The most common admixture used as a retarder to increase the initial setting time of concrete is:

As per IS 456:2000, the maximum admissible water-cement ratio for reinforced concrete under mild environmental exposure is:

What is the characteristic flexural tensile strength (fcr) of M25 grade concrete as per IS 456:2000?

What is the minimum water-cement ratio required for complete hydration and workability of concrete?

According to IS 456:2000, the short-term static modulus of elasticity (Ec) of concrete in N/mm2 is given by:

The curing of concrete is essential because it is the process of:

Match the following concrete exposure conditions with their corresponding environment according to IS 456: A. Moderate - I. Concrete completely immersed in seawater B. Severe - II. Concrete exposed to condensation and rain C. Very severe - III. Surface of concrete member in tidal zone D. Extreme - IV. Concrete exposed to seawater spray

Select the correct arrangement in increasing order of pore/void size in a hydrated cement paste: A - Capillary pores B - Entrapped air C - Entrained air D - Interlayer space in C-S-H

Loss of stress in steel caused by elastic deformation of concrete in pre-stressed concrete is given by: