基于非均布载荷下梁结构破断理论的地表破坏规律

摘要

To study the mining damage regulations of the ground surface under the geological conditions of thick loess and thin bedrock in mountain areas,Hezhai coal mine,in the south of Shanxi province,is chosen as the study case. Based on the field investigations,the numerical simulation software of UDEC is employed to obtain the relationship between strata frac-ture and surface displacement. The numerical tests show that the most serious surface deformations happen upon the fracture positions of the rock strata. A fracture model of overlying strata is established as the beam structure under non-uniform load, from which the span equations of the primary fracture and periodic fractures are deduced. The comparison between the calculat-ed results and the locations of surface fissures measured by investigation shows the method developed in this study is available. The study shows that it is feasible to predict the surface crack spacing by using the non-uniform load beam structure fracture model under the condition of thin bedrock geological condition in the thick loess layer in the mountain area.%为研究晋南典型山区厚黄土层薄基岩地质条件下煤矿开采对地表的破坏规律,本研究以山西省河寨煤矿为例,在实地调查的基础上,采用UDEC软件进行数值模拟,得出岩层断裂及地表移动的关系.模拟得到上覆岩层断裂的位置,地表破坏最严重.根据模拟结果,建立了基于非均布载荷的梁结构覆岩破断模型,推导出覆岩初次断裂和周期断裂的步距公式.将计算结果与实测地表裂缝位置进行对比,取得较好的一致性.研究表明:在山区厚黄土层薄基岩地质条件下进行煤矿开采时,采用非均布载荷梁结构断裂模型预测地表裂缝间距是可行的.