基于WSS的地铁隧道全强风化花岗岩注浆加固技术

Grouting Reinforcement Technology of Fully Strongly Weathered Granite in Metro Tunnel Based on WSS

地铁隧道在花岗岩全强风化带施工过程中,由于地层强度低、承载力差、抗变形能力弱,若不对其进行有效加固则会使得开挖风险极大。为增强隧道围岩特性,对广州地铁22号线某区间暗挖工程进行了WSS帷幕注浆加固。工程实践结果表明:注浆形成的浆脉使岩土体的压缩模量增强、渗透系数降低,注浆压力对土体的挤压作用则提高了岩土体的整体性和自稳能力;开挖监测得到拱顶竖向最大沉降为+5.7 mm,地表最大沉降为-27.12 mm,达到了施工安全的目标。现场所采用的加固措施对类似地层的注浆加固治理具有一定的参考意义。

During the construction of subway tunnel in the fully weathered granite zone,due to the low stratum strength,poor bearing capacity and weak deformation resistance,if it is not effectively reinforced,the excavation risk will be great.In order to enhance the characteristics of tunnel surrounding rock,WSS curtain grouting reinforcement was carried out in the concealed excavation project in a section of Guangzhou metro line 22.The results of engineering practice show that the grout vein formed by grouting enhances the compression modulus and reduces the permeability coefficient of rock and soil mass,and the extrusion effect of grouting pressure on soil mass improves the integrity and self stability of rock and soil mass.The excavation monitoring shows that the maximum vertical settlement of arch crown is+5.7 mm and the maximum surface settlement is-27.12 mm,which achieves the goal of construction safety.The reinforcement measures adopted in the field have certain reference significance for the grouting reinforcement treatment of similar strata.