Meng-g Chen

A novel hybrid finite element analysis of bimaterial wedge problems

Abstract An assumed hybrid-stress finite element model together with a new super singular wedge-tip element with numerical eigensolutions is developed to study the bimaterial wedge/notch problems. The establishment of the super wedge-tip element consists of (1) a finite element method-based eigenanalysis is developed and applied to determine the order of the stress singularity and the angular dependences of the stress and displacement fields, (2) these fields are subsequently used to develop a finite element surrounding the wedge tip. To demonstrate the validity of the method, three types of the bimaterial wedge problems are examined and compared with analytical/referenced solutions. The high accuracy and general applicability of the present technique are shown.

Finite Element Analyses of Multi-Material Wedges and Junctions with Singular Antiplane Stress Field

Some analytical methods can be used to solve singular antiplane stress fields of typical geometrcal discontinuity (e.g., [1]), but they can not be used directly to various kinds of multi-material wedges and junctions. Conventional finite element models with refined meshes near the singular point can be used to predict singualr stresses, but it has long been recognized that the results is not accurate. For this reason, special elements have been created over the years which are especially suited to evaluate the stress state present around the singular point. Among them, singular elements that incorporate the angular variation of the singular fields are more appropriate for dealing with singular stress field problems. However, derivation of analytical angular variations of is either limited to very simple configurations or requiring high level of mathematical competence. Naturally, numerical generated fields is resorted to. It is recommendable that the finite element eigenanalysis method can predict numerical angular variations of muti-material wedges and junctions [2], and recently, a kind of ad doc finite element eigenanalysis method has been established by the authors and used to solve the singulrity orders and the angular variations of multi-material wedges and junctions [3].