【摘要】 本文将混凝土视为粘弹性材料,同时考虑外界载荷持续作用下发生的蠕变变形和温度变化引起的应力松弛共同对裂纹扩展过程的影响.根据柘溪大坝的各项实测资料,按照文献[1、2],进行了平面应变的有限元计算,其结果与实测值基本一致. 计算结果表明,柘溪大坝坝墩存在着因水泥水化热及气温变化而造成的迎水面垂直初始表面裂纹,其深度达70—80cm,在1969年元月份的温度应力和水载荷共同作用下,裂纹进一步扩展,当水沿新张开的裂纹渗入到180—240cm时,裂纹扩展的深度达270—294cm.俟后,由于气温和水位的下降,小于330cm深度以内的裂纹停止扩展,到1969年6月份水位回升到164cm高程,在温度应力与水载荷共同作用下,深度达275—282cm以上的裂纹发生失稳扩展.更多还原

【Abstract】 According to the theory of rheologica] fracture, concrete is considered as a viscoelastic material in this paper, the effects on crack propagation of creep delormation and of temperature induced stresses are considered. By use of a plane strain FE model, the crack propagation in the Zhexi dam is computed and compared to the observed crack patterns. Calculated results are consistent with the observed crack.更多还原