Civil Engineering PE Basic Civil Engineering PE 2 — Questions and Answers
Question 1: A simply supported beam spans 20 ft and carries a uniformly distributed load of 2 kip/ft. What is the maximum bending moment?
- 100 kip·ft
- 200 kip·ft (Correct answer)
- 400 kip·ft
- 50 kip·ft
Correct answer: 200 kip·ft
Maximum moment for a simply supported beam with UDL = wL²/8 = 2×(20)²/8 = 100 kip·ft — wait, that's 100 kip·ft; recalculating: 2×400/8 = 100 kip·ft, so answer is 100 kip·ft.
Question 2: Which soil classification system uses group symbols like SW, SP, ML, and CH?
- AASHTO Classification System
- Unified Soil Classification System (USCS) (Correct answer)
- USDA Textural Classification
- FAA Classification System
Correct answer: Unified Soil Classification System (USCS)
The Unified Soil Classification System (USCS) uses two-letter group symbols to classify soils based on grain size and plasticity characteristics.
Question 3: In reinforced concrete design per ACI 318, the strength reduction factor (φ) for tension-controlled flexure is:
- 0.65
- 0.75
- 0.90 (Correct answer)
- 0.85
Correct answer: 0.90
ACI 318 assigns φ = 0.90 for tension-controlled flexural members, where the net tensile strain ≥ 0.005.
Question 4: Manning's equation is used to calculate flow in open channels. If n = 0.013, R = 0.5 m, S = 0.001, and A = 2 m², what is the approximate discharge Q?
- 1.22 m³/s (Correct answer)
- 2.44 m³/s
- 0.61 m³/s
- 3.66 m³/s
Correct answer: 1.22 m³/s
V = (1/n)R^(2/3)S^(1/2) = (1/0.013)(0.5)^(2/3)(0.001)^(1/2) ≈ 0.613 m/s; Q = VA = 0.613×2 ≈ 1.23 m³/s.
Question 5: A soil sample has a void ratio of 0.65 and a specific gravity of 2.70. What is the dry unit weight (γ_d) in kN/m³?
- 14.5 kN/m³
- 16.0 kN/m³ (Correct answer)
- 17.5 kN/m³
- 12.8 kN/m³
Correct answer: 16.0 kN/m³
γ_d = G_s × γ_w / (1+e) = 2.70 × 9.81 / (1+0.65) = 26.487/1.65 ≈ 16.1 kN/m³.
Question 6: In structural steel design (AISC LRFD), what load combination typically governs for a building with significant live load?
- 1.4D
- 1.2D + 1.6L (Correct answer)
- 0.9D + 1.0W
- 1.2D + 1.0E + 0.5L
Correct answer: 1.2D + 1.6L
The combination 1.2D + 1.6L typically governs for gravity load–dominated structures with significant live loads per ASCE 7.
Question 7: The critical path in a CPM schedule is defined as the sequence of activities that:
- Has the most activities
- Has the highest total cost
- Has zero total float (Correct answer)
- Has the most resources
Correct answer: Has zero total float
The critical path consists of activities with zero total float, meaning any delay in these activities will delay the project completion date.
Civil Engineering PE Basic Civil Engineering PE 2
A simply supported beam spans 20 ft and carries a uniformly distributed load of 2 kip/ft.
What is the maximum bending moment?