The goal of analyzing the instability in complex sheet metal forming is reached using the forming limit stress diagram as criterion in this thesis . some different sheet metal forming parts are analyzed with the developed software , whose results show that the developed software is satisfying for technological analysis of sheet metal forming and the applied module attains the anticipated goal 并用所开发的应用软件成功地对板成形零件的有限元计算结果进行了分析,分析结果表明,用该软件分析板成形零件的失稳情况的结果可以满足板成形工艺分析要求,所开发的应用软件模块达到了预期目的。
Saturated sand are testes in the laboratory under the undrained cyclic loading condition with static - dynamic dual purpose triaxial compression test apparatus , which is designed under the cooperation of hohai university and marui co . ltd japan . the results indicate that the stress path approaches from a initial stress point to the failure lines as cyclic loading goes on , and eventually converges on a certain limiting stress path in the vicinity of the failure lines . the stress - strain curve , however , does not converge on a closed hystersis loop ; the shear strain rapidly increases in looser sand or gradually and continually increases in denser sand 利用河海大学与日本圆井株式会社共同研制的新型的多功能静动三轴仪进行了饱和砂土循环扭剪不排水试验,研究表明,对于松砂,剪应变幅度快速地由微小增加到百分之几甚至百分之十几,对于紧砂,剪应变幅度逐渐地由微小增加到百分之几甚至百分之十几;经试验初步研究表明用初始有效平均正应力归一化的有效应力路径很好的一致性。