How do you calculate the quantity of cement, sand, and aggregate for 1m³ of concrete? What is the difference between one-way and two-way slabs? How is the development length calculated? What is anchorage length, and why is it important? How do you determine the spacing of stirrups in beams? What is the difference between clear cover and effective cover? What is the standard reinforcement cover for slabs, beams, column. How do you test the quality of cement on-site? What are the different tests conducted on fresh and hardened concrete? What is the compressive strength of M20, M25, and M30 grade concrete after 7 and 28 days? What is the water-cement ratio, and how does it affect concrete strength? How do you check the quality of steel reinforcement before using it in construction? What are the permissible limits of silt content in sand? What is the standard procedure for conducting a slump test? How do you ensure concrete curing

Question

Accepted Answer

Calculating material quantities, slab types, reinforcement details, and quality testing in civil engineering.

Quantity of cement, sand, and aggregate for 1m³ of concrete is calculated by the mix design method.
One-way slabs are supported on two opposite sides, while two-way slabs are supported on all four sides.
Development length is calculated based on the diameter of the reinforcement bar and the grade of concrete.
Anchorage length is the length of the bar required to transfer the load to the concrete. It is important for the stability of the structure.
Spacing of stirrups in beams is determined based on the design requirements and load calculations.
Clear cover is the distance between the outer surface of the concrete and the reinforcement, while effective cover is the distance between the outer surface and the main reinforcement.
Standard reinforcement cover for slabs, beams, and columns is typically around 25mm to 50mm.
Quality of cement on-site can be tested by conducting tests like the fineness test, consistency test, and setting time test.
Tests conducted on fresh concrete include slump test, air content test, and temperature test. Tests on hardened concrete include compressive strength test, flexural strength test, and water absorption test.
Compressive strength of M20, M25, and M30 grade concrete after 7 and 28 days varies based on the mix design and curing conditions.
Water-cement ratio affects concrete strength, with lower ratios generally leading to higher strength.
Quality of steel reinforcement can be checked by verifying the dimensions, weight, and grade of the bars before use.
Permissible limits of silt content in sand are typically around 3-8%.
Standard procedure for conducting a slump test involves filling a mold with concrete, compacting it, removing the mold, and measuring the slump.
Concrete curing is ensured by methods like ponding, spraying, covering with wet burlap, or using curing compounds.

Popular interview questions of Senior Executive and Civil Engineer