NG2S102 - Engineering Surveying & Highway Design - University of South Wales

Assessment Title - Integrated Highway Design Project (IHDP)

Learning Outcomes

LO2. (BSc) Demonstrate awareness of the political, commercial, economic and planning background applicable to the formulation of highway schemes, and to make design alternatives and carry out comprehensive designs evaluations for sustainable highway and traffic schemes, based on sound knowledge of engineering principals and analytical skills.

LO4. (BEng) Demonstrate understanding and ability to solve highway and traffic engineering problems for different socio-economic conditions based on professional designs, conduct and codes of practice, so as to make critical design alternatives and carry out comprehensive designs evaluations for sustainable highway and traffic schemes, based on sound knowledge of engineering principals and analytical skills.

Integrated Highway Design Project (IHDP)

1. Summary

There is a proposal to construct a two lane single carriageway road to connect the village of Llanharan to the M4 Motorway at a point between the villages of Llanharry and Brynsadler.

The project details are as follows:

Design life (n) - 15 years
Rate of growth of commercial vehicles (r) - 2.5% Composition of Heavy Goods Vehicles - 22% of AADT AADT at year of opening the road - 3,000 vpd

AADT at year of the end of design life is expected to be at 8,000 vpd (i,e. an extra 5,000 vpd will have been generated traffic). Assume uniform traffic generation throughout the design life

2. Design Part 1 - Horizontal and Vertical Alignment Contribution

Coursework detail

Aims
a) To be able to identify and compare route corridors and to reasonably avoid major obstacles in a proposed route.
b) To be able to interpret the effect of varying the different traffic parameters on the design properties of a section of highway.
c) To be able to identify and determine the parameters necessary for the design of both horizontal and vertical alignments
d) To be able to design both horizontal and vertical alignments of a section of highway.

Tasks

Using the area map provided, design and present drawings, showing:

1. The horizontal alignment of the road
Key milestones:
• Use speed distribution above to obtain 85th percentile speed, and hence establish Design Speed for the road;
• Using map provided, establish a realistic route corridor in straight lines;
• Co-ordinates of all key points on the route corridor;
• Bearings of all straights;
• Intersection angles at IPs;
• TP-IP distances;
• Any other activity relevant to horizontal alignment design.

(You any use the MS Excel programme provided for horizontal alignment design, for all or any of these steps. When this programme is used, you are required to show one sample calculation for each step).

2. Vertical alignments of the road
Key milestones:
• Using contours, a plot of existing ground profile along the route;
• Approximate finished road profile in straight lines, relative to the existing ground profile;
• Determination of slopes of these straight lines;
• Design of vertical curves using the slopes;
• Indication of possible locations for: drainage structures (excluding their exact design details); materials bore holes/trial pits; scales (horizontal and vertical), any other details
• Any other activity relevant to vertical alignment design.

3. Design Part 2 - Pavement and Drainage Design Coursework detail Aims

a) To be able to identify, interpret and determine the parameters necessary for carrying out a practical and realistic traffic forecast, for both total and commercial traffic.

b) To be able to identify, select and compare different materials for pavement design

c) To be able to interpret the behaviour of a pavement in relation to the different pavement layers and to the different materials used in the construction of the pavement.

d) To be able to identify, understand and establish the parameters necessary for carrying out a detailed highway drainage system, including the establishment of surface run-off from available hydrological and meteorological data.

Provide designs and drawings, showing calculations and details of the road pavement and drainage considerations that you have taken into account .

A. Pavement design for the road, assuming generated traffic value of 5,000 vpd

Key milestones
• A traffic forecasts for total traffic at the time of opening the road;
• A traffic forecasts/estimate for total commercial traffic at the time of opening the road;
• A traffic forecasts for total commercial traffic at the middle of the 15-year design period for the road;
• Road Damage Factor at the middle of the 15-year design period for the road;
• Cumulative Standard Axles at the end of the 15-year design period for the road;
• Using charts, thicknesses of the various pavement layers.
• Final drawing(s) of the pavement layout, including material types and thicknesses for each pavement layer.