边界-土-多跨桥梁系统的分区独立内部子结构地震波输入法及验证  

Development and Validation of a Seismic Input Method for Partitioned Independent Internal Substructures of Boundary-soil-multi-span Bridge Systems

作　　者：柳国环[1,2] 费琦翔 LIU Guo-huan;FEI Qi-xiang(Key Laboratory of Intelligent Construction and Operation in Hydraulic Engineering,Tianjin University,Tianjin 300350,China;School of Civil Engineering,Tianjin University,Tianjin 300350,China)

机构地区：[1]天津大学水利工程智能建设与运维全国重点实验室,天津300350 [2]天津大学建筑工程学院,天津300350

出　　处：《中国公路学报》2025年第3期331-342,共12页China Journal of Highway and Transport

基　　金：国家自然科学基金项目(51978461)。

摘　　要：在独立内部子结构法的基础上,进一步提出了分区独立内部子结构法,旨在保证计算精度和土体客观连续性的前提下降低边界-土-多跨桥梁结构开放系统地震分析的工作量。首先,指出了在多支撑结构各基础周围采用地基局部截断模型的弊端和不科学性,澄清了对于边界-土-多跨桥梁系统而言内部子结构法依然存在计算量超大问题的原因;随后,提出了分区独立内部子结构法思想并给出理论表述,该方法实质在于将场地系统划分为不同区域但不截断,由此独立构建对应的分区独立内部子结构并进行等效地震荷载的计算,从而实现不同场地条件下边界-土-多跨桥梁系统地震动的准确输入;最后,通过自由场和边界-土-两跨桥梁结构2个算例验证分区独立内部子结构法的准确性和高效性。结果表明:分区独立内部子结构法计算效率明显增强,避免了以牺牲计算精度为前提的局部截断建模的传统处理方式,解决了应用已有方法计算边界-土-多跨桥梁系统等效地震荷载时计算效率相对低的现实问题,促进了土-结构动力相互作用地震分析方法的发展。This paper develops the Partitioned Independent Internal Substructure(PIIS)method,which aims to enhance computational efficiency when analyzing the seismic response of boundary-soil-multi-span bridge structures while ensuring the objective continuity of the soil and maintaining computational accuracy.We first discuss the boundedness and unscientific nature of local foundation truncation models.This clarifies the reasons for the relatively large computational burden involved in the seismic analysis of boundary-soil-multi-span bridge systems.We next introduce a creative concept for the PIIS method and elaborate on its nature and underlying theory.In essence,this approach divides the site system into different regions without truncation.Independent internal substructures are then established for each region,and equivalent seismic loads are calculated independently.This process achieves the accurate input of seismic motion for the boundary-soil-multiple-span bridge system.Finally,we consider the examples of a free field and a boundary-soil-multi-span bridge structure to verify its accuracy and high-efficiency.The results show that the PIIS method achieves exactly accurate results,significantly improving computational efficiency and avoiding the conventional method of local truncation modeling that comes at the cost of decreasing accuracy.Furthermore,this developed method overcomes the excessive computational burden of the earlier methods for calculating equivalent seismic loads and promotes the development of seismic analysis techniques for soil-structure interaction.

关 键 词：桥梁工程 地震波输入 分区独立内部子结构法 多点地震动 土-结构动力相互作用 等效地震荷载 

分 类 号：U441.3[建筑科学—桥梁与隧道工程]