What is the primary purpose of providing development length in reinforcement?
A Improve aesthetics
B Ensure bond strength
C Increase concrete strength
D Reduce cost
Development length is the length of reinforcement embedded in concrete to ensure proper bond strength. It allows the transfer of stresses between steel and concrete, preventing slippage and ensuring structural integrity under load.
Which of the following is a characteristic of deep beams?
A Low reinforcement ratio
B No shear reinforcement
C Span-to–depth ratio < 2
D Span-to–depth ratio > 4
Deep beams have a span–to–depth ratio of less than 2. They behave differently from ordinary beams, with significant shear deformations and a non–linear stress distribution, requiring special design considerations.
What is the main purpose of a retaining wall?
A Resist lateral earth pressure
B Improve aesthetics
C Support vertical loads
D Reduce foundation depth
Retaining walls are designed to resist lateral earth pressure and hold back soil or other materials. They are commonly used in terrains, highways, and basements to prevent soil erosion and slope failure.
Which of the following is a common cause of cracking in concrete?
A Low water–cement ratio
B High compressive strength
C High bond strength
D Shrinkage
Cracking in concrete is often caused by shrinkage, which occurs due to the loss of moisture during curing. Other causes include thermal stresses, overloading, and inadequate reinforcement.
What is the primary function of a pile cap?
A Improve soil strength
B Reduce foundation depth
C Transfer loads to piles
D Increase concrete strength
A pile cap is a thick concrete mat that distributes the load from a column or wall to a group of piles. It ensures uniform load transfer and provides stability to the foundation system.
Which of the following is a key factor in the durability of concrete?
A High shrinkage
B Low permeability
C Low compressive strength
D High water–cement ratio
Durability of concrete depends on its ability to resist the ingress of harmful substances like water, chemicals, and gases. Low permeability, achieved through proper mix design and curing, enhances durability.
What is the primary purpose of torsion reinforcement in beams?
A Reduce deflection
B Resist twisting forces
C Improve bond strength
D Resist bending moments
Torsion reinforcement, such as closed stirrups and longitudinal bars, is provided in beams to resist twisting forces caused by eccentric loads or uneven support conditions, preventing structural failure.
Which of the following is a common method for structural retrofitting?
A Adding new columns
B Applying fiber–reinforced polymers (FRP)
C Reducing loads
D Increasing water–cement ratio
Structural retrofitting involves strengthening existing structures. FRP wrapping is a common technique that enhances the load–carrying capacity and ductility of beams, columns, and slabs without adding significant weight.
What is the primary purpose of a water tank in reinforced concrete design?
A Increase soil strength
B Improve aesthetics
C Reduce foundation depth
D Store water
Reinforced concrete water tanks are designed to store water for domestic, industrial, or firefighting purposes. They must be leak–proof, durable, and capable of withstanding hydrostatic pressure.
Which of the following is a key consideration in earthquake–resistant design?
A High shrinkage
B Low reinforcement ratio
C Ductility
D High stiffness
Ductility is crucial in earthquake–resistant design as it allows structures to undergo large deformations without sudden failure. This helps dissipate seismic energy and prevents collapse during earthquakes.
What is the primary purpose of the working stress method?
A Limit stresses under service loads
B Reduce deflection
C Increase ductility
D Ensure ultimate strength
The working stress method ensures that stresses in concrete and reinforcement remain within permissible limits under service loads. It focuses on elastic behavior and prevents excessive cracking or deflection.
Which of the following is a common type of foundation for high–rise buildings?
A Isolated foundation
B Strip foundation
C Raft foundation
D Pile foundation
Pile foundations are commonly used for high–rise buildings to transfer heavy loads to deep, stable soil strata or rock. They provide stability and prevent excessive settlement.
What is the primary purpose of reinforcement detailing?
A Reduce concrete strength
B Ensure proper placement of bars
C Improve aesthetics
D Increase shrinkage
Reinforcement detailing involves specifying the size, spacing, and arrangement of reinforcement bars. It ensures proper load transfer, structural integrity, and compliance with design requirements.
Which of the following is a common cause of deflection in beams?
A High bond strength
B High compressive strength
C Low reinforcement ratio
D Low water–cement ratio
Excessive deflection in beams is often caused by insufficient reinforcement or a low reinforcement ratio. It can also result from overloading, improper design, or inadequate stiffness.
What is the primary purpose of a flat slab in reinforced concrete design?
A Reduce construction time
B Reduce bond strength
C Improve aesthetics
D Increase deflection
Flat slabs are used to reduce construction time and costs by eliminating beams. They provide a flat ceiling surface, allowing flexible partitioning and easier installation of services.