冻结法成井井壁在深厚表土段附加应力研究  

Additional stress of shaft linings in thick alluvium constructed by freezing process

作　　者：孟志强[1,2] 纪洪广[1] 彭飞[1] 

机构地区：[1]北京科技大学金属矿山高效开采与安全教育部重点实验室,北京100083 [2]河北工程大学河北省资源勘探重点实验室,河北邯郸056038

出　　处：《煤炭学报》2013年第2期204-208,共5页Journal of China Coal Society

基　　金：国家高技术研究发展计划资助项目(2008AA062104);国家重点基础研究发展计划(973)资助项目(2010CB226803);国家科技支撑计划资助项目(2008BAB33B03)

摘　　要：为研究深厚表土段井壁的破坏机理,提高井筒的使用寿命,指导已破坏井筒维修和为新设计井筒提供依据,采用数值模拟和理论计算相结合的方法,对淮北煤田深厚表土段井壁附加应力的产生原因及大小进行了探讨。结果表明:附加应力由井壁和裹携土体重量产生,与地下水埋藏深度、土的容重、地下水层数有关,地下水埋藏越深,产生的附加应力越大,在基岩表面处的附加应力为89.91 MPa,远远超过了混凝土井壁的抗压强度。为避免井筒破坏,应采用方法是:增加井壁强度、保持原有水压、设法减少锥体的重量、井壁在应力集中处采用伸缩装置。To analyze the failure mechanism of shaft lining in thick alluvium and improve its service life, direct repara- tion for broken shaft lining, and provide evidence for new shaft lining design, this paper researched the reasons of shaft lining additional stress in Huaibei coalfield, combined numerical simulation and theoretical calculations. The results show that the additional stress is generated by weight of shaft finer and incidental conical soil, which is related to the groundwater depths, soil bulk density, and groundwater layer number. The deeper the groundwater is, the larger the ad- ditional stress is. The additional stress in bedrock surface reaches 89.91 MPa,which is far more than concrete com- pressive strength. In order to avoid shaft lining breakage, some measures are taken, for example, increasing shaft lining thickness, maintaining original hydraulic pressure, reducing the weight of incidental conical soil and using expansion device in stress concentration area.

关 键 词：深厚表土 附加应力 井壁破坏 冻结法 

分 类 号：TD265.3[矿业工程—矿井建设]