预制拼装PC箱型墩地震响应的设计参数影响分析

Influence analysis of design parameters on seismic response of prefabricated PC box pier

在收集预制拼装PC箱型墩试验资料的基础上,采用Opensees软件对试验过程进行模拟,验证了有限元模拟方法的可靠性,在此基础上进行参数分析,结果表明:采用并联弹簧可以较为准确地模拟预制拼装箱型墩接缝处的实际力学行为,基于柔度法的纤维梁柱单元模型对于预应力预制拼装桥墩墩顶位移、预应力响应的模拟效果较好;恒载轴压比的提高不利于构件抗震;纵筋配筋率的提高有利于预制拼装箱型墩构件抵抗强度较高地震,对于抗震设防要求较高地区,可以考虑适当提高纵筋配筋率;对于预应力预制拼装混凝土箱型墩,初始预应力的提高超过一定值后不利于结构抗震。相关研究结果可为预制拼装PC箱型墩的抗震研究和工程设计提供参考与借鉴。

On the basis of collecting the test data of prefabricated assembled PC box pier,the test process is simulated by Opensees software,and the reliability of the finite element simulation method is verified.On this basis,the parameter analysis is carried out.The results show that the practical mechanical behavior of the joints of prefabricated box piers can be simulated accurately by using parallel spring,and the displacement of prestressed prefabricated piers is affected by fiber beam and column element model based on flexibility method.The simulation effect of prestress response is good;the increase of dead load axial compression ratio is not conducive to the seismic resistance of members;the increase of reinforcement ratio of longitudinal reinforcement is beneficial to the prefabricated box-type pier members to resist high earthquake intensity,and the seismic fortification requirements are higher in areas,for prefabricated concrete box piers,the increase of initial prestress over a certain value may lead to concrete breakage,which may lead to the reduction of member stiffness.It is unfavorable to the earthquake resistance of the structure.The results can be used as reference for seismic research and engineering design of prefabricated PC box piers.