A review on stress-driven nonlocal elasticity theory

The behavior of materials at the nanoscale cannot be studied by classical theories. Accordingly, new theories have been developed to predict the behavior of materials at the nanoscale; some of them are nonlocal elasticity, strain gradient theory, couple stress theory, and surface effect theory. In most articles, the authors use a differential form of nonlocal elasticity theory. Recently, many authors have used the integral form of this theory and obtained interesting results. Therefore, in the present research, the articles related to the integral form of non-local theory have been examined for small-scale tubes, beams, shells, and plates.