正盘台隧道超前帷幕注浆合理范围

Reasonable Range of Advanced Curtain Grouting in Zhengpantai Tunnel

富水隧道开挖易引起突涌水、掌子面失稳和支护结构位移过大等问题,采用帷幕注浆可加固围岩并止水,进而保障隧道施工安全。为寻求合理超前帷幕注浆范围,依托京张铁路正盘台隧道实际,通过FLAC3D数值模拟手段建立了渗流场与应力场的耦合模型,研究深埋富水段隧道超前帷幕不同注浆范围对围岩稳定性和渗流规律的影响,从而指导工程实践。研究结果表明:全断面帷幕注浆和全周边注浆可较好满足正盘台隧道不同渗水段安全需求。

The excavation of deep buried tunnel with rich water can easily result in inrush of water,instability of the working face and excessive displacement of the supporting structure,etc.Curtain grouting can reinforce the surrounding rock and stop the water,thus ensuring the safety of tunnel construction.In order to seek the reasonable range of advanced curtain grouting,the fluid-structure coupled model was established by means of FLAC3D on the basis of the actual situation of Zhengpantai tunnel of the Beijing-Zhangjiakou railway.The influence of different pre-grouting ranges of the deep buried water-rich tunnel on the stability of surrounding rock and seepage law was studied,so as to provide guidance for engineering practices.The research result shows that the whole section curtain grouting and peripheral curtain grouting can fairly match the security requirements of different seepage sections of the Zhengpantai tunnel.