Abstract
In this paper, we study the well-posedness of various nonlocal integral theories for formulating predictive models of buckling of higher-order refined shear deformation beams. We find that the two popular purely nonlocal models (i.e., strain- and stress-driven strategies) are ill-posed for the problem at hand. As a remedy, their corresponding two-phase local/nonlocal mixture formulations are well-posed for the problem. Numerical results, obtained by the generalized differential quadrature method (GDQM), show that the strain- and stress-driven local/nonlocal mixture model can predict consistent softening and stiffening effects, respectively. Moreover, the two-phase nonlocal influence on the thermal loads is also investigated.