Cracking in reinforced concrete members is attributable to various causes, particularly:
flexural tensile stress due to bending under applied loads;
diagonal tension due to shear and torsion;
direct tensile stress under applied loads (for example, hoop tension in a circular water tank);
lateral tensile strains accompanying high compressive stress/strain due to the Poisson effect (as in a compression test) or due to heavy concentrated loads as in a split cylinder test;
restraint against volume changes due to shrinkage and temperature, as well as due to creep and chemical effects; and
additional curvatures due to continuity effects, settlement of supports, etc.