Marshall Method of Mix Design | Geometric Design

Added on -2020-02-05

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Technical report, calculations and drawings required for the design of a highway project. Submitted to:Prepared by:1| P a g eDEPARTMENT OF TRANSPORTATIONENGINEERINGDEPARTMENT OF TRANSPORTATIONENGINEERINGHIGHWAY ENGINEERINGHIGHWAY ENGINEERING
Table of Contents1.Design of Highway Project....................................................................................31.1. parameters.................................................................................31.1.1. design speed..............................................................................31.1.2. site distance requirements............................................................31.1.3. stopping sight distance.................................................................3 1.1.4. overtaking sight distance ............................................................31.1.5. degree of curve.........................................................................31.2. horizontal alignment & vertical alignment design................................41.2.1. gradient....................................................................................41.2.3. cross section elements..................................................................51.2.4. carriage way width.....................................................................51.2.5. shoulders.................................................................................51.2.7. side slopes................................................................................51.2.8. cambers...................................................................................51.2.9. safety fences.............................................................................62.4. bitumineous mixes design ..............................................................112.4.1. objectives of mix design..............................................................112.5. marshall methods of mix design......................................................122.5.1. calculations.............................................................................123. results.........................................................................................194. References...........................................................................202| P a g e
1.Design of Highway Project:The geometric design of a vehicle and route planning on the rate with the needs of the driver. Are taken into account in the design of road engineering Key features horizontal and vertical curvature of the cross section of the road is clear and features. Geometric design makes good driverscar exercises to ensure that appropriate levels of safety and comfort for the design speed, according to the design of roads and harmony of nature and Finance.1.1. Parameters:1.1.1.Design speed:The design of the road section is an important factor for the design speed. It's just thedisplay of the radio and distance, Super development and transfer of methods to determine theaverage speed as a guide by the designers.1.1.2.Sight distance requirements:Sight distance- the length of carriageway visible to a driver in both the horizontal and vertical planes- is the most important feature in the safe and efficient operation of a highway.1.1.3.Stopping sight distance:Heights and accessories eyes, branches to ensure a clear view of the existence of an envelope that allows you to search for used cars, many of the road and reduce high utility vehicles and other vehicle drivers use the tree can be spread on the road. The lower and upper eye heightsused in Britain are 1.05 m and 2 m respectively.Stopping sight distance = stopping time (d1) + braking time (d2)1.1.4.Overtaking sight distance1)Vehicle that is passed travels at uniform speed.2)Speed of passing vehicle is reduced behind passed vehicle as it reaches passing section3)Time elapses as driver reaches decision to pass4)velocity of the passing vehicle is 10 mph greater than that of the passed vehicle1.1.5.Degree of curve it is a measure of the sharpness of curve and is frequently used instead of the radius in the actual construction of horizontal curve. The degree of curve is directly related to the radius of the horizontal curve byRD6.57291.2.Horizontal alignment design and Vertical alignment:1)Along circular path, vehicle undergoes centripetal acceleration towards center of curvature (lateral acceleration).2)Balanced by superelevation and weight of vehicle (friction between tire and roadway).3)Design based on appropriate relationship between design speed and curvature and their relationship with side friction and super elevation. 3| P a g e
Vertical alignment specifies the elevation of points along roadway. The elevation of these roadway points are usually determined by the need to provide an acceptable level of driver safety, driver comfort, cut to fill and proper drainage. Each roadway is uniquely defined by stationing (which is measured along a horizontal plane) and elevation.1.3.Design or crest and Sag curve:G1:is the initial tangent grade or initial roadway grade from left to right, G2:is the final roadway (tangent) grade, A:is the absolute value of the difference in grades (initial minus final expressed in %), L: is curve length (m)T:is the initial point of the curve (PVC)P: (PVI) is the point of vertical intersection (intersection of initial and final grades), andT1: (PVT) is the point of vertical tangent, which is the final point of the vertical curve (i.e., thepoint where the curve returns to the final grade or, equivalent, the final tangent).1.3.1.Gradient:Although the use of shadows sharp gradients in mountainous terrain usually results in lessroad construction and environmental costs as it adds to the cost of road users by delays andadditional fuel and accidents. Additional operating costs are more visible when heavy traffic andtraffic of commercial vehicles are an important part of the traffic flow.4| P a g eTG1G22L2LPT1θTG1G22L2LPT1θCrest Vertical CurvesSag Vertical Curves
1.3.2.Climbing lanes Maximum slope is not in itself an element of a comprehensive design control and often offeradditional track to climb long hills climbing. It is a climbing route add-on is usually when thecombination of the severity of the hill, and the volume of traffic and the configuration is such thatthe operational benefits that have been achieved are greater than the additional cost of pro Vidingadditional lane.1.3.3.Cross-section elements By section elements and objectives of these features that are the width of the effective way.There are two types of elements, primary and secondary. The main basic features is the view oftransport vehicles (including the number of channels), central reservation (or average) and theshoulder area (including the point), laybys, the curvature of the road, and other slopes of cuttingsand embankments1.3.4.Carriageway width More traffic volume increases on a larger scale on the track and in general, increasing the number of lanes. wide sidewalks heavier commercial vehicles should ensure relevant when approvals. Vehicles traveling at high speed, in particular commercial vehicles, which requires a widerroads to ensure safety approvals between passing cars road classification.Shoulders The shoulder is clear in the context of a cross section adjacent to the edge of the runway track.Shoulders serve a number of objectives haven for forced to stop in an emergency cars, and therecovery area of vehicles leaving the road intentionally or not do during an emergency evasivemaneuver.1.3.5.Laybys and bus bays Must provide Laybys Instead, the separation must be adapted to the volume of traffic. It is 2.5meters and to provide screen 2.5 m and 3 m wide by 30 m long laybys at 1.5 km and 5.8 kmintervals, respectively, on either side of the carriageway, while 3 m wide by 100 m long laybys areprovided at approximately 1 km intervals on each side of dual carriageways.1.3.6.Side-slopes Analysis of soil mechanics can accurately determine the maximum slopes of earth dams or cuts can safely withstand. However, these ends are not always used, especially in bridges which are not protected by walls.1.3.7.Camber Camber Hump used to describe the curvature of the cross-section of the plant. Your goal is toclear the road surface water and prevent deformation of the surface of the seal on the road.1.3.8.Safety fences Roadside safety fences a longitudinal protection system aimed at reducing the severity resulting from vehicles leaving the road accidents. It can be divided into two main groups: the edge of the barriers and fences. The edge of the barriers tends to be used along the roads and bridges with the side slopes of a steep ditch impassable.5| P a g e
Fig. Cross-section of highway.6| P a g e

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