浅埋黄土分岔隧道在不同施工方案下的变形规律研究  

Study on Deformation Law of Shallow-buried Loess Bifurcated Tunnel Under Different Construction Schemes

作　　者：符文亮 张元帅 徐松 葛万杰 Fu Wenliang;Zhang Yuanshuai;Xu Song;Ge Wanjie

机构地区：[1]兰州交通大学土木工程学院,甘肃兰州730070 [2]中铁二十二局集团第一工程有限公司,黑龙江哈尔滨150006

出　　处：《重庆建筑》2023年第11期53-56,共4页Chongqing Architecture

基　　金：国家自然科学基金(41562014)。

摘　　要：为研究浅埋黄土分岔隧道施工过程中的变形规律,该文依托甘肃省兰州市某浅埋分岔铁路隧道工程,采用数值模拟对比分析中导洞法与三导洞法的隧道拱顶沉降、水平收敛及中隔墙水平位移发展情况,优选出最合理的施工方案,以满足施工安全要求。研究结果表明:两种方法施工结束后,目标断面左右洞拱顶沉降值相差不大,但三导洞法左右洞边墙的水平收敛值远小于中导洞法,即三导洞法施工更有利于控制隧道围岩的变形。在左右洞先后施工次序产生的偏压影响下,两种方案的中隔墙均向先行洞倾斜,但中导洞法施工中隔墙偏移值较小,更能确保中隔墙的稳定性。两种方案均能满足要求,但三导洞法工序转换复杂,工期较长,在其他方面结果相差不大的情况下,三导洞法并不是最经济的施工方案,可优先考虑中导洞法。研究成果可为浅埋黄土分岔隧道的设计与施工提供参考。In order to study the deformation law of shallow-buried loess bifurcated tunnels in the construction process,this paper takes a shallow-buried bifurcated railway tunnel project in Lanzhou City,Gansu Province as an example,and uses numerical simulations to compare and analyze the tunnel vault settlement,horizontal convergence and horizontal displacement development with the middle-pilot drift method and the three-pilot tunnel method,so as to choose the most reasonable construction scheme and meet the construction safety requirements.The results showed that after the construction with the two methods,the settlement value of the left and right tunnel vaults of the target section hardly differ,but the horizontal convergence value of the left and right side walls with the three-pilot method is much smaller than that of the middle-pilot drift method,that is,the three-pilot method can better control the deformation of the tunnel surrounding rocks.Under the influence of the bias caused by the construction sequence of the left and right holes,the middle partition walls with the two schemes are inclined to the first hole,but the offset value of the middle partition wall in the construction with the middle-pilot drift method is smaller,which can ensure the stability of the middle partition wall.Both schemes can meet the requirements,but the three-pilot drift method has a complex construction sequence conversion with a long construction period.So in the case of little difference in other aspects,the three-pilot drift method is not the most economical construction scheme,and the middle-pilot drift method can be given priority.The research results can provide reference for the design and construction of shallow-buried loess bifurcated tunnel.

关 键 词：分岔隧道 浅埋黄土 中导洞法 三导洞法 

分 类 号：U455[建筑科学—桥梁与隧道工程]