VERTICAL ALIGNMENT AND SUPERELEVATION
Objective: This assignment develops students' ability to design the vertical profile and cross sections for a given road alignment.
Students will work in pairs on this assignment but not with a student with whom you have worked on a previous assignment in this subject.
A 400m length of mountain road is being designed from point A as shown on the attached plan at scale 1:2500 (CH 300.00) through the TS at CH 340.00 and ST CH 380.00 through a 150m radius arc to a CS and ST (40m spiral) to the final (for the assignment) point C (not shown) at CH 700.00.
At point A the road bearing is 112.92°, RL is 37.00 with an existing grade of -2.8%. At point C the road bearing is 360.00° and RL of the road is to be 38.00 with a grade yet to be determined.
1. Calculate the chainage of the CS and ST and design the vertical alignment of the road for a design speed of 70km/h. Draw an appropriate longitudinal section showing lengths of all vertical curves and tabulate CL levels at 20m chainages from CH300.00 to CH700.00.
2. Design the superelevation development and draw the edge profiles on a centreline profile
3. Determine and tabulate the cross section levels of points 1, 3 and 5 (shown below) at 20m intervals from CH300.00 to CH400.00. Note that the road has sealed shoulders
4. Determine the earthwork quantities at 20m intervals over the length of the road. (Pavement depth can be neglected. Fill batters 3:1, Cut batters 1:1 plus appropriate drain). Tabulate your calculations and results.
5. The earthworks must be completed in 2 weeks and the equipment items available are: Excavators with bucket capacity 1.2m3
Scrapers with carry capacity 10m3
Dump trucks with capacity 12m3
Determine the number of each item of equipment required to complete the earthworks in 2 weeks. Note all your assumptions made in your calculations.
Attachment:- MAPA.rar