协同理念下岩金矿脉群连续回采顶板安全跨度研究

为高效安全地开采呈条带状赋存的矿脉群,基于协同开采理念,提出集群连续化采矿理念与上向水平分层充填连续采矿法,并通过理论计算、数值模拟和工程验证,研究回采中顶板安全跨度的合理取值范围。采用平板梁理论计算法、普氏压力拱法、厚跨比法、荷载传递交汇线法和结构力学梁理论法推导得出顶板安全跨度计算公式,并引入安全系数,计算得出不同安全系数下的顶板跨度。经协同均算法界定分析,确定集群连续采矿方法的顶板安全跨度范围为23.0~18.6 m。结合理论计算的顶板跨度数据,取安全系数为2.0时的顶板跨度,采用ANSYS进行实体建模,基于FLAC3D进行数值模拟验证。模拟结果表明:最大主应力为2.84 MPa,最大位移为9.7 mm,矿房中央位置存在小范围剪切应力破坏;工程实例表明:当采场跨度为18 m时,采场顶板局部小范围存在岩块掉落情况,掉落岩块长度与顶板跨度之比为1.67%,数值模拟结果与工程实例情况接近。协同开采理念具有较强的耦合性与包容性,其耦合形成的新理念为多种复杂的矿体开采起到指导作用,能够较好地满足复杂矿体矿山开采要求。

Research on Safety Roof Span in Continuous Mining of Gold Vein Group Under Synergistic Concept

In order to mine strip cluster veins efficiently and safely,based on the concept of collaborative mining,the concept of cluster continuous mining and the continuous horizontal layered filling continuous mining method were proposed.First and foremost,the theoretical calculation methods of slab beam,Platts pressure arch method,thick-span ratio method,load transfer intersection line method and structural mechanics beam theory method were used,and the safety factor was introduced to calculate the roof span under different safety factors.The roof safety problem of the continuous mining method is studied.Furthermore,through the analysis,the safe stoping span of cluster continuous mining method is ranged from 23.0 m to 18.6 m.When the safety factor was 2.0,the number of roof span was modeled by ANSYS and verified by Flac3D.For one thing,the numerical simulation results show that the maximum principal stress is 2.84 MPa,and the maximum displacement is 9.7 mm.There is only a small shear stress failure in the middle chamber.For another,the engineering example shows that:when the stope span is 18 m(rounding 18.6 m),there is rock block falling in a small local area of the roof,and the ratio of the length of the falling block to the roof span is 1.67%.The numerical simulation and engineering example results are alike.Finally,the concept of collaborative mining has strong coupling and inclusiveness.Besides,the new concept plays a guiding role for mining complex ore bodies in China,which can better meet the mining requirements.