NCEES Structural Engineering 1 — Questions and Answers
Question 1: According to NCEES PE Structural exam standards, what is the primary purpose of a moment-resisting frame in a building structure?
- To resist lateral loads through bending in beams and columns (Correct answer)
- To carry only vertical gravity loads
- To provide thermal insulation to the structure
- To distribute wind loads to the foundation via diagonal bracing only
Correct answer: To resist lateral loads through bending in beams and columns
Moment-resisting frames resist lateral loads (wind or seismic) through flexural rigidity developed at beam-column connections.
Question 2: In the NCEES PE Structural exam, a simply supported beam with a uniformly distributed load w over span L has a maximum bending moment of:
- wL²/4
- wL²/8 (Correct answer)
- wL²/2
- wL/4
Correct answer: wL²/8
The maximum bending moment for a simply supported beam with UDL is wL²/8, occurring at midspan.
Question 3: Which LRFD load combination from ASCE 7 is typically governing for dead plus live load design per NCEES standards?
- 1.2D + 1.6L (Correct answer)
- 1.0D + 1.0L
- 0.9D + 1.0W
- 1.4D
Correct answer: 1.2D + 1.6L
The ASCE 7 LRFD combination 1.2D + 1.6L is the standard governing combination for dead plus live load scenarios.
Question 4: On the NCEES PE Structural exam, the effective length factor K for a column that is fixed at the base and pinned at the top (sway prevented) is closest to:
- 2.0
- 0.5
- 0.7 (Correct answer)
- 1.0
Correct answer: 0.7
A column fixed at the base and pinned at the top with sway prevented has an effective length factor K ≈ 0.7.
Question 5: In reinforced concrete design tested on the NCEES PE exam, the Whitney stress block depth factor β₁ for concrete with f'c = 4,000 psi is:
- 0.65
- 0.85 (Correct answer)
- 0.75
- 0.90
Correct answer: 0.85
For normal-weight concrete with f'c ≤ 4,000 psi, ACI 318 sets β₁ = 0.85.
Question 6: Which failure mode is associated with a steel beam that has an inadequate lateral bracing interval, as assessed in NCEES structural exams?
- Web crippling
- Lateral-torsional buckling (Correct answer)
- Flexural shear failure
- Bearing failure
Correct answer: Lateral-torsional buckling
Lateral-torsional buckling occurs when compression flanges are not adequately braced and the beam twists out of plane.
According to NCEES PE Structural exam standards, what is the primary purpose of a moment-resisting frame in a building structure?