SCE Structural Engineering 1 — Questions and Answers
Question 1: A simply supported beam of span 8 m carries a uniformly distributed load of 10 kN/m. What is the maximum bending moment?
- 80 kN·m (Correct answer)
- 160 kN·m
- 40 kN·m
- 320 kN·m
Correct answer: 80 kN·m
Maximum bending moment for a simply supported beam with UDL = wL²/8 = 10×8²/8 = 80 kN·m.
Question 2: Which of the following best describes the condition of a 'statically determinate' structure?
- Reactions and internal forces can be found using equilibrium equations alone (Correct answer)
- The structure has more unknowns than equilibrium equations
- The structure cannot be analyzed without material properties
- The structure has redundant members that carry no load
Correct answer: Reactions and internal forces can be found using equilibrium equations alone
A statically determinate structure has exactly as many unknowns as equilibrium equations, so all reactions and internal forces can be solved without material properties.
Question 3: In reinforced concrete design, the term 'balanced section' refers to:
- A section where concrete crushing and steel yielding occur simultaneously (Correct answer)
- A section with equal amounts of tension and compression steel
- A section where the neutral axis is at mid-depth
- A section with minimum reinforcement ratio
Correct answer: A section where concrete crushing and steel yielding occur simultaneously
A balanced section is one in which the extreme concrete fiber reaches its crushing strain (0.003) at the same time the tension steel reaches its yield strain.
Question 4: What is the slenderness ratio of a column, and which value typically indicates a 'long' (slender) column?
- KL/r; values greater than 120 are typically considered long columns (Correct answer)
- L/b; values greater than 50 indicate a long column
- KL/d; values greater than 30 indicate a long column
- L/r; values less than 20 indicate a long column
Correct answer: KL/r; values greater than 120 are typically considered long columns
Slenderness ratio = KL/r, where K is the effective length factor, L is column length, and r is radius of gyration; values above about 120 generally classify a column as slender.
Question 5: According to limit state design philosophy, the ultimate limit state (ULS) is primarily concerned with:
- Structural collapse or failure of the structure (Correct answer)
- Excessive deflection under service loads
- Cracking of concrete under normal conditions
- Vibration comfort of occupants
Correct answer: Structural collapse or failure of the structure
The ultimate limit state addresses structural safety against collapse, including yielding, buckling, fracture, and overturning.
Question 6: A cantilever beam of length 4 m carries a point load of 20 kN at its free end. What is the maximum shear force?
- 20 kN (Correct answer)
- 80 kN
- 40 kN
- 10 kN
Correct answer: 20 kN
For a cantilever beam with a point load P at the free end, the maximum shear force equals P = 20 kN, occurring throughout the entire length.
Question 7: Which structural system transfers loads primarily through axial tension or compression with negligible bending?
- Truss (Correct answer)
- Frame
- Beam
- Plate
Correct answer: Truss
Trusses are designed so that all members carry purely axial (tensile or compressive) forces, with loads applied only at joints to minimize bending.
SCE Structural Engineering 1
A simply supported beam of span 8 m carries a uniformly distributed load of 10 kN/m.
What is the maximum bending moment?