模拟地震振动台模型试验是研究桥梁桩墩结构抗震设计的重要方法。振动台试验结果的有效性取决于模型结构与原型结构的相似程度,不同的试验目的对应的相似关系也有差别。桥梁水下桩墩结构动力模型试验在满足结构自身相似律的同时,也要满足结构周围动水压力的相似,水体的存在限制了试验模型的相似设计。基于目前广泛应用的Buckinghamπ定理,采用量纲分析法和方程分析法,通过对比分析,在合理假设的基础上得出了桥梁混凝土桩墩结构振动台破坏试验模型设计的实用相似关系。最后,以某实际水下桥梁桩墩结构为例,通过计算分析验证了相似关系公式并对产生的误差进行了判断。结果表明:原型结构与模型结构的地震动力响应满足预计的相似关系;推导的相似律能在一定程度上避免模型设计的困难,较适用于实际应用。
The model test of seismic simulation shaking table is a important method to research the seismic design of pier structure. The different similitude laws correspond to the different test objective and impact the validity of test results. The water limits the simulation design of test model of pile pier structures in water, because the simulation laws of structure itself and hydrodynamic pressure should be satisfied simultaneously. In order to derive the simili- tude laws of shaking table scale model failure test of the concrete pile-pier structures, based on the theorem of Buckingham w widely used at present, the dimensional and equational analysis method are used contrastively and reasonable hypotheses are proposed. Furthermore, with an actual underwater concrete pier example, the similitude laws are validated and the error is estimated. The results show that the seismic responses of prototype and model satisfy the similitude laws derived. The similitude laws derived can avoid the difficulty for designing the model and are suitable for practical application.