摘要
为获得大跨度扁平地下工程开挖成洞的施工方法,论文结合断面形式为拱形的某超大跨度扁平地下洞室,提出将进深方向的大跨度洞室变成小跨度洞室的纵向跳格、横向分布的开挖方案,采用数值模拟的方法对考虑洞库纵向跳格的开挖顺序、开挖宽度以及两侧导洞的宽度等因素的9种方案进行了对比计算,并从洞库拱顶位、围岩最大剪应变以及锚索、锚杆的受力情况等几个方面对模拟结果进行了系统分析。结果表明:对于超大跨度扁平地下工程采用顺序跳格、逆序回挖的跳格开挖顺序、纵向跳格开挖宽度取15米左右、两侧导洞宽度取10 m左右较为合理,论文研究结果对同类型大跨度地下工程的开挖成洞具重要的参考价值。
This paper aims to investigate the excavation methods used for underground construction with super large span and flat cross section.Considering the large span of the underground chamber with arch section,the excavation scheme was proposed as follows.In the radial direction,the large span chamber was divided into small span chamber.In the longitudinal direction,the excavation sequence was alternate.Then numerical modeling was used to study the influences of excavation sequence,excavation width and pilot tunnel width by nine calculation cases.The simulation results were systematically analyzed from the vault displacement,the maximum shear strain of the surrounding rock,and the stress of the anchor cable and anchor.The results indicate that the alternate excavation sequence in positive and negative directions is reasonable for super large span small sagittal ratio underground cavern.The excavation width of 15 m and the pilot tunnel width of 10 m are recommended.The results in this paper provide a certain references for the similar underground constructions with large span.
作者
徐干成
袁伟泽
徐景茂
颉旭虎
李成学
Xu Gancheng;Yuan Weize;Xu Jingmao;Xie Xuhu;Li Chengxue(Engineering Design and Research Institute of Air Force Academy,Beijing 100068,P.R. China;Engineer Protective Engineering Institute,Academy of Military Sciences PLA China,Luoyang,Henan 471023,P.R. China)
出处
《地下空间与工程学报》
CSCD
北大核心
2018年第S2期763-768,773,共7页
Chinese Journal of Underground Space and Engineering
基金
军队重点课题资助(BLY211L021)
关键词
大跨度
扁平地下洞室
开挖成洞
纵向跳格
数值模拟
large span
small sagittal ratio underground cavern
excavation methods
alternate excavation sequence
numerical model
