西部侏罗系深基岩立井井壁冻结压力实测与分析

摘要

为掌握西部侏罗系地层深厚含水基岩段井筒外壁荷载 ,采用振弦式传感器 ,对新街矿区红庆河煤矿二号风井基岩冻结压力进行现场实测分析,得到外层井壁冻结压力变化规律.研究表明:冻结压力发展趋势表现出阶段性特征 ,即在混凝土井壁浇筑后的12 d内,急速增大 ,达1. 286~1. 371 M Pa ,为最终稳定值的70% ~88% ;随后缓慢增长、降低并趋于稳定.受多种因素及原位测试影响 ,冻结压力在同一层位 ,呈现出非均匀分布的特点.侏罗系软岩地层实测冻结压力最大值为1. 872 M Pa ,远小于中东部冲积层冻结压力上限值 ,也小于西部基岩段冻结压力最高经验值 ,为保证冻结凿井施工安全提供了依据.%To master the load of outer shaft lining in western jurassic deep aqueous bedrock ,by using the vibrating wire sensors to measure and analyze bedrock's freezing pressure of Hongqinghe Coal Mine No.2 Air Shaft in Xinjie Mining Area ,freezing pressure variation of outer shaft lining was ob-tained. The results show that the development tendency of freezing pressure had stage features ,a freezing pressure was seriously increased within 12 d after concrete pouring ,reached at 1.286~1.371 M Pa and w hich is 70% ~88% of the final steady-state value ,then slow grow th and decline ,gradual steadiness eventually ;the freezing pressure had inhomogeneity at the same level ,w hich caused by in-situ test and many factors ;the measured maximum value of freezing pressure in jurassic stratum is 1.872 MPa ,which is far less than the upper limit value in eastern epipedon and the maximal empirical value of w estern bedrock.