振动台非线性破坏模型试验影响因素

振动台模型试验是研究工程结构的动力特性和抗震性能的重要手段,针对振动台模型破坏试验中地震动加载方式及材料模型等影响因素进行了研究。分别采用大体积水工混凝土结构和框架结构对一次性强震作用与地震动逐级累积作用下结构损伤差异进行了对比分析。结果表明,对于大体积脆性混凝土结构及框架结构,逐级加载方案及仿真材料模量和强度的相似性均能够保证结构的线弹性动力特性、损伤起始加速度及极限抗震能力的试验要求,但是不能反应结构从损伤发生到失效破坏的中间发展过程。在进行振动台模型试验时,可根据具体试验目的选择相应的简化措施。

Study on Influencing Factors of Nonlinear Failure Model Test on Shaking Table

The seismic loading scheme and constitutive model of emulation material are studied for the dynamic failure model test, and the differences between the damage induced by complete loading and the cumulative damage by step loading are discussed. Examples of a frame structure and a hydraulic concrete structure are used to clarify the damage developing mechanism. The results show that the step loading scheme, similarity of the module, and emulation strength can meet the requirements for the dynamic failure model tests to obtain dynamic characteristics and earthquake acceleration amplitudes that correspond respectively to the damage initiation and ultimate failure, but cannot capture the developing process of failure patterns of the mass concrete structure by a shaking model test. Thus, it is acceptable to adopt some simplified measures according to the test objectives when carrying out a shaking model test.