3材料屈服与破坏的探索_高红.pdfVIP

25 12 Vol.25 No.12 2006 12 Chinese Journal of Rock Mechanics and Engineering Dec .2006 1 12 1 (1. 430071 2. 400041) 3 3 TU 432 A 1000 6915(2006)12 2515 08 EXPLORATION ON YIELD AND FAILURE OF MATERIALS 1 12 1 GAO Hong ZHENG Yingren FENG Xiating (1. Key Laboratory of Rock and Soil MechanicsInstitute of Rock and Soil Mechanics Chinese Academy of SciencesWuhanHubei 430071 China2. Department of Civil Engineering Logistical Engineering University of PLA Chongqing400041 China) Abstract Based on the analysis of yield and failure of materials it is concluded that the two conceptions are differentand they are two different steps in the deformation process of materials. Initial yield is a symbol of materials to first enter into plastic state from elastic state and it is the upper limit of materials′ elastic deformation. So initial yield is the dividing point of elastic state and plastic state. Howeverfailure is the final result of plastic process and it is the limit state that plastic deformation can arriveshowing materials′ limit deformation ability. It is not definite for materials to fail after being yielded because there is a plastic deformation process between yield and failure. Similarlyfailure criteria should be different from yield criteria. But the so-called failure criteria are virtually yield criteria. Therefore it is necessary to properly understand the relations between yield and failureand establish real failure criteria that are not the same as yield criteria. The distinction and interrelation between yiel