纵向充填采空区群人工充填体假顶稳定与强度匹配关系

Matching Relationship Between Stability and Strength of Artificial Filling Roof in Longitudinal Filling Goaf Group

为研究纵向充填采空区群假顶的稳定性与强度匹配关系,借助数值模拟与动力响应模型,从静力学与动力响应两个方面分析假顶稳定性。以某钨锡金属矿山多中段纵向充填采空区群为例,考虑顶板为原岩,灰砂比为1∶2,1∶4与1∶6的充填体,对充填体假顶稳定性进行了分析。研究结果表明:在开挖前这一工况时,顶板为原岩,不同强度充填体顶板均处于稳定状态,随着顶板强度变小,其挠度值迅速增加;在开挖这一工况时,原岩、灰砂比1∶2与1∶4的充填体顶板处于稳定状态,灰砂比1∶6的充填体顶板处于临界稳定状态;在开挖后这一工况时,原岩、灰砂比1∶2的充填体顶板处于稳定状态,灰砂比1∶4的充填体顶板处于临界稳定状态,灰砂比1∶6的充填体顶板处于失稳状态。工程实践表明:矿山采用灰砂比1∶4的充填体顶板并适当加固的条件下,回采下中段矿体时,顶板处于稳定状态。研究成果为纵向充填采空区群假顶稳定性分析及强度匹配提供了一个新的参考依据。

In order to study the matching relationship between the stability and the strength of the artificial roof in the longitudinal filling goaf group,with the help of numerical simulation and dynamic response model,the stability of the artificial roof was analyzed from two aspects of statics and dynamic response.Taking the multi-stage longitudinal filling goaf group in a tungsten tin metal mine as an example,considering the roof as the original rock,the stability of the filling roof was analyzed under the cement-sand ratio of 1:2,1:4 and 1:6.The results were concluded as follows.Firstly,before excavation,the roof was the original rock,and the roofs with different strength filling bodies were in a stable state.As the strength of the roof became smaller,the deflection value increased rapidly.Secondly,during excavation,the roof was in a stable state under original rock or the filling bodies with cement-sand ratio of 1:2 and 1:4,and was in a critical stable state under the cementsand ratio of 1:6.Thirdly,after excavation,the roof was in a stable state,critical stable state,and unstable state,under the filling body with cement-sand ratios of 1:2,1:4,and 1:6 respectively.Engineering practice showed that,when the lowerstage ore body was mined,the roof was stable under the filling body roof with cement-sand ratio of 1:4 and applying proper reinforcement.The research results could provide a new reference for the matching relationship between stability analysis and strength of the artificial roof in the longitudinal filling goaf group.