What is the main function of shear reinforcement in beams?
A Resist compression
B Prevent bending
C Prevent cracking
D Resist shear forces
Shear reinforcement, such as stirrups, helps resist diagonal shear stresses in beams. Concrete alone is weak in tension, so reinforcement prevents cracking and failure under shear stress, particularly near supports.
Which concrete grade is most commonly used in slabs?
A M20
B M25
C M30
D M15
M20 concrete grade is widely used for slabs due to its strength and durability. With a compressive strength of 20 MPa, it offers good performance for most low to medium-strength applications like slabs.
What does “creep” in concrete affect?
A Cracking
B Strength
C Deflection
D Durability
Creep refers to the gradual deformation of concrete under sustained load over time. It primarily affects deflection, leading to long-term bending or sagging in concrete structures like beams or slabs.
What does reinforcement in concrete resist?
A Compression
B Tension
C Flexural stress
D Shear stress
Reinforcement in concrete is added primarily to resist tensile stresses. Concrete is strong in compression but weak in tension, so reinforcement (typically steel) provides the tensile strength needed for structural stability.
What is the purpose of concrete mix design?
A Quality control
B Aesthetic appeal
C Workability
D Cost reduction
Concrete mix design ensures the correct proportions of materials (cement, water, aggregates) to achieve desired strength, workability, and durability, ensuring the structure performs well under its intended load conditions.
Which factor increases the durability of concrete?
A High temperature
B High shrinkage
C Low permeability
D High water-cement ratio
Low permeability in concrete reduces the ingress of water, chemicals, and gases, which improves its durability. Proper curing and mix design are crucial to achieving low permeability and enhancing the concrete’s lifespan.
What is the primary purpose of a pile foundation?
A Increase stability
B Resist shear
C Reduce cost
D Transfer load
Pile foundations are used to transfer heavy loads to deep, stable soil layers or rock. They are particularly useful when surface soils are weak or prone to excessive settlement under load.
What is the purpose of bond between concrete and reinforcement?
A Increase stiffness
B Transfer load
C Strengthen bond
D Prevent corrosion
The bond between concrete and reinforcement allows the two materials to act together as a composite unit. This ensures that loads are transferred efficiently from the concrete to the reinforcement, allowing for effective load-bearing capacity.
What is the maximum grade of concrete typically used for structural elements?
A M30
B M25
C M35
D M40
M30 concrete grade is commonly used for structural elements, such as beams and columns, where higher strength is required. It provides good resistance to compression and durability in moderate to heavy-load applications.
Which design method is commonly used in reinforced concrete?
A Ultimate stress
B Working stress
C Limit state
D Elastic stress
The limit state design method ensures that reinforced concrete structures meet both strength and serviceability requirements. It accounts for safety under extreme conditions and functionality under normal service conditions.
What is a flat slab’s main advantage?
A Increases stiffness
B Reduces material
C Increases construction time
D Eliminates beams
Flat slabs eliminate the need for beams, resulting in a simpler and faster construction process. This reduces material costs, decreases floor-to-floor height, and provides flexibility in layout and partitioning.
What is torsion reinforcement used for?
A Bending resistance
B Twisting forces
C Axial load resistance
D Shear resistance
Torsion reinforcement is used in beams to resist twisting forces caused by eccentric loads. Twisting can lead to structural instability, and the reinforcement ensures the beam resists these forces without failure.
Which type of slab is supported only on two opposite sides?
A One-way slab
B Two-way slab
C Flat slab
D Cantilever slab
One-way slabs are supported on two opposite sides and transfer loads in one direction. These slabs are used when the length-to-width ratio is large, and the slab acts as a beam in one direction.
Which reinforcement type is commonly used in columns?
A Plain bars
B Tie bars
C Longitudinal bars
D Stirrups
Longitudinal bars are used in columns to resist axial load and bending. These bars run along the length of the column and are essential for providing strength and stability under compressive forces.
What type of foundation is suitable for deep foundations?
A Isolated foundation
B Pile foundation
C Raft foundation
D Slab foundation
Pile foundations are used for deep foundations, where the load from the structure is transferred to deeper, more stable soil layers. They are suitable for sites with weak or compressible surface soils.