Civil Engineering Technology Assignment

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Civil Engineering Technology1CIVIL ENGINEERING TECHNOLOGYNameCourseProfessorUniversityCity/stateDate
Civil Engineering Technology2Table of Contents1.Task 1: Earthmoving equipment, safety in deep excavation and temporary works.....................31.1.Task 1.1: Earthmoving equipment...........................................................................................31.1.1.Use of earthmoving equipment.............................................................................................31.1.2.Categories of excavation and earthmoving equipment and their uses...........................41.2.Task 1.2: Techniques used to ensure safety and productivity during deep excavations.......51.2.1.Protective systems................................................................................................................51.2.2.Personal protective equipment.............................................................................................61.2.3.Qualified personnel..............................................................................................................61.2.4.Underground utilities...........................................................................................................61.2.5.Safe access and egress.........................................................................................................61.2.6.Appropriate equipment........................................................................................................61.2.7.Environmental events...........................................................................................................61.2.8.Dangerous atmosphere........................................................................................................61.2.9.Nearby buildings..................................................................................................................71.2.10.Other tips.............................................................................................................................71.3.Task 1.3: Temporary works required in ground stability and groundwater works.............71.3.1.Dewatering...........................................................................................................................71.3.2.Ground freezing...................................................................................................................81.3.3.Shoring................................................................................................................................92.Task 2: Pile installation, complex foundation construction and underground constructionmethods......................................................................................................................................................92.1.Task 2.1: Techniques used to install piling systems................................................................92.1.1.Types of piles.......................................................................................................................92.1.2.Techniques of pile installation.............................................................................................92.1.3.Soil stabilization methods..................................................................................................122.2.Task 2.2: Method of constructing complex foundations.......................................................122.2.1.Trenching methods............................................................................................................152.2.2.Trenchless construction methods.......................................................................................163.Task 3: Construction methods, and falsework and formwork.....................................................173.1.Task 3.1: Appropriate construction methods........................................................................173.1.1.Substructure.......................................................................................................................173.1.2.Superstructure units...........................................................................................................173.1.3.Lightweight cladding structures.........................................................................................18
Civil Engineering Technology33.2.Task 3.2: Use of falsework and formwork in reinforced concrete structures.....................183.2.1.Uses of formwork and falsework.......................................................................................183.2.2.Types of formwork............................................................................................................194.Task 4: construction hazards, health and safety legal framework, and planning supervisor....194.1.Task 4.1: Hazards from civil engineering activities..............................................................194.2.Task 4.2: Legal framework of health, safety and welfare and requirements of construction(design and management) (CDM) 2007..............................................................................................214.2.1.Duty holders and roles.......................................................................................................214.2.2.Factories and industrial undertaking ordinance (Cap 59) Hong Kong regulations.............224.3.Task 4.3: Role of planning supervisor in civil engineering activities...................................225.Task 5: Civil engineers in problem solving....................................................................................235.1.Task 5.1: Solutions to civil engineering..................................................................................235.1.1.Modern technology............................................................................................................235.1.2.Green building concept......................................................................................................245.1.3.Quality control...................................................................................................................245.1.4.Safety measures.................................................................................................................245.1.5.Renewable energy..............................................................................................................245.1.6.Recycling...........................................................................................................................245.1.7.Waste minimization...........................................................................................................245.1.8.Alternative materials and production methods...................................................................245.2.Task 5.2: Safety plans for problems arising from civil engineering activities.....................255.2.1.Roles and responsibilities...................................................................................................255.2.2.Safety procedure................................................................................................................255.2.3.Emergency procedure........................................................................................................26References................................................................................................................................................26
Civil Engineering Technology41.Task 1: Earthmoving equipment, safety in deep excavation and temporary works1.1.Task 1.1: Earthmoving equipment1.1.1.Use of earthmoving equipmentEarthmoving equipment are generally used for digging, lifting and moving earth or wasteloads generated on construction sites. Therefore earthmoving equipment comprises of equipmentused to excavate earth, lift and load it, and move it from one place to another.1.1.2.Categories of excavation and earthmoving equipment and their usesBelow are the four main categories of excavation and earthmoving equipment and their uses:Excavation: this category comprises of machines used for digging/excavating, trenching ormoving large objects. They are commonly known as excavators and are used in both small andlarge scale construction projects. An excavator can either be wheeled or tacked. Both of them arevery versatile but tracked excavators have greater traction and floatation characteristics[ CITATIONHea17 \l 1033 ].The several uses of excavation equipment are: site preparation; diggingfoundations, holes and trenches; material handling; demolition; lifting and laying pipes;installation of underground utility; general landscaping and grading; etc. Common machinesunder this category include: excavator, bulldozer, trencher and backhoe loader. In this context,excavation equipment are construction machines that are only used for digging or excavatingearth. Below is an example of an excavation equipment.Excavation and load: this category comprises of machines that are used to excavate rocks andearth and load them onto another truck for dumping. These equipment excavate earth then scoopup the excavated materials (soil, rocks, etc.) from the ground and load them onto a dump truck.Examples of excavation and load equipment are wheel loader (also known as bucket loader, skiploader or front loader), excavator, backhoe loader, crawl loader, skid loader, poclain/JCB,loading shovel and bulldozer (crawler)[ CITATION Sur14 \l 1033 ].Below is an example of anexcavation and load equipment.
Civil Engineering Technology5Haul and deposit: these are equipment used for moving excavated materials from theexcavation point to fill area. They can also be used for moving other items besides excavatedmaterials. Common examples of haul and deposit equipment are dump trucks (known asdumpers), scrapers, tippers, poclain/JCB, trailers, tractors, cranes, bulldozers, excavators, loadersand shovels[ CITATION Ric16 \l 1033 ].Scrapers are suitable for use in large construction sites withadequate open space[ CITATION Rod17 \l 1033 ].Below are examples of haul and depositequipment.Excavation, load, haul and deposit: these are equipment that can be used to excavate or digearth, load loose materials onto hauling machines, transport the excavated materials and depositthem in fill areas. Examples of these equipment are: excavators, bulldozers, backhoe loaders,crawler loaders, loading shovel, forward loader, JCB, etc. These equipment have variedcapacities for each of these operations (excavation, loading, hauling and depositing). Some ofthem have greater capacity to excavate and load than haul and deposit, and vice versa.Excavation, load, haul and deposit equipment are usually not designed to haul materials overlong distances and therefore after excavating materials, they can only move them within the siteand not to fill areas located several miles away. Below are some of the excavation, load, haul anddeposit equipment.
Civil Engineering Technology61.2.Task 1.2: Techniques used to ensure safety and productivity during deepexcavationsThere are several safety issues that cause hazards and risks when undertaking deepexcavation activities. Some of the safety issues include: working in confined space, working atheight, collapse of excavated sides (cave-ins), flooding due to water ingress, destruction ofunderground utilities causing explosion or electrocution, falling loads, falls, moving equipment,etc. Therefore there is need to ensure that appropriate measures are put in place so as to preventor mitigate these hazards and risks. Some of these techniques are as follows:1.2.1.Protective systemsAppropriate protective systems should be put in place to ensure safety of workers performingexcavation and trenching activities. These systems include sloping, benching, shoring andshielding. Sloping entails cutting out sides of the trench at an angle from the excavation.Benching involves cutting steps into the trench sides. Shoring involves installation of differenttypes of supports, such as aluminium hydraulic systems, on the sides/walls of trench or holeexcavated to prevent cave-ins or soil movements. Shielding involves use of support systems,such as trench shields or trench boxes, to protect workers by preventing soil cave-ins[ CITATIONSaf13 \l 1033 ].1.2.2.Personal protective equipmentAll workers must be in appropriate personal protective equipment (PPE) before enteringexcavation trenches. Depending on the type, depth and conditions of excavation, some of thePPE may include gloves, apron, safety eyewear, hearing protectors, hard hats, high-visibilityvests or reflector jackets, safety footwear (such as steel toed boots or shoes), etc. The specificPPE to be worn may also depend on the specific type of excavation work being carried out.Workers entering deep excavations should also have a harness attached with a lifeline[ CITATIONCen172 \l 1033 ]. The supervisor should ensure that PPE are inspected regularly for signs ofdamage or wear and tear.1.2.3.Qualified personnelAll excavation and trenching activities should be carried out by trained and qualifiedpersonnel. Machine operators should be well-trained and experienced to ensure efficient and safeoperations. Competent persons should also inspect trenches daily before allowing entry ofworkers to ensure that potential excavation hazards are eliminated. Inspection should also bedone throughout the deep excavation process. The company should also provide training to itsworkers frequently to ensure that they have proper, adequate and updated knowledge on latestsafety measures.1.2.4.Underground utilitiesIt is important to identify and mark location of all underground utilities present on site beforecommencement of any excavation work. Doing so will prevent numerous dangers, damages,losses and inconveniences. For example, if a water main is cut then the excavation may collapsequickly causing risks to the lives of workers and losses to the company.1.2.5.Safe access and egressAll deep excavations should have safe access and egress to enable easy entry and exit ofworkers. The access and egress facilities include steps, ladders, ramps, etc. These facilitiesshould be provided for all excavations that are 1.22 m or deeper and must be positioned within7.6m of all workers[ CITATION Occnd \l 1033 ].
Civil Engineering Technology71.2.6.Appropriate equipmentDeep excavation should also be done using suitable types of equipment. These equipmentshould be approved and used by following the manufacturer’s manual. They should be integratedto ensure flawless excavation, loading, hauling and deposit of loose materials. The equipmentshould be maintained and cleaned properly to ensure operational safety and efficiency. Mostimportantly is that the equipment must be operated by qualified personnel.1.2.7.Environmental eventsIt is also important to identify and assess environmental events and their related hazards.Such events include rainstorms, which can cause instability of walls, or absorption of excesswater resulting to a slide[ CITATION Mee14 \l 1033 ].Other events that should be analyzed includesandstorms and earthquakes. If any of these events occur, trenches must be inspected beforeallowing workers to progress.1.2.8.Dangerous atmosphereFactors that can cause hazardous atmosphere include excavating near a sewer, toxic site orlandfill, or using chemicals near or inside the excavation or trench. Some of the majorcontributors to dangerous atmospheres are: presence of highly flammable or toxic gases, andoxygen deficiency. Suggested strategies to overcome their impacts include: using appropriatePPE and installing ventilation systems to supply adequate fresh air[ CITATION Uni172 \l 1033 ].1.2.9.Nearby buildingsDeep excavations may affect stability of nearby structures, such as buildings. For this reason,it is important to assess the possibility of the excavation affecting stability of nearby structuresand establishing the need to install bracing supports or other systems. These protection systemsshould ensure that the excavation does not affect nearby structures adversely[ CITATION Wor172 \l1033 ].1.2.10.Other tipsOther tips that improve safety during deep excavations and trenching include: securing workarea; managing traffic; storing excavated spoil or plant away from the excavation sides toprevent them from falling into the excavated hole; installing barriers around theexcavation[ CITATION AiS17 \l 1033 ];not working under raised or suspended loads excavation orloading equipment[ CITATION Occ15 \l 1033 ];checking & complying with local safety and healthrequirements related to excavation works[ CITATION Ont15 \l 1033 ]; fixing safety signs atdesignated places; and frequently reminding workers about safety and health regulations andtips[ CITATION Nor17 \l 1033 ].1.3.Task 1.3: Temporary works required in ground stability and groundwaterworksControlling groundwater and ensuring ground stability during excavation are very important.These are several temporary techniques that can be used to control groundwater and groundstability during excavation. The following are some of this techniques:1.3.1.DewateringThis is one of the major methods used for controlling groundwater temporarily. There areseveral dewatering methods used in construction industry. The two main methods are: exclusionmethod and pumping method.
Civil Engineering Technology8Exclusion method: this method involves installing an impermeable structure (known as cut-off wall) to prevent groundwater from the excavation. The cut-off wall stops flow ofgroundwater to the excavation. Cut-off walls can be created using various geotechnical methodsincluding: slurry trenches and walls, steel sheet piles, compressed air, freeze walls, secant pilewalls, diaphragm walls, grout curtains, etc. If properly installed, cut-off walls eliminate or reducethe need for pumping groundwater[ CITATION Gro14 \l 1033 ].Some of the methods used toconstruct or install cut-off walls are: underground excavation and caissons. Undergroundexcavation is used when it is not desirable or possible to lower the level of groundwater or wherethe soil is extremely pervious. Caisson is where a caisson structure is constructed and duringexcavation, the structure is sunk by imposed loads or self-weight. Instead of installing a cut-offwall, the excavation can also be protected against groundwater by diverting the water.Pumping method: this method entails pumping groundwater from several sumps or wells soas to lower groundwater levels temporarily and allow excavation works to be undertaken understable and dry conditions. Figure 1 below is a schematic diagram of a groundwater pumpingsystem.Figure 1: Schematic diagram of groundwater pumping system[ CITATION Pre14 \l 1033 ]There are 5 common pumping techniques used for groundwater dewatering: sumppumping system, well point system, deep well system, ejector or eductor system and siphondraining system. Sump pumping system is where groundwater is allowed to flow into theexcavation and collected in sumps from where the water is pumped out[ CITATION WJG17 \l 1033 ].Well point system is where rings or lines of closely well points (shallow wells) are set up aroundthe excavation and connected to a header pipe. Well point pumps are then used to pump waterfrom these shallow wells on the principle of suction. Deep well system is where electricsubmersible pumps are used to pump groundwater from a bored well. The wells are bored roundthe excavation perimeter. Ejector well system is most suitable regulating pore water pressuresfound in materials that are less permeable. The system’s operation is based on venturi principle.Here, a vacuum is created as high pressure water circulates in the ejector wells. This vacuumfacilitates drainage in strata with low permeability. Siphon draining is where water is pumpedfrom installed wells by gravity through siphon pipes. The wells have to be installed above theexcavation’s unstable zone so that the pumping can be enabled by gravity[ CITATION Mov16 \l1033 ].
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