不同地震波输入机制下的结构振动台模型试验

Different Input Meshanism of Seismic on Shaking Table Test

设计了一个10层框架结构,直接置于振动台上进行模型试验.讨论不同输入机制对结构地震反应的影响.在进行了土层自由场、土-结构相互作用体系的振动台试验的基础上,选择三种试验记录作为该模型结构振动台试验的台面输入,分别为先期试验中的振动台输入、自由场试验中的地表记录、土-结构相互作用体系试验中模型结构基础上测得的记录.把试验结果与土-结构相互作用体系的试验结果作对比,讨论不同输入模式的合理性.试验结果表明:不考虑土层因素,直接将基岩波作为输入,与实际误差最大,将自由场的反应作为输入时误差有所减小,而将土-结构体系基础上的反应作为输入时结构反应与实际情况更为接近,但有时会低估结构的反应.

A ten-story frame structure is designed for shaking table model test and the influence of different input mechanisms on the seismic responses of the structure are discussed.Based on the free-field tests and soil-structure interaction tests,three waves are selected and used as shaking table model test inputs.They are records used in the former tests,the soil＇s surface records obtained from the free-field tests and the foundation response of soil-structure interaction tests respectively.A comparative study is made of the results with those obtained from soil-structure interaction system and a discussion is held on the reasonableness of the different input mechanisms.The test results show that if the bedrock wave is used as input without considering the soil factor,the maximum error may occur;when free field waves are used as input,the error may reduce;if the time history record at the foundation in the soil-structure system test is used as input,the structure response will be much colser to the soil-structure interaction system,but sometimes the structural response may be underestimated.