新建黄土隧道基底钢管桩加固合理桩长研究  

Study on Reasonable Pile Length for Steel Pipe Pile Reinforcement at Base of New Loess Tunnel

作　　者：张秀俊 ZHANG Xiujun(Shanxi Transportation Holdings Group Co.,Ltd.,Taiyuan,Shanxi 030006,China)

机构地区：[1]山西交通控股集团有限公司,山西太原030006

出　　处：《山西交通科技》2024年第3期97-101,124,共6页Shanxi Science & Technology of Transportation

摘　　要：湿陷性黄土地区新建黄土隧道的明洞及浅埋段湿陷等级高、承载力低,隧道基底承载力往往满足不了设计要求,常采用钢管桩进行基底加固。为研究钢管桩的合理桩长,以某新建黄土隧道为工程背景,通过建立三维有限元分析模型,分别研究了钢管桩长度为4 m、6 m、8 m和12 m四种工况下隧道围岩和复合地基的受力及变形情况。研究结果表明钢管桩长度越大,围岩和复合地基应力稳定值及最终变形量越小,但当钢管桩长度大于6 m时,钢管桩对隧底的加固效果基本相同,围岩和复合地基应力稳定值及最终变形量基本相同,建议钢管桩的合理长度取6~8 m。The open tunnel and shallow buried section of the new loess tunnel in collapsible loess areas have high collapsibility and low bearing capacity,and the tunnel base bearing capacity cannot meet the design requirements,so steel pipe piles are often used for the base reinforcement.To investigate the reasonable length of the steel pipe pile,this paper established a 3D finite element analysis model of a new loess tunnel to study the stress and deformation of the tunnel surrounding rock and the composite foundation under four working conditions of the pile lengths of 4 m,6 m,8 m,and 12 m.The study results showed that the longer the steel pipe pile,the smaller the value of stress stability and final deformation of the surrounding rock and composite foundation.But when the steel pipe pile length was larger than 6 m,the reinforcement effect of the steel pipe pile on the tunnel base was similar,and the value of the stress stability and final deformation of the surrounding rock and composite foundation was identical.So,the suggested reasonable length range of the steel pipe pile is 6-8 m.

关 键 词：黄土隧道 基底承载力 钢管桩 合理桩长 数值模拟 

分 类 号：U457.3[建筑科学—桥梁与隧道工程]