A singly reinforced rectangular concrete beam has a width of $$150$$ $$mm$$ and an effective depth of $$330$$ $$mm.$$ The characteristic compressive strength of concrete is $$20$$ $$MPa$$ and the characteristic tensile strength of steel is $$\,\,\,\,\,\,\,415\,\,MPa.$$

Adopt the stress block for concrete as given in $$IS$$ $$456$$-$$2000$$ and take limiting value of depth of neutral axis as $$0.48$$ times the effective depth of the beam.

The limiting area of tension steel in $$m{m^2}$$ is

A concrete beam of rectangular cross-section of size $$120$$ $$mm$$ (width) and $$200$$ $$mm$$ (depth) is prestressed by a straight tendon to an effective force of $$150$$ $$kN$$ at an eccentricity of $$20$$ $$mm$$ (below the centroidal axis in the depth direction). The stresses at the top and bottom fibres of the section are

Consider the following statements:

1. The compressive strength of concrete decreases with increase in water-cement ratio of the concrete mix.

2. Water is added to the concrete mix for hydration of cement and workability.

3. Creep and shrinkage of concrete are independent of the water-cement ratio in the concrete mix.

The true statements are

Consider the following statements:

I. Modulus of elasticity concrete increases with increase in compressive strength of concrete.

II. Brittleness of concrete increases with decrease in compressive strength of concrete.

III. Shear strength of concrete increases with increase in compressive strength of concrete.

The TRUE statements are