热力隧道在非降水施工中的力学特性监测

城市热力供水工程逐渐由近地层明挖向深地层暗挖转移,通过对北京市两个典型地质热力隧道的现场原位的监测,分析浅埋暗挖热力隧道在非降水施工过程中对于砂卵石地质和粉质黏土地质条件下的初支结构内力、围岩性状、水文特征的变化及对地层的影响.试验监测结果表明,隧道围岩的土压力分布不同,水压力分布相同,初衬钢筋内力分布不同,砂卵石地质条件下的隧道初衬受力情况较好,隧道开挖对地表沉降影响较小,研究结果可在开挖城市供热、供水及供气等小断面隧道时参考.

Analysis of mechanical behavior monitoring test of thermal tunnel with non-dewatering construction

More and more urban thermal water supply project comes from the deep depth excavation gradually,rather than the cut and cover shallow buries.The insitu monitoring tests of Beijing two typical geology thermal tunnels are carried out.Then this paper analyzed the internal stress characteristics of supported structure lining,the surrounding rock mechanics characters,the hydraulic characteristics,and the ground surface settlement influence in sand-pebbles geological and silty-clay geological conditions with non-dewatering construction process.The research monitoring results show that the surrounding rock pressure distribution is different under various geological conditions,but the water pressure distribution is similar under different geological conditions,and the lining steel internal forces distribution is also different.The lining stress situation in the sand-pebbles geological condition is preferable to that in the silty clay soil condition.Tunnel excavation has less impact on the ground surface settlement.The research results can be applied to small section urban tunnels for thermal supply,water supply and gas supply.