General Model of Fuzzy Plasticity

作     者：ZHANG Chunliang ZHANG Liangchi 

作者机构：School of Mechanical and Electrical Engineering Guangzhou University Guangzhou 510006 China School of Mechanical and Manufacturing Engineering The University of New South Wales Sydney NSW 2052 Australia 

出 版 物：《Chinese Journal of Mechanical Engineering》 (中国机械工程学报（英文版）)

年 卷 期：2010年第23卷第4期

页      面：496-504页

核心收录：

学科分类：12[管理学] 1201[管理学-管理科学与工程(可授管理学、工学学位)] 0817[工学-化学工程与技术] 08[工学] 0807[工学-动力工程及工程热物理] 0802[工学-机械工程] 0811[工学-控制科学与工程] 081201[工学-计算机系统结构] 0801[工学-力学（可授工学、理学学位）] 080102[工学-固体力学] 0812[工学-计算机科学与技术（可授工学、理学学位）] 

基　　金：supported by National Hi-tech Research and Development Program of China (863 Program  Grant No. 2008AA04Z407) 

主　　题：plasticity theory fuzzy model membership function plastic modulus stress-strain curve 

摘      要：The transition between the elastic and plastic states is sharp in the classical plasticity theory. To overcome this problem, many constitutive models, such as multi-yield-surface model and two-surface model, have been developed. However, these models can not represent the true deformation process in a material. In order to capture nonlinear hardening behavior and smooth transition from elastic to plastic state, a general model of fuzzy plasticity is developed. On the basis of the theory of fuzzy sets and TAKAGI-SUGENO fuzzy model, a fuzzy plastic model for monotonic and cyclic loadings in one dimension is established and it is generalized to six dimensions and unsymmetric cycles. The proposed model uses a set of surfaces to partition the stress space with individual plastic modulus. The plastic modulus between two adjacent surfaces is determined by a membership function. By means of a finite number of partitioning surfaces, the fuzzy plastic model can provide with a more realistic and practical description of the materials behavior than the classical plasticity model. The validity of the fuzzy plastic model is investigated by comparing the predicted and experimental stress-strain responses of steels. It was found that the fuzzy plasticity has the ability to handle many practical problems that cannot be adequately analyzed by the conventional theory of plasticity.