Cyclic Behavior of Concrete Shear Walls: A Rational Approach

9711084徐从过去的地震结构故障的证据清楚地表明，剪力墙提供了良好的保护，在地震区的建筑物。 本计画旨在发展一种合理的方法，以了解及预测低剪力墙及框架剪力墙在循环荷载下的行为。 这种方法背后的总体概念是，剪力墙作为一个整体系统的复杂行为，可以通过整合可以学到的东西来阐明，实验，关于它的部件和组件，可视化为膜元件（面板）的组件。 将研究单个膜元件的应力-应变行为，以建立物理和分析模型。 然后将所得模型集成到有限元程序中，以计算和预测指定条件下整个剪力墙的荷载-变形性能。 休斯顿大学于1988年建造了一个独特的通用面板测试仪，特别适合于预期的测试。 将对25块承受循环荷载的墙板进行试验。 膜单元的循环试验结果将用于建立混凝土的循环本构关系。 混凝土的行为，如刚度退化，强度退化，和“捏”的滞回环将被确定，然后用于校准其相应的参数在分析模型建立的El-Borgi。 然后，校准的滞回模型将使非线性有限元计算机程序制定，它可以用来预测整个剪力墙的行为。 美国休斯顿大学和突尼斯突尼斯理工学院将联合开展这项研究。 ***

9711084 Hsu Evidence from structural failures in past earthquakes clearly shows that shear walls offer excellent protection to buildings in seismic regions. This project is to develop a rational approach to understanding and predicting the behavior of low-rise shear walls and framed shear walls under cyclic loading. The overall concept behind this approach is that the complicated behavior of shear walls as a whole system, can be elucidated by integrating what can be learned, experimentally, about its parts and components, visualized as being an assembly of membrane elements (panels). The stress-strain behavior of individual membrane elements will be studied to establish physical and analytical models. The resulting models will then be integrated into a finite element program to compute and predict the load- deformation behavior of whole shear walls under specified conditions. A unique universal panel tester was constructed at the University of Houston in 1988 which is especially suited for the intended testing. A test program of 25 wall panels subjected to cyclic loading will be carried out. The results from the cyclic tests on membrane elements will be used to establish the cyclic constitutive laws of concrete. Concrete behavior such as stiffness deterioration, strength deterioration, and "pinching" of hysteretic loops will be determined and then used to calibrate their corresponding parameters in an analytical model established by El-Borgi. The calibrated hysteretic models will then enable a nonlinear finite element computer program be formulated, which can be used to predict the behavior of whole shear walls. The University of Houston in the United States and the Polytechnic School of Tunisia in Tunisia will jointly carry out this research. ***