Abstract
Inspired by work of Payen et al.1),2), this paper seeks to make mechanical interpretation of nodal force, in order to more accurately evaluate stress field using linear element of finite element analysis. A new mechanical interpretation is presented for nodal forces, which is an abstract quantity with a rigorous mathematical definition. Use of Lagrangean and particle discretization scheme reveals that nodal force gives total force acting on middle plane of element. Based on the aforementioned interpretation, this paper proposes a method for more accurately evaluating stress field. Numerical experiments indicate that stress field of proposed method is smoother and accurate compared to ordinary element stress evaluation. Moreover, it is found that the error of J-integral, for a mode-I crack problem, is several times smaller when estimated with nodal force based stress evaluation.
