基于HSS模型的新建墩台对邻近桥墩基础的影响研究
Influence of New Pier Construction on Adjacent Existing High Speed Railway Pier Foundation
王采扣 1黄涛 1常伟 1王海元 1濮仕坤 2翟永勇3
作者信息
- 1. 江苏省地质局第一地质大队,江苏南京 210098
- 2. 陆军工程大学国防工程学院,江苏南京 210098
- 3. 南京勘察工程有限公司,江苏南京 210098
- 折叠
摘要
为了研究新建墩台施工对邻近高铁桥墩基础的影响,首先基于小应变土体硬化模型(hardening soil model with small-strain stiffness,简称HSS模型),利用PLAXIS 3D有限元软件建立新建墩台施工全过程计算模型,然后分析邻近既有线高铁桥墩基础土体位移特性,并与现场监测数据对比验证有限元计算模型的可靠性,最后计算分析墩台和桩体的位移情况.结果表明:基坑开挖过程模拟采用HSS模型,有助于有限元计算中获得较可靠的位移结果;既有高铁桥墩基础土体方面,水平向基坑方向最大水平位移 1.53 mm,最大沉降 5.49 mm.既有墩身和承台最大沉降量小于 6 mm,墩承台总沉降和相邻墩承台差异沉降均小于规范限值.既有桩基础群桩外围顶部向四周产生位移,而中间桩顶部沉降较小,呈"开花式"位移状态.在新建墩台施工过程中,钻孔灌注桩的施工、钢板桩的插拔和基坑回填对既有高铁桥墩基础水平位移和沉降影响较大.
Abstract
To study the influence of new pier construction on adjacent high-speed rail pier foundation,the whole construction process calculation model of the new pier was established based on the hardening soil model with small-strain stiffness(HSS model)and PLAXIS 3D finite element software,and then the soil displacement characteristics of adjacent existing high-speed rail pier founda-tion were analyzed.The reliability of the finite element model was verified by compared with the field monitoring data.The displace-ment of the pier and pile was calculated and analyzed.The results show that the HSS model is helpful to obtain more reliable displace-ment results in finite element calculation.In terms of soil mass,the maximum horizontal displacement and settlement are 1.53 mm and 5.49 mm in the horizontal direction of the foundation pit.The maximum settlement of the existing pier and cap is less than 6 mm,and the total settlement of the pier cap and the differential settlement of the adjacent pier cap is less than the standard limit.The outer top of the pile group of the existing pile foundation has a displacement to the four sides,while the top of the middle pile has a small settle-ment and bears the"open pattern"displacement state.During the construction of the new pier,the construction of the new bored pile,the insertion of the steel sheet pile,and the backfilling of the foundation pit have a great influence on the horizontal displacement and settlement of the existing high-speed railway pier foundation.
关键词
墩台施工/邻近既有高铁线/有限元/桥墩基础/位移分析Key words
pier construction/existing adjacent high-speed railway/finite element/pier foundation/displacement analysis引用本文复制引用
出版年
2024
NETL
NSTL
万方数据