Development of an Advanced Continuum Theory for Composite Laminates. Phase 2. Volume 1

A continuum theory with a micro-macro structure was developed for composite laminates that satisfies the traction and displacement continuity requirements at interfaces. The interlaminar stresses were included in the model in a natural way and without any ad hoc assumptions. The theory is best suited for thick multi-constituent laminates composed of several thin plies. The built- in micro-structure of the continuum model can account for the effects of curvature and geometric nonlinearity. A set of constitutive relations in terms of material properties of individual constituents was developed which is capable of modeling fiber orientation and stacking sequence. The theory was further expanded to include the effects of temperature where a set of coupled thermo- mechanical field equations with corresponding constitutive relations were derived, The field equations for linearized kinematics and flat geometries were obtained. Development of the theory for cylindrical and spherical geometries is underway.