【摘要】 J_I 积分作为裂缝前缘奇异应力场的参数量,是有实际应用价值的。本文应用常应变三角形单元的有限元结果,用三种方法对三点弯曲试件和重力坝坝底裂缝沿不同回路进行了 J_I 计算。结果表明,在单元网格不要求很细的情况下,基本能实现 J_I 的守恒性;积分路经以过单元形心的回路为好;由 J_I 计算得的应力强度因子 K_I 约在12%的误差范围,满足了工程的要求。更多还原

【Abstract】 INTEGRAL J_I,which is referred to as a parameter of singular stress field at the front of crack-tip,has its practical value.In this paper,for three-point moment specimen and the site crack of gravity dam,J_I has been calculated along several contours,applying three methods to treat the results of finite elements.From the J_I results,it can be shown that the approximate independence of J_I may be obtained without the need of fine mesh,and integral path,passing the elements′ center of mass and is much more preferable.The stress intensity factors obtained from J_I can meet the engineering reqirements within the error range of about 12%.更多还原