Identify which of the following serves as an underlying assumption for prestressed concrete member design_______________?
Show answer Hide answer
Answer: D. All the above
Explanation
Pre-stressed concrete design assumes plane sections remain plane during bending. Hooke's law applies to both concrete and steel within allowable working stress limits. Small stress variations in tendons due to external loads are safely accounted for. Pre-stressing introduces initial compressive stresses to improve performance. Elastic theory assumptions simplify the analysis of pre-stressed concrete members. Compatibility of strains ensures accurate prediction of stresses under service loads.
Designers apply these fundamental assumptions when calculating pre-stressed girder deflections. Understanding underlying assumptions ensures safe and reliable prestressed concrete structures. Code provisions for pre-stressed members build directly upon these engineering principles. Individual options represent valid assumptions but only cover a portion of the complete set. Selecting a single assumption ignores the other two equally correct foundational rules. Option D correctly encompasses all valid underlying assumptions for pre-stressed design.
- Subject
- Engineering
- Category
- Civil Engineering
- Topic
- —
- Difficulty
- medium
Related questions
Q1. Compute the total lateral pressure per unit run acting on the vertical face of a retaining wall of height h holding back soil of unit weight w___________________?
Show answer Hide answer
Answer: C. wh² [(1 – )/2(1 + sin )]
Integrating active lateral pressure over wall height yields a quadratic total force equation. Rankine pressure coefficient combines with unit weight and height squared. Division by two accounts for the triangular distrib...
Q2. Pick out the incorrect statement from the following options?
Show answer Hide answer
Answer: D. None of these
Retaining wall reinforcement placement follows structural bending moment demands. Stem reinforcement is placed near the earth side to resist active lateral pressures. Toe and heel slabs have steel placed at bottom and to...
Q3. The required spacing of shear stirrups in a rectangular reinforced concrete beam is__________________?
Show answer Hide answer
Answer: D. Increased at the centre of the beam
Shear forces are maximum at support locations and decrease toward the beam center. Required shear stirrup spacing increases as internal shear demand diminishes. Center zones of simply supported beams often require only m...
Q4. The angle of repose for a soil mass is defined as the maximum angle formed by the outer soil slope with_______________?
Show answer Hide answer
Answer: A. With the horizontal
The angle of repose is measured between the natural soil slope and the horizontal plane. Gravity dictates the maximum stable slope angle granular soils can maintain. Horizontal reference planes provide the baseline for g...
Q5. Steel reinforcing bars are spliced together to achieve lengths exceeding standard stock lengths by utilizing_______________?
Show answer Hide answer
Answer: D. All the above
Steel reinforcing bars are spliced using various methods when exceeding stock lengths. Straight bar splices, hooked splices, and dowels all provide required continuity. Contractors select splice types based on bar size a...
Q6. The structural design of the heel slab in a retaining wall relies on the maximum bending moment caused by______________?
Show answer Hide answer
Answer: D. All the above
Heel slabs support the dead weight of the concrete structural element itself. Massive backfill soil resting on top of the heel creates substantial downward loads. Surface surcharge loads add extra downward pressure that...