穰家垅银矿存在大量采空区和尾砂堆积等问题，矿山采用的空场法已不能满足持续发展的需求。为提高采场作业安全性，缓解地表尾砂排放压力，拟采用二步骤空场嗣后充填法进行回采，以期处理地表堆积的尾砂，保证采场安全稳定，为此亟待确定采场结构参数。研究建立了5种不同跨度的采场结构模型，利用有限元仿真模拟软件分析二步回采后顶柱、充填体人工矿柱的应力及位移，综合对比不同方案下的顶柱和充填体间柱的安全性，得出采场跨度为15~25 m时，采场安全稳定。考虑到矿山经济效益，最终确定合理的采场跨度为20~25 m。这对同类工程地质条件下的矿山开采具有借鉴意义。

Rangjialong mine is a continuous mining mine，and a large number of mined-out areas are left over from years of open-field mining，which are prone to caving and collapse，thus inducing large-scale ground pressure activities.A large number of pillars are left in the open field method，and the loss of pillar resources is serious.At the same time，tailings pond design dam crest elevation of 165 m，the current has been discharged to 156 m，tailings pond storage capacity is close to saturation，the mine is facing the dilemma of nowhere to discharge the tailings.In order to solve the above problems，the mine will change the current method to the two-step stope backfilling method，which is urgent to determine the safe and reasonable stope structure parameters，mainly considering stope span.In this study，finite element simulation software was used to establish 5 stope structure models with different spans，with a gradient of 5 m and a span range of 15~35 m.The two-step stoping process is simulated，and the stress distribution and displacement variation of the two step stoping pillar and backfill artificial pillar were obtained，and the ultimate strength of the stope rock (or backfill) was compared，and the stope structure parameters were optimized.According to the results of simulation，the value of the tensile stress of the artificial pillar and backfill in each scheme is less than the allowable tensile stress，the safety coefficient of the tensile stress decreases with the increase of the stope width，and the minimum value is close to 2.0.The roof column and pillar under each simulation scheme are not in a state of instability.When the stope span is between 15 m and 25 m，the simulated compressive stress value of the corresponding model is in the critical state or stable state，the compressive stress safety coefficient is greater than 1.3，and the Y direction displacement is uniform.The simulated compressive stress value of the roof pillar is very close to the allowable value when the stope span is greater than 30 m，the roof column is prone to compressive stress failure.The overall displacement change in the Y direction of the filling artificial pillar under 5 schemes does not exceed 10 mm，which is safe and controllable.In order to ensure the economic benefits of the mine，the reasonable stope span is finally determined to be 20~25 m，the stope width is 40 m and the stage height is 80 m.It can provide theoretical support for the recovery of residual ore resources in mines with similar engineering geological conditions.