Civil Engineering PE Prep 3

Question 1

A 10-ft diameter circular pipe flows half-full. The hydraulic radius is:

Accepted Answer

2.5 ft

Answer

For a circular pipe at half-full, R = D/4 = 10/4 = 2.5 ft.

Question 2

Which AASHTO soil classification group generally represents the best subgrade material?

Accepted Answer

A-1-a

Answer

A-1-a represents well-graded gravel and sand with excellent subgrade performance (GI = 0).

Question 3

The critical path in a CPM schedule is defined as the sequence of activities that:

Accepted Answer

Has zero total float and determines project duration

Answer

The critical path consists of activities with zero total float; any delay extends the project end date.

Question 4

A steel column with an effective length KL = 15 ft and radius of gyration r = 2 in has a slenderness ratio of:

Accepted Answer

90

Answer

KL/r = (15×12)/2 = 180/2 = 90.

Question 5

In stormwater design, the Rational Method formula Q = CiA requires the rainfall intensity (i) to be evaluated at:

Accepted Answer

The time of concentration of the watershed

Answer

i is selected from IDF curves at the storm frequency and duration equal to the time of concentration.

Civil Engineering PE Practice Test