摘要
研究目的:中南地区一硝盐矿区采用水溶法开采地下500 m深度的盐矿,采空区地表变形严重,铁路枢纽货车外绕线拟穿越该矿区,工程风险大.本文基于地表实测变形数据,研究水溶开采诱发地面变形特征,采用自然平衡拱理论结合物探方法分析地面塌陷风险,确定合理的线路通道,并提出穿越深埋水溶采空区铁路的综合防治措施.研究结论:(1)采空区地表存在两个累计沉降量达927 mm和843 mm的沉降中心,沉降中心位于矿柱上,水溶采空区已发生连通;(2)南通道覆岩破坏严重,覆岩垮塌至地面风险高,北通道覆岩相对完整,仅局部井身破碎漏失,工程地质条件相对好,确定北通道为铁路通道;(3)预测停采后地表移动延续时间小于施工工期,提出了矿区停采、封井、路基沉降加宽等综合防治措施,施工期地面变形追踪监测显示,综合防治措施抑制地表变形效果显著;(4)采用泊松函数预测铁路最大工后沉降4.1 cm,满足通车条件,外绕线铁路于2020年8月正式通车运营;(5)本研究成果可为类似复杂采空区铁路选线与处理提供参考.
Research purposes:The salt mine with a depth of 500 m underground was mined by water solution method in Central-south China,and the deformation of the surface in the goaf area is serious.The outer line of the railway hub was designed to pass through the mining area with great engineering risks.Based on the measured deformation data of the surface,this paper studied the law of ground deformation induced by water mining,analyzed the risk of ground collapse with the dome of natural equilibrium and geophysical methods,determined a reasonable line channel,and proposed the comprehensive prevention measures for the railway crossing the deep buried water-soluble goaf.Research conclusions:(1)There were two subsidence centers with cumulative subsidence of 927 mm and 843 mm on the surface.The subsidence center was located on the ore pillar,and the goaf area had been connected.(2)The risk of the overlying rock collapsing to the ground was high in the south passage.However,only parts of the shafts in the north passage were broken and lost,and the engineering geological conditions were relatively good.And the north passage was selected as the final railway passage.(3)It was predicted that the duration of ground surface movement after the mining stop was shorter than the construction period,and comprehensive treatment measures such as mining stoppage,well closure,and roadbed subsidence widening in the mining area were proposed.The ground deformation tracking monitoring showed that the comprehensive treatment effect was excellent.(4)The maximum post-construction settlement of the line predicted by the Poisson function was 4.1 cm,which met the conditions for opening to traffic.The railway line was officially opened to traffic in August 2020.(5)The research results can provide reference for railway route selection and treatment in similar complex goafs.
作者
李卫东
LI Weidong(China Railway Wuhan Group Co.Ltd,Wuhan,Hubei 430071,China)
出处
《铁道工程学报》
EI
北大核心
2022年第12期17-23,共7页
Journal of Railway Engineering Society
