Shaking Table Test allowing Interpretation of Damage to Structure in terms of Energy Influx and Efflux through Soil-Structure Interface

为了在不使用任何物理地面模型的情况下考虑土与结构之间的相互作用，Konagai等人（1997年至1998年）介绍了一种新的振动台试验方法。在他们的方法中，适当的土-结构相互作用运动被添加到自由场地震动中以模拟土-结构相互作用效应。该方法考虑了辐射阻尼，辐射阻尼一般使土-结构体系的总阻尼大于结构本身的阻尼，因此在振动台试验中考虑土-结构相互作用效应，可降低对振动台试验能力的要求。这种动力相互作用是与地震激励产生的能量通过土-结构接触面传递的流入和流出有关的现象。注意到内流和外流之间的差异正是结构内储存的能量，因此，与da的程度密切相关。 关于我们 法师的结构。如果在振动台试验中合理地模拟这些相互作用效应，人们将获得必要的信息来解释原型结构在能量方面的破坏过程。该方法最初是在假设土壤线性行为的基础上发展起来的，在本报告中，该方法通过等效线性方法扩展到考虑“远场”土壤非线性。在基础附近产生的非线性，这通常是与大应变和分离之间的土壤和基础，没有考虑在这项研究。在这种方法中，动态土壤参数是通过数字信号处理器在真实的时间变化。该方法，一方面，捕获在地震过程中软化和再硬化的非线性土壤行为，另一方面，允许测试一个更大的上部结构模型，避免了需要一个沉重的物理地面模型。少

With a view to incorporate the interaction between soil and structure without using any physical ground model, Konagai et al. (1997〜1998) introduced a new method for shaking table tests. In their method, appropriate soil-structure interaction motions are added to free-field ground motions to simulate soil-structure interaction effects. The method considers radiation damping which, in general, causes the total damping of a soil-structure system to be greater than that of the structure itself, Thus the incorporation of soil-structure interaction effects in a shaking table test leads to reducing the demands on the capacity of shaking tables. This dynamic interaction is a phenomenon associated with the influx and efflux of energy which is generated by the earthquake excitation and transmitted through the soil-structure interface. It is noted that the difference between the influx and efflux is exactly the energy stored up within a structure, and thus, is closely related to the extent of da … More mage to the structure. If these interaction effects are rationally simulated in shaking table tests, one will obtain the necessary pieces of information for interpreting the failure processes of prototype structures in terms of energy.The method was initially developed with the assumption that soil behaves linearly in the present report, the method is extended to take the 'far field' soil non-linearity into account through an equivalent linear approach. The non-linearity produced in the vicinity of foundations, which is usually associated with large strain and separation between soil and foundation, has not been considered in this study. In this method the dynamic soil parameters are varied in real time by means of a digital signal processor. The method, on one hand, captures the non-linear soil behavior of softening and re-hardening during the course of an earthquake, and on the other hand, allows testing of a bigger superstructure model by obviating the need of a heavy physical ground model. Less