BCE Bachelor of Civil Engineering 4 — Questions and Answers
Question 1: Which load combination per ASCE 7 governs the design of most structural members for strength?
- 1.2D + 1.6L (Correct answer)
- D + L
- 0.9D + 1.0W
- 1.4D
Correct answer: 1.2D + 1.6L
The LRFD combination 1.2D + 1.6L typically controls the design of floor members because live load is the dominant variable.
Question 2: In geotechnical engineering, the angle of internal friction (φ) is highest for:
- Soft clay
- Loose sand
- Dense gravel (Correct answer)
- Organic peat
Correct answer: Dense gravel
Dense gravel has high interlocking and friction between particles, giving it the highest angle of internal friction among these options.
Question 3: What is the primary purpose of a weir in open channel flow measurement?
- To increase flow velocity
- To measure discharge by correlating head over the weir (Correct answer)
- To remove suspended sediment
- To control water temperature
Correct answer: To measure discharge by correlating head over the weir
A weir creates a controlled overflow section where the water head above the crest is measured and related to discharge via empirical formulas.
Question 4: In transportation engineering, Level of Service (LOS) A on a roadway describes:
- Forced or breakdown flow near capacity
- Free-flow conditions with little interaction between vehicles (Correct answer)
- Stable flow at or near capacity
- Unstable flow with significant delay
Correct answer: Free-flow conditions with little interaction between vehicles
LOS A represents free-flow conditions where drivers operate with complete freedom to select desired speeds with minimal interaction.
Question 5: Which failure mode of a steel column is characterized by twisting about its longitudinal axis?
- Local buckling
- Flexural buckling
- Torsional buckling (Correct answer)
- Lateral-torsional buckling
Correct answer: Torsional buckling
Torsional buckling involves rotation of the cross-section about the longitudinal axis and governs for open sections with low torsional stiffness.
Question 6: In environmental engineering, BOD (Biochemical Oxygen Demand) measures:
- The total dissolved solids in water
- Oxygen consumed by microorganisms decomposing organic matter (Correct answer)
- The pH buffering capacity of wastewater
- The concentration of heavy metals
Correct answer: Oxygen consumed by microorganisms decomposing organic matter
BOD quantifies the amount of dissolved oxygen consumed by biological processes breaking down organic matter in water over a specified period.
Question 7: The 'Proctor compaction test' is used in geotechnical engineering to determine:
- The shear strength of saturated clay
- The optimal moisture content for maximum dry density (Correct answer)
- The permeability of gravel
- The consolidation rate of soft soil
Correct answer: The optimal moisture content for maximum dry density
The Proctor test establishes the compaction curve, identifying the optimum water content at which soil achieves its maximum dry unit weight.
BCE Bachelor of Civil Engineering 4
Which load combination per ASCE 7 governs the design of most structural members for strength?