高速公路隧道下伏小煤窑采空区洞内注浆处治技术  

Grouting treatment technology of small coal mine goaf beneath expressway tunnel

作　　者：苟德明[1] 田娇[1] 李佳佳 张永兴[2] GOU Deming;TIAN Jiao;LI Jiajia;ZHANG Yongxing(Guizhou Transportation Planning Survey&Design Academy Co.Ltd.,Guiyang 550082,China;Nanjing Forestry University,Nanjing 210037,China)

机构地区：[1]贵州省交通规划勘察设计研究院股份有限公司,贵阳550082 [2]南京林业大学,南京210037

出　　处：《林业工程学报》2018年第5期142-149,共8页Journal of Forestry Engineering

基　　金：国家自然科学基金(51578292)

摘　　要：高速公路隧道下伏小煤窑采空区对衬砌结构稳定影响较大,给隧道施工带来较大风险与潜在危害,按现行技术细则要求对下伏采空区处治范围大、费用高、施工难。笔者以鱼洞Ⅰ号隧道为实例,根据下伏小煤窑采空区规模和特点提出隧道开挖后洞内注浆进行处治措施,通过洞内物探、钻探等手段探明采空区具体位置,采用数值模拟对洞内注浆处治效果进行分析,通过工程实践保证了隧道施工及结构安全。结果表明:隧道下伏采空区对隧道围岩及衬砌结构稳定性影响较大,使得隧道围岩及支护结构最大竖向位移分别达到-0.223 8 m和+0.312 2 m,隧道底板与采空区顶板之间的围岩大部分处于塑性变形状态;现行隧道下伏采空区稳定性评价及处治范围偏于保守,地表注浆处治费用高、难度大;隧道洞内注浆处治下伏小煤窑采空区具有较好效果,隧道结构变形处于可接受范围,可保证隧道施工及结构安全。对于无序开采、资料匮乏、回采率低等隧道下伏小煤窑采空区,采取洞内注浆措施进行处治,可显著减小采空区处治费用及施工难度,为类似工程建设提供参考和借鉴。The goaf of small coal mine beneath expressway tunnel has obvious influence on the stability of tunnel lining structure,and it has brought great risk and potential hazard during the tunnel construction.According to the current technical specification,the treatment scope of goaf was large,the cost was high,and the treating construction was difficult.In this study,Yudong No.1 Tunnel was taken as an example,and the grouting measures in the tunnel were put forward according to the scale and characteristics of goaf in the small coal mine.The specific location of goaf was verified by the geophysical prospecting,drilling and other means beneath the tunnel,which was used to provide guidance for the tunnel design and construction.Moreover,the grouting effect beneath the tunnel was analyzed by the numerical simulation,in which the tunneling stability and corresponding grouting treatment technique were implemented under the conditions of small coal mine goaf beneath the tunnel.In addition,the varied stability of tunnel and tunnel structure before and after grouting treatment technique were compared.The tunnel construction and structural safety are ensured through this engineering practice.The results show that the goaf beneath tunnel had great influence on the stability of tunnel surrounding rock and lining structure,and the proposed grouting treatment technique was effective to avoid the damages caused by small coal mine goaf beneath the tunnel.This ensured the safe tunnel construction in the field practice.The existing stability evaluation and treatment range of goaf beneath tunnel were conservative,and the cost of surface grouting treatment was high with large difficulty.Effects of grouting work in the tunnel were better in treating small coal mine goaf,which ensured the safe tunnel construction and structural safety.For the disorderly mined goaf beneath tunnel with the difficulties of data shortage and lower recovery rate,the grouting treatment in the tunnel could be taken for significantly lowering the cost and constru

关 键 词：高速公路 隧道 小煤窑 下伏采空区 洞内注浆 

分 类 号：U455.4[建筑科学—桥梁与隧道工程]