BArch Bachelor of Architecture Structural Systems & Engineering 2 — Questions and Answers
Question 1: Which foundation type is most appropriate when a building's loads must be transferred through weak surface soils to deeper, stronger strata?
- Deep pile foundation (Correct answer)
- Spread footing
- Mat foundation
- Grade beam
Correct answer: Deep pile foundation
Pile foundations transfer structural loads through weak upper soils to deeper, competent bearing strata via long slender elements driven or cast into the ground.
Question 2: In steel construction, what does the designation W12×50 indicate?
- Wide flange section, 12-inch nominal depth, 50 lb/ft weight (Correct answer)
- Width 12 inches, 50-kip capacity
- 12-gauge steel, 50-foot span
- 50-inch wide flange at 12 lb/ft
Correct answer: Wide flange section, 12-inch nominal depth, 50 lb/ft weight
W12×50 denotes a wide-flange (W-shape) steel section with an approximate 12-inch nominal depth and a weight of 50 pounds per linear foot.
Question 3: What structural phenomenon occurs when a slender column fails due to lateral deflection before reaching its material strength limit?
- Buckling (Correct answer)
- Yielding
- Creep
- Fatigue
Correct answer: Buckling
Buckling is the sudden lateral deflection and collapse of a slender column under compressive load, governed by Euler's critical load formula.
Question 4: A post-tensioned concrete slab differs from a conventionally reinforced slab primarily because:
- High-strength steel tendons are stressed after the concrete cures (Correct answer)
- Rebar is placed above the neutral axis only
- No steel reinforcement is used
- Concrete is poured in prestressed molds
Correct answer: High-strength steel tendons are stressed after the concrete cures
In post-tensioned slabs, steel tendons are threaded through ducts cast in the concrete and then tensioned after the concrete has hardened, placing the slab in compression.
Question 5: Which structural system is characterized by curving, thin shell concrete that achieves strength through geometry rather than mass?
- Shell structure (Correct answer)
- Moment frame
- Flat slab
- Composite deck
Correct answer: Shell structure
Shell structures derive structural efficiency from their double-curved geometry, distributing loads through membrane action with very thin concrete sections.
Question 6: In seismic design, what does IBC's Seismic Design Category (SDC) determine for a building?
- The required level of seismic resistance and structural detailing (Correct answer)
- Only the foundation type required
- The building's height limit
- Required fire resistance ratings
Correct answer: The required level of seismic resistance and structural detailing
The Seismic Design Category (SDC) assigned by the IBC determines the permissible structural systems, detailing requirements, and height limits for a building based on seismic risk.
BArch Bachelor of Architecture Structural Systems & Engineering 2
Which foundation type is most appropriate when a building's loads must be transferred through weak surface soils to deeper, stronger strata?