As a graduate civil engineer, you have been appointed as the lead consultant to advise on traffic and transportation issues relating to proposals for the building of a new city in Southeast Asia. The site is located off a major highway single 2-lane on the site of a former coal mining quary. Specifically, you are required to
- Provide pavement design solutions for the major highway to accommodate the anticipated traffic generated as a result of the new oil field development
- Advice on the impact of overloading which is an endemic problem in the country.
- Assess the safety of local residents through the provision of adequate pedestrian crossings and
- Discuss contemporary sustainability issues related to transportation that your client should be aware of.
Relevant portions of the Design Manual for Roads and Bridges should be used to be consulted.
Further additional information and requirements for the new development that could assist you in your assessment are shown below.
- Pavement design
Using the traffic data in Table Q1.1, design a conventional flexible pavement indicating the thicknesses of the various layers including the granular subbase and the bituminous bound upper layers. For the pavement, the foundation assumes a subgrade CBR of 6. Subbase materials are to be unbound materials only. Because of the weak subgrade, the foundation must include a capping layer. Provide a neat, well-labeled sketch of the resulting design. Your designs must clearly show:
- Design traffic in msa
- Pavement foundation including a capping layer
- Aphalt surfacing for conventional commercial vehicles
- Aphalt surfacing for assuming that all OGV2 vehicles have the loading configuration shown in Figure Q1.1. Justify your approach using the principle of load-equivalency to support your answer
Assume a flexible pavement and a design life of 40 years.
Table Q1.1. Traffic data (2-way)
|Light Goods Vehicles (LGV)||1,899|
|Buses / Coaches (PVS)||56|
Figure Q1.1. Axle configuration for assumed OGV2 vehicles in Q1d
- Traffic analysis for junction design
The highway is due to open on the first day of 2029. On 1 March 2019, the traffic flow on the highway was measured at an equivalent Annual Average Daily Traffic (AADT) of 19,363. Assuming that the vehicular traffic is composed of the five classes (cars, PSV, LGV, OGV1, and OGV2) as shown in Table Q1.1, calculate the AADT for the opening year using the DfT high- and low-growth estimates. On the basis of the forecasted AADF range in the opening year, determine the appropriate junction layout. It is estimated that the flow on the access road to the estate will be less than 1,000 vehicles AADT 2-way. Provide a brief description and a neat layout of the junction.
- Traffic analysis for pedestrian safety (10%)
Approximately 50% of personal injury accidents in Great Britain occurred at urban road junctions. With this background, assess the need for a controlled pedestrian crossing facility on the highway if the hourly traffic shown in Table Q3.1 is anticipated as a result of the new estate development. Discuss two limitations of the approach used.
Table Q3.1. Vehicular and pedestrian traffic data (7:00 am – 7:00 pm)
P = number of pedestrians measured with 100 m of the crossing; V = number of vehicles
- Highway Legislation
There are many benefits related to the UK transportation system, but there are also many costs or detrimental effects that have come into focus in recent years. Briefly discuss three major detrimental effects that are directly related to the construction and use of our transportation system. Give two examples of UK government policies/schemes that attempt to address the detrimental effects of transportation on society.
Top marks to be awarded to well-presented submission satisfying all submission requirements.