Size-dependent stress-driven behaviour of nanobeams based on higher-order theories

In this paper, an efficient nonlocal higherorder shear deformation beam theory is developed for bending of nanobeams based on the stress-driven model. The theory accounts for several distributions of the transverse shear strains that satisfy the zero traction boundary conditions on the surfaces of the beam. Hence, it is not necessary to use a shear correction factor. Collecting the higher-order shear deformation beam theories and the stress-driven nonlocal model, the equations of nonlocal elastic equilibrium are consistently derived. Hence, it is shown that the stress-driven model is well-posed for higher-order shear deformation theories. The accuracy of the present approach is verified by comparing the obtained results with existing solutions. It can be concluded that the present nonlocal stress-driven approach for higher-order shear deformation theory is not only accurate but also simple in predicting the bending behavior of nanobeams.