Author(s)

C. C. Chamis & L. Minnetyan

Abstract

A new approach is described for evaluating fracture in composite structures. This approach is independent of classical fracture mechanics parameters like fracture toughness. It relies on computational simulation and is programmed in a standalone integrated computer code. It is multiscale, multifunctional because it includes composite mechanics for the composite behavior and finite element analysis for predicting the structural response. It contains seven modules; layered composite mechanics (micro, macro, laminate), finite element, updating scheme, local fracture, global fracture, stress based failure modes, and fracture progression. The computer code is called CODSTRAN (Composite Durability Structural ANalysis). It is used in the present paper to evaluate the global fracture of four composite shell problems and one composite built-up structure. Results show that the composite shells. Global fracture is enhanced when internal pressure is combined with shear loads. Keywords: micro mechanics, laminate theory, thin shells, thick shells, built-up structures, non-linearities. 1 Introduction The global fracture behavior of fiber composite structures has become of increasing interest in recent years, because of the multitude of benefits that composites offer in practical engineering applications such as lightweight airframes, engine structures, space structures, marine and other transportation structures, high-precision machinery, and structural members in robotic manipulators. Composite structures lend themselves to tailoring to achieve desirable characteristics such as a high strength to weight ratio, dimensional

Keywords

micro mechanics, laminate theory, thin shells, thick shells, built-up structures, non-linearities