The developments of the computational micromec hanics are characterized by the progress of the finite element computational micromechanics (FECM). This paper generalizes the achievements of FECM in the analysis of the mechanic behaviors of composites in recent decades. The models and methods of FECM are instructed, and the paper puts emphasis upon evaluating new numerical results of strength and demage of composites. Finally, the FECM application to the design of new advanced materials is prospected.

The leak before break (LBB) analysis of pressurized piping and vessels, which is developed during the past two decades, is an important advanced technology for the safety of structures in nuclear reactors. In this paper, the state of the art status of research and application of LBB technology is described. Some typical LBB analysis methods and some important problems in LBB analysis process, especially those related to fracture mechanics are discussed. These problems includes the stability analysis of cr...