide the most consistent traffic
flows using this street. This mean weekday traffic profile was used for the purposes of explaining
the reasons for the differences in the matrices and the routes used during the entire 24 hour
period. In this model, the mean weekday traffic profile was also divided into five different
intervals namely the Pre AM (midnight to 7 am), AM (7 am to 9 am), Off Peak (9 am to 16 pm),
PM (16 pm to 18 pm) and Post PM (18 pm to midnight). Figure 2 below illustrates the profile of
the demand of the transport network system by road-users around the Hoodle Street area. It
utilizes the 15 minute matrices that are offered in te predictive model. In addition, the simulated

Traffic Engineering 37
model for the mean trafic profile for Saturday utilizes three different intervals fr the 24-hour
period, starting from midnight to 8 am, 8 am to 8 pm and 8 pm to midnight. This information is
demonstrated in Figure 3. On the other hand, the mean traffic profile for Sunday utilizes three
intervals for the 24-hour period, although these intervals are different from those of on Saturday,
due to the differences in the traffic patterns and expectations of incidents. The intervals for the
mean traffic profile for Sunday are from midnight to 9.00am, 9 am to 9 pm and 9 pm to
midnight.
Figure 2. Average Weekday Profile with 15-minute matrices for 24 hour period.

Traffic Engineering 38
Figure 3. Saturday Traffic Profile with 15-minute matrices for 24 hour period.
Figure 4. Saturday Traffic Profile with 15-minute matrices for 24 hour period.

Traffic Engineering 39
The servers used for simulation were configured to be into the analytical predictive modelling
tool using data that has been synthesized. The users of such a platform can benefit from
specifying the duration of the simulation for any given day or for a specific period of time, if the
required data is for a set period of time. This server therefore uploads the given matrix sets as
well as the APA files of the case, so that the specific required time period can be simulated. The
achieved simulation will therefore run if the specified simulation time. This is the reason why the
specified time simulations were run on the Mesoscopic experiment. The analytic predictive
modelling tool simulation is also characterized with the functionality of validation. This
functionality enables the results of the simulated model to be compared to the results that have
been observed from the RDS (Lee and Mannering, 2012).
Types of Incidents Contributing to Traffic Congestion
Traffic incidents refer to any scenarios that may contribute to a disruption in the normal
flow and movement of traffic on the roads, which cause actual and physical impedances and
obstructions on the different lanes of travelling that make up the road (Larsen and Kines, 2012).
Examples of common incidents that contribute to the development of traffic congestions include
road crashes, the construction of buildings and other personal development construction projects
which may affect a given section of the road and thus cause obstructions, the maintenance and
servicing of roads project which may also snarl up the movement of the cars in the different
lanes. Other contributors to incidents and the development of congestion within the city include
vehicular breakdowns which also impede roads (Chang and Mannering, 2009). Incidents are
expected to be any activities that contribute to the obstructions of traffic lanes, which causes a
slow movement in the traffic and thus increasing the demand of the transport road systems and
also the road capacity, to bring about traffic congestion and a slow movement in traffic. Incidents

Traffic Engineering 40
can thus be managed for the purposes of managing and avoiding congestion on the road, by
ensuring that the drivers behaviour is predicted and modelled by different tools, so that any
changes that may affect the flow of traffic may be discouraged early to ensure traffic continues to
flow even after the occurrence of an incident.
Accidents and Traffic Congestion
Accidents contribute to congestion because the accident situations have to wait for
response and emergency teams, which could take long hours to arrive, and thus the road s will
become more crowded, as the cars behind those that have been involved in an accident all have
to stall, and wait for the arrival of these response teams. This then contributes to a high level of
crowding on the roads from the stalled cars, which translates to a high demand for transport
networks as people have to wait to get the space to move and thus delays. The occurrence of
more and more accidents on the sae road could just make the congestion rates even worse,
causing a long back up of cars behind those involved in accidents (Preusser, Williams, and
Ulmer, 2015)..
Road Construction and Congestion
Road construction projects always have a negative impact on the traffic congestion rates
of a city, because they might involve the close up of a number of lanes or even the entire road,
leaving motorists who use the road to have to change the routes used, ad thus increasing the road
capacity and reducing the efficiency of the road capacity and causing delays from the slow
movement of cars on other roads and other lanes. While the use of alternative lanes and roads
allows for the movement of cars regardless of the ongoing projects, the capacity of these roads
are reduced by the increased demand and number of cars using it, leading to a slow movement of
traffic. When the rates of incoming traffic is higher than that of outgoing traffic, congestion

Traffic Engineering 41
becomes an unavoidable menace, as cars have to wait and move slowly, thus promoting
congestion (Kochelman and Kweon, 2012).
Road construction also lowers the speed limits on the roads, and the impact of this is an
increase to the rate of incoming traffic as compared to that of outgoing traffic, leading to waiting
delays and an eventual congestion on the road. Peak times on traffic are also expected to have
the highest level of delays as more cars are involved, yet the capacity is low.
Roadside building construction and congestion
Roadside building constructions could also pose construction hazards to the users of the
road around the construction site, leading to the closure of a number of lanes on the road or even
the closure of the entire road during the time the construction activities are ongoing. In addition,
the roads could also experience high traffic of construction material supply, which needs to
continue at a constant rate and is time sensitive and this could also lead to the need for closure of
some lanes for some motorists, to pave way to the construction suppliers. This is because they
utilize long and wide vehicles that move at relatively lower speeds, thus prompting congestion
within the area.
The impact of construction projects on the road could have a significant impact on the
capacity of the other lanes and roads to move traffic, as the construction related activities could
slow down movement for other motorists causing a huge delay in movement, thus a snarl-up and
the eventual impact of traffic congestion.. The congestion rates could also vary depending on the
number of motorists on the road, although the impact is felt the most during the peak hours when
the demand for traffic networks is already high (Kochelman and Kweon, 2012).

Traffic Engineering 42
As such, the management of these road occurring incidents would be an effective tool in
the management of the congestive effects, since it reduces the time taken to detect any incidents
within the road network system that may be affecting contributing to the congestion (Preusser,
Williams, and Ulmer, 2015). This enables the respective response teams for that incident to
arrive on time and help the victims to clear up the situation, allowing the rest of the traffic to
resume its operations quickest possible, and thus managing the congestion through the
management of the incident. The time taken for the road network to resume its normal
functioning capacity will thus be greatly reduced as the incident was detected and resolved in the
shortest time possible, and thus incident-resultant congestion is effectively managed and
controlled (Greibe, 2012). The incorporation of technological solution into the traditional
approaches includes the utilization of traffic surveillance systems and advanced information
communication technologies that facilitate the quick and helpful response of the responsible
response teams in the event that any form of incident occurs. This means that the incorporation
of these web and technology based solutions helps the personnel of incident management teams
to identify the kind of incident and its precise location within the road network system, allowing
for an agile and precise response for a faster resolution of incidents (Kochelman and Kweon,
2012). This also assure safety on the roads as models are used to predict the possibility of
incidents by factoring in different considerations that affect the drivers behavior. It also ensures
that the traffic rules are always abided by, to prevent and manage the occurrence of incidents.

Traffic Engineering 43
4. RESULTS
According to the information attained after modelling the SCATS of Hoodle Street, the diversion
routes that were suggested were monitored on the SCATS model. The model positively noted a
reduction in the time taken to travel on Hoodle Street after the arterial roads used as alternative
diversion routes that were used to reduce the unusual congestion from the incident modelled on
the main street. This was as a result of the SCATS using its capability as an incidence
management and traffic management tool used to prioritize the flow of traffic in various points
of the road network system to increase the efficiency of the infrastructure. This is achieved
through implementing certain alterations on the intersection points of the roads involved in this
incident, and thus balancing the capacity and efficiency of transporting people out of the
congestion to reduce congestion and return the state of the road network to normalcy. The results
from the model clearly demonstrate that the presence of an incidence increased the expected
travel time using the main street and also the demand of the diversion routes. This increase in the
demand can be attributed to the intense inefficiencies that incidents bring to the flow of traffic on
main roads, and thus to save time, the demand for the diversion routes has to be managed to
ensure that the functioning of the alternative diversion routes is optimized by ensuring that the
diversion routes are functioning within the expected capacity (Chang and Point -du-Jour, 2012).
The SCATS management tool was able to ensure the balance in the demand of the infrastructure
was managed so as to decrease the expected time of travelling to a given destination through
these diversion routes. When the action lists and variation routines are changed or altered to
balance the issues of road network demand and traffic buildup that leads to congestion, the
expected time of travel were reduced to an even smaller duration in comparison to the travel time
obtained when the SCATS tool was utilized( Cherpitel, et al., 2015). This means that making

Traffic Engineering 44
alterations to the scats tool, depending on the number of intersections and the situation on the
ground will yield more reliable solution for the management of unusual traffic which results into
serious congestion rates especially on Hoodle Street in Melbourne. Incorporating more
combinations of alterations into SCATS can thus be said to have a positive impact in reducing
the demand for diversion routes and increasing the allowable speeds, so as to keep the capacity
of the arterial roads used for diversion routes within the ability of these roads to always contain
traffic congestions. Thus the utilization of SCATS as a incident management system tool for
traffic monitoring and management was effective on roads, taking for instance the case of
Hoodle Street in Melbourne. The servers used for simulation were configured to be into the
analytical predictive modelling tool using data that has been synthesized. The users of such a
platform can benefit from specifying the duration of the simulation for any given day or for a
specific period of time, if the required data is for a set period of time. This server therefore
uploads the given matrix sets as well as the APA files of the case, so that the specific required
time period can be simulated. The achieved simulation will therefore run if the specified
simulation time. This is the reason why the specified time simulations were run on the
Mesoscopic experiment (Duncan, Khattak,. and Council, 2008). The analytic predictive
modelling tool simulation is also characterized with the functionality of validation. This
functionality enables the results of the simulated model to be compared to the results that have
been observed from the RDS.
After the multi-layered model obtained was calibrated and validated, it was time to build the
analytical predictive model. The number of patterns crated to model the typical situations of
traffic in that specific street sampling the situation of a weekday example and the two weekend
days as the reaction of the traffic is different. These three different patterns created to represent

Traffic Engineering 45
the typical scenarios of the traffic congestion on Hoodle Street on an average weekday, a
Saturday and a Sunday. The patterns then incorporated the sliced 15-minute matrices from the
macro and departure adjustment and then applied them on the tool to reflect the results of a 24-
hour period. The information obtained at this stage of the tool was used to calculate the mean
weekday traffic profile following insights from the RDS of on Tuesday-Thursday. These days
were selected out of the other weekdays because those days provide the most consistent traffic
flows using this street (Clark, 2013). This mean weekday traffic profile was used for the
purposes of explaining the reasons for the differences in the matrices and the routes used during
the entire 24 hour period. In this model, the mean weekday traffic profile was also divided into
five different intervals namely the Pre AM (midnight to 7 am), AM (7 am to 9 am), Off Peak (9
am to 16 pm), PM (16 pm to 18 pm) and Post PM (18 pm to midnight). Figure 2 below illustrates
the profile of the demand of the transport network system by road-users around the Hoodle Street
area. It utilizes the 15 minute matrices that are offered in te predictive model. In addition, the
simulated model for the mean trafic profile for Saturday utilizes three different intervals fr the
24-hour period, starting from midnight to 8 am, 8 am to 8 pm and 8 pm to midnight. This
information is demonstrated in Figure 3. On the other hand, the mean traffic profile for Sunday
utilizes three intervals for the 24-hour period, although these intervals are different from those of
on Saturday, due to the differences in the traffic patterns and expectations of incidents. The
intervals for the mean traffic profile for Sunday are from midnight to 9.00am, 9 am to 9 pm and
9 pm to midnight.
The mesoscopic and the microscopic models given in this case study ought to be consistent in the
results that they produce so that the parameters yielded by the model can be precise and accurate.
These parameters include traffic flow parameters and rates, the time taken to travel from one

Traffic Engineering 46
point to the next within the transport system, the density of the traffic, and the speeds of the
vehicles within the road at a given point. The consistency between these parameters can be
given ensuring that the results from the imported SCATS model are well calibrated and validated
so that the model being built on the ATMS has consistent outputs with the SCATS imported
model(Greene, 2010). The calibration is achieved through conducting a set of experiments using
data that has already been calibrated and validated, so that the values that are obtained and those
that are simulated by the model can be compared. In this calibration experiments, different road
topologies and considerations have to be compared and mean traffic profiles so as to ensure that
the values retrieved from the model and the known values is also precise throughout the entire
model. Some of the network topologies that are considered in these calibration experiments
include the non-urban areas, urban regions, and even mixed regions that are undergoing serious
development levels. Consistency especially within the boundaries between the mesoscopic area
and the microscopic area is of key importance because it assures that the transition between the
mesoscopic regions and the microscopic regions have continuity in the traffic conditions they
encounter (Sankaran, Gore, and Coldwell, 2015). This thus ensures that the queue formed on one
of the regions continues in a logically continuous form towards the other region.
Consistency especially in the boundary between the mesoscopic and the microscopic
regions is also of extreme importance because it ensure that the parameters based on the lanes
and vehicles do not interchange after the boundary in the model to yield mixed up results that
present as issues of aggregation and disaggregation. Other issues that could be brought about by
inconsistencies include the vehicles view inter-model and the location of boundaries between the
mesoscopic and microscopic regions(Davis, 2012). Vehicles view intermodal is brought about by
the inability of the imported SCATS model to fail to be configured to the requirements of the

Traffic Engineering 47
analytical predictive modelling tool like AIMSUN. The behavioural model of AIMSUN is able
to calculate the state of the vehicle from the SCATS model into the AIMSUN model, if it has
been calibrated and validated. The states of the vehicles considered are the position and speed of
the vehicle as modelled in the SCATS import into the AIMSUN import. Thus, the inability of the
results from the SCATS and AIMSUN model to achieve a consistency makes it impossible for
the AIMSUN model to transfer the results from SCATS and thus leads to the creation of
fictitious results showing vehicles stopped at the end of the lane. This can be avoided by
ensuring that the two regions modelled in this tool are obtained from the representation of the
entire network to allow the model to create the vehicle vie inter-model through the
representation of the internal networks (Persaud and Dzbik, 2013). The location of boundaries is
also a result of inconsistencies between the SCATS imported model and the AIMSUN model
since it is brought about by the limitations of both the regions leading to an all entrance legs in a
node that appears in that region. The gap acceptance model in AIMSUN imposes the restriction
of the models is used to decide whether or not a given vehicle can be able to cross a given
intersection in the event of an incident. The gap acceptance model in AIMSUN has a variation in
the operation between the mesoscopic region and the microscopic region due to the information
concerning vehicles that both of regions receive. For example, a mesoscopic region translates
deceleration as acceleration while the microscopic region comprehends acceleration when a
vehicle is stationary.
AIMSUN also has a lane-changing model that is based on a decision-making flowchart.
The main component of this decision tree is the ability to decide the target lane in the model for
each section of the road. This decision is made after considering many aspects including the
traffic conditions available on the roads as well as the feasible lanes that can be used to reduce

Traffic Engineering 48
the increasing demand, The traffic conditions of the available lanes are also important
considerations used by the decision tree so as to establish the best target lanes for traffic
congestion to be managed (Ison and Rye, 2013). This is because the alternative lanes are also
used to determine the maximum distance which determines the look-ahead ability of each car or
its turning movement in the plan of the path. The decision tree also considered the available
obstacles on the road such as the number of closed lanes, the reserved lanes, and the presence of
incidents that slow down the movement and flow of traffic.

Traffic Engineering 49
5. DISCUSSION
The AIMSUN software package from TSS was able to simulate the traffic activity of Hoodle
Street in Melbourne from a SCATS import model that served as the signalized arterial corridor.
This was achieved by making use of the microscale, which achieved consistency through the
calibration and validation of the results obtained from the SCATS model. The study of this case
study was able to demonstrate the impact of incidents on traffic with regard to congestion, as
incidents such as road crashes or the maintenance of roads or construction projects that affect the
utilization of a section of the road (Mayora and Rubio, 2013). An incident was defined as the any
event that would increase the demand for road network system, and thus increase the capacity at
which the traffic system is functioning at and thus promote the development of traffic
congestion. The study also demonstrated that while using an analytical predictive model like the
AIMSUN tool, Different parameters can be input into the different models of the tool to yield
different results. For instance, altering the parameters of the model that focuses on the car
following and queuing would generate a consistent rate of activity using the tool, and thus the
arterial roads on the road transport network system could achieve more improved rates of
congestion and travel time. The results clearly emulated how the model from the AIMNUS
model can be used to reduce and manage the level of traffic congestion on Hoodle Street in
Melbourne which experiences high rates of congestion due to the number of people that uses
it( Knuiman, Council, and Reinfurt, 2013). The results of the AIMSUN tool also showed that the
positions and speeds of the vehicles that were modeled represented a real case scenario of
Hoodle Street over the days and the intervals that were simulated, because these details had been
imported from the SCATS model of the region on these times and days. The mean traffic profiles
models were thus a true representation of the scenario on this road on the said times and dates

Traffic Engineering 50
meaning that the results obtained were precise and representative of the real case and thus the
recommendations drown from the model could be extremely helpful. The acceleration and speed
parameters used have also been constrained to model the real situations of the cars using this part
of the road at the said days and times, and this is why a day between Tuesday and Thursday was
picked to model the weekday used in the model as traffic in either of these days is more stable
(Knuiman, Council, and Reinfurt, 2013).
The results of the model also demonstrate that the number of obstacles like the number of stops
and the distribution of travel time along a route in the event of a traffic congestion also affect the
congestion levels and the capacity at which the roads operate in when an incident occurs. Further
the study also finds that the adjusting any of the parameters on the AIMSUN model reduces the
values of that the model produces when modelling, and thus the study decided to utilize the
default parameter of the AIMSUN software to avoid such errors. The acceleration and speed
values produced by the car following model of the AIMSUN software had a reduced simulations
and thus presents the only limitation of utilizing the AIMSUN tool for modelling for purposes of
incident management and congestion control (Karlaftis and Tarko, 2007)
. The model emitted also recommends that more experiments be conducted to establish the exact
ways in which the model can be made to achieve accurate travel time for the models created, so
that the congestion rates can be considerably managed through the optimizations done through
the predictions of the AIMSUN model. The gap acceptance, lane-changing and car-following
models of AIMSUN also ought to be incorporated into the study to achieve results that consider
all the parameters and factors that could cause incidents and how they can be managed or even
avoided. Other than these recommendations, the AIMSUN model was able to achieve insights on
how to manage incidents and the resultant congestion on Hoodle Street. The AIMSUN tool can

Traffic Engineering 51
thus be effectively used to manage incidents as has been shown in the model that was used. The
insights presented could also be used as a traffic management strategy, where the web-based
technology and ICT solutions are incorporated into traditional traffic management approaches to
achieve an effective transport network which is also environmentally friendly (Hogwood and
Gunn, 2014). This is because the AIMSUN model was able to provide incident management
insights and traffic congestion control strategies that focus on the entire road network, including
the arterial roads used mainly as alternative diversion routes in the event of an accident and the
main routes.
The effect and importance of consistency especially within the boundary between the
mesoscopic and the microscopic region of the AIMSUN model because it has a negative impact
on the dynamics of traffic within that region. The consistency within the SCATS imported model
and the AIMSUN model can be guaranteed through the selection of the right target lanes for the
incidents and the management of incident resultant congestion on Hoodle Street. The selection of
the target lanes also has to be done considering the look-ahead ability that the vehicles have for
an efficient management of traffic. The lack of consistency also affects the model’s ability to
provide reliable insights because the vehicles on the specific section of the road, in this case
Hoodle Street, will fail to anticipate the traffic conditions experienced on the downstream side of
the flow of traffic(Mensah and Hauer, 2008). The importance of consistency is also clearly
brought out in the results of the model which show discrepancies in the special features of the
roads such as the bridges, round abouts and even tunnels. This common error can be reduced by
increasing the look-ahead of the cars in the model, so as to improve the results of both the
mesoscopic and the microscopic area in the model built on AIMSUN.

Traffic Engineering 52

Traffic Engineering 53
6. CONCLUSION
The menace of traffic congestions within major cities in Australia continues to increase and
present serious impact on the economy of the different cities in the country as well as the
commuter public. The level of congestion that has this kind of impact on the country and its
major urban centers is mainly as a result of incidents which impair the capacity of these transport
networks to ferry people between different destinations. The resultant congestion leads to a great
variation in the expected and actual time that is taken to travel from one destination to the next as
a result of serious delays that have been recorded in many parts. This is because the incidents
affect the capacity of the roads to function efficiently to ferry people from different destinations,
thus affecting the efficiency of ferrying and the operational capacity of the road network. This
study was able to provide an analysis of the use of technology based solutions and traditional
approaches of traffic management incorporated together to yield strategic and effective incident
management approaches that can also be implemented to resolve traffic resulting from road
incidents (Miaou, 2014). It has also highlighted how the SCATS and AIMSUN tools have been
used to model the traffic of Hoodle street during incidences so as to obtain insights on how to
manage these incidents and the resultant traffic congestion.
Managing the incidents that occur on such roads would greatly improve the congestion
rates in different streets and roads on the road transport network. This can be achieved by the
implementation of strategies and systems for incident management which could be effective in
mitigating the congestion that results from road incidents like road crashes, maintenance or
repair works on the roads as well as other events that would lead to a go-slow in the roads
(Navon, 2012). Congestion brought about by incidents occurring on the road to slow down the
movement of traffic on the roads is known as unusual congestion. The use of adaptive signal

Traffic Engineering 54
control tools like SCATS could be an effective means to mitigate the occurrence and the
intensity of congestion in the street through managing incidents that cause this unusual
congestion. As a strategy for the management of incidents on the roads, SCATS will require the
additional feature of the tool to be altered and configured to provide a more focused approach to
improve the capacity of the roads after an incident and thus contain the level of congestion.
However, the SCATS tool could be effective in the reduction of congestion to a more reasonable
level through adapting the signal control in traffic systems in the real time to alter and balance
the demand (Koorey, McMillan, Nicholson, 2008).
.
.

Traffic Engineering 55
7. FUTURE WORK
This study was able to provide an analysis of the use of technology based solutions and
traditional approaches of traffic management incorporated together to yield strategic and
effective incident management approaches that can also be implemented to resolve traffic
resulting from road incidents. Further research can be conducted regarding how incident
management systems can be used for the management of incident based traffic congestion. This
research should also look into the different factors that contribute to the occurrences of incidents
on Hoodle Street and their frequency of occurrences, so that the same factors can be used to
build a more predictive model to analyze how incidents on Hoodle Street can be managed and
avoided so as to avoid the congestive impact of these incidences. The benefits of incidence
management on Hoodle Street could also be studied further, so as to encourage all the
stakeholders of that specific road, including the general public and the related government
agencies to jump on board to adopt an incidence management system to manage the common
congestion problem experienced by the road users are caught up in it (O’Donnell and Connor,
2006). The traffic causes serious delays on the road network system and thus its management
through incident management would be extremely important.
Further, other studies should also be conducted on other traffic management and traffic
incident modelling tools to be utilized to manage incidents on Hoodle Street so as to establish the
best or the most effective tool for this specific road within the Melbourne road transport network
system. Other recommendations for future works within this line of work includes the
relationships between the occurrence of incidents on the movements to change lanes or reduce
the gaps between the cars so as to incorporate these parameters in the AIMSUN models for the
predictive modelling and incident management insights for the sake of traffic congestion. The

Traffic Engineering 56
contribution of the geometry of the road to the occurrence of incidents, as well as the common
behaviors of road accident prone drivers can also be analyzed do that the parameters of these
considerations can be factored on this AIMSUN model of an incident management system on
Hoodle Street. Other types of incidents that are noted on Hoodle Street and their frequency so
they can also be included in the considerations of the technology based incident management
system used for congestion control. The effects of the incident rate while the responding and
management of other incidents and its impact on congestion especially on Hoodle Street (Zhou
and Sisiopiku, 2007). It would also be important to study the capacity of the other arterial routes
surrounding Hoodle Street which would be used as alternative diversion routes of the road
network system.

Traffic Engineering 57
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