摘要
为深入探究松散层段井壁破坏的机理,以东滩煤矿西风井为例,在其附近松散层内部进行工业性试验,并利用光纤光栅监测系统对地层应变变化情况进行检测;以挡土墙理论为依据,对井壁附加应力进行理论分析,并根据第四强度理论提出了井壁破坏的判据模型。抽水试验表明,抽水使得下组含水层水量减少,土层固结压缩,压应力增加,而中组松散层下沉滞后于下组松散层,造成中组松散层处于拉伸状态;补水试验表明,补水量每增加1000m3,松散层传感器的应变变化量平均增大1.61με,且随着水量的增加,下组松散层压应变明显减小,说明水量变化对地层影响显著;对井壁附加应力计算发现,含水层疏水会导致滑动线与水平面的夹角减小,从而导致土层锥体体积增大,附加应力增加。
In order to further study the failure mechanism of vertical shaft in loose strata,an industrial test was carried out in loose strata around west air shaft in Dongtan Coal Mine,the Fiber Bragg Grating system was used to monitor the change of strain in loose strata. The additional stress of shaft lining was calculated theoretically based on retaining wall theory and the criterion of shaft wall fracture model was built based on the fourth strength theory. Pumping water test showed that,water reduction led to consolidation of clayey and increment of compressive stress in lower coal group aquifer,it also led to clayey in a state of tension in middle coal group aquifer as movement of clayey in middle coal group aquifer lagged behind that in lower coal group aquifer. Supplying water test showed that,for each 1000m3 water increase,there was 1. 61μεincreased strain variation of the clayey,and with the increment of water,the compressive strain decreased obviously,indicating the clayey is heavily influenced by the change of flow. According to the calculation of the additional stress,the angel between slip line and horizontal plane decreases with the loss of aquifer,causing increment of soil centrum volume,and additional stress on shaft.
出处
《煤炭工程》
北大核心
2015年第11期87-89,93,共4页
Coal Engineering
基金
国家重点基础研究发展计划(973计划)资助项目(2013CB22790)
关键词
松散层
井壁
破坏机理
附加应力
立井井筒
loose strata
shaft lining
failure mechanism
additional stressp
vertical shaft
作者简介
许延春（1963-），男，河北乐亭人，博士，研究员，博导，现研究方向为特殊条件下安全采煤，E—mail：yanchun-xu@163．com。
