Highway design | Civil Engineering homework help

1. How much capacity is needed to withstand 5 million ESALS with 95% reliability, a standard deviation of 0.35, a tolerable loss in serviceability of 1.9 units, and an Mr for subgrade design of 5,000 psi.

A) Solve using equation 11.37 B) Solve using nomograph

2. Re-arrange eqn 11.37 by subtracting log (W18) from both sides of the equation. Use the given information from part 1) and plot the residual on the y-axis versus SN on the x- axis. Comment on the results in one paragraph. This problem should be performed in an excel spreadsheet. Basically, set eqn 11.37 equal to zero and input several SN values (only one value will equal zero while all others will be non-zero-these are residuals).

3. Consider the pavement in problem 1 as the base condition and perform a sensitivity analysis that considers Mr and ESALS. Use 1000, 8000, and 12000 as Mr values and use 1, 10, and 20 million ESALS. Which of these variables has more influence on the structural pavement capacity needed? Provide discussion to justify your answer.

4. A new pavement is to be designed with 90% reliability, a standard deviation of 0.35, and a tolerable loss in serviceability of 1.9 units. It is known the traffic will not exceed 5 million ESALS and the resilient modulus will not exceed 5,000 psi. Perform a sensitivity analysis of this condition in terms of Mr and ESALS. Use 1500, 3000, and 5000 as Mr values and 0.5, 2.5, and 5 million ESALS. Is the result the same as problem 3? Justify your answer.

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