针对此次汶川地震震害调查中发现的大量施工缝部位震害现象.对现浇钢筋混凝土结构中不可避免存在的施工缝的受力机理展开研究.目前对钢筋混凝土结构进行数值分析时,均不考虑施工缝的影响,按照结构一次性整体浇筑进行建模,这与实际情况不符.为了找出震害原因,通过分析施工缝部位混凝土和钢筋两种类型材料的受力特点和在地震作用下各自承担力的情况,建立相应的简化力学模型.引用摩擦的粘着犁沟理论解决缝面的剪力传递问题.基于常用的有限元分析软件,给出设置施工缝单元需要考虑材料非线性的方法.对一根带缝试验柱建摸进行非线性分析,验证了本文提出的建模方法是可行的.
According to the seismic damage investigation in Wenchuan, the effect of construction joints which can't be avoided in cast-in-situ reinforced concrete structure should be noted. The influence of construction joints is not considered in regular nonlinear numerical simulation, which deviates from the truth. Through analysis of stress characteristics of rebar and concrete, this thesis develops a mechanics model describing the seismic response of joints, so as to find out the cause of earthquake damage. On this basis, it builds up the finite element model of construction joints applied to massive structure. The results show that this new analysis method can help obtain better interpretations with earthquake disaster phenomena.