Conjugate approximation with smoothing for hybrid photoelastic and FEM analysis

摘要

Meaningful visualization of finite element method (FEM) results is important for building the ground for hybrid numerical-experimental techniques. This is not a straightforward procedure for photoelastic analysis as conventional FEM techniques are based on the approximation of nodal displacements, not stresses. Although the displacements are continuous at inter-element boundaries, the calculated stresses are discontinuous due to the operation of differentiation. Conventional FEM would require unacceptably dense meshing for producing sufficiently smooth photoelastic fringe patterns. Therefore, there exists a need for the development of a technique for smoothing the generated photoelastic fringes representing the stress distribution and calculated from the displacement distribution. The proposed smoothing technique is based on the minimization of the augmented residual.