天津市汉南路桥梁场地工程地质条件及土层地震反应分析

Analysis of engineering geological conditions and seismic response of soil layers at the bridge construction site on Hannan Road

汉南路改线及配套服务区项目为天津市建设世界一流大港集疏运北部通道基础设施工程,工程沿线有北疆电厂专用线铁路桥和南堡铁路大桥。汉南路桥梁工程作为重要生命线工程,需在工程建设开始前进行场地地震安全性评价。本文综合前人在区域范围内地震活动性和地震构造研究成果,基于场地地震工程钻孔勘探与测试数据,建立了场地土层一维波动模型,完成了场地地表地震反应计算,取得主要成果:1)两个桥梁工程场地50年超越概率10%对应的地表水平加速度峰值分别为0.209g和0.213g;2)工程全线均位于地震动峰值加速度分区中的0.2g区。汉南路桥梁场地土层地震反应分析工作为后续工程建筑规划、震害预测和抗震设计提供了重要依据,对场地地震地质灾害评价具有重要意义。

The Hannan Road Re-routing and Supporting Service Area Project is an infrastructure project of northern collection and evacuation corridor for Tianjin to build a world-class port,with the railway bridge for Beijiang Power Plant Dedicated Line and Nanbao Railway Bridge along the project route.As an important lifeline project,it is necessary to carry out a site seismic safety evaluation before construction.Combining previous research on seismic activity and tectonics in the region,this paper utilized on-site seismic engineering borehole exploration and test data,build a one-dimensional soil layer fluctuation model and conducted site surface seismic response calculations.According the result,the ground horizontal acceleration peak values at two bridge construction site correspond to a 10%probability of exceeding within 50 years are 0.209g and 0.213g,and the entire project area falls within zoning with peak ground acceleration value of 0.2g.The seismic response analysis provided essential insights for subsequent building planning,seismic risk prediction,and seismic design,which also showed great significance for the evaluation of the seismic geological hazards of the site.