大型露天煤田安全高效集约化开发是露天煤炭开发的发展趋势，以分区开采为主要开发模式的大型露天煤田具有安全高效、回采率高、投资回收期短的显著优势，同时可以利用开采形成的采空区回填剥离物料形成内排土场，并降低剥离物料对土地的压占及破坏。针对大型露天煤矿分区开采衍生出相邻采区间二次剥离量大的问题，在考虑压帮内排留沟模式影响基础上，结合外排空间受限条件，以内排加高分析不同压帮留沟模式对剥采与运输系统的影响，建立全压帮及半压帮内排总费用模型，并对半压帮倒三角和倒梯形留沟模式进行对比分析。基于费用补偿法，以全压帮内排为参照，在剥离物料不外排的条件下，综合考虑内排容量，构建压帮内排倒三角留沟模式与倒梯形留沟模式的留沟高度优化模型以及内排搭桥移设步距优化模型。对山西河曲露天煤矿首采区与二采区间留沟高度及运输系统进行综合优化。结果表明：半压帮内排经济效益显著，压帮内排倒三角留沟总费用随着留沟高度的增加先增大后减小，总经济效益先减小后增大，最佳留沟高度为110 m，内排搭桥最佳移设步距为104 m，相对全压帮内排节约10080万元；压帮内排倒梯形留沟总费用随着留沟深度的增加先减小后增大，总收益先增大后减小，最佳留沟高度为67 m，内排搭桥最佳移设步距为264 m，相对全压帮内排节约24540万元。留沟面积相等的条件下，倒三角留沟模式留沟深度较大，对单侧剥离物料运输系统影响较大，内排土场工作线长度较长，一般适用于内排空间紧张的露天煤矿；倒梯形留沟模式留沟深度较小，内排容量受到一定限制，一般适用于内排空间较大的露天煤矿。

The development of large open-pit coal fields with high safety and efficiency is the trend of open-pit coal development. With partitioned mining as the main development mode, the large open-pit coal field has the significant advantages of safety and efficiency, high recovery rate and short investment payback period. At the same time, it is possible to use the backfilling of stripped materials in the mined area to form an inner dumping field and reduce the pressure and damage of stripped materials on the land. To address the problem of large surface coal mines with large secondary stripping volume between adjacent mining areas derived from partitioned mining, the impact of different remaining ditch mode for end-wall covered on stripping and transportation systems is analyzed by adding height to the inner dumping on the basis of considering the impact of inner dumping remaining ditch mode for end-wall covered, combined with the restricted space conditions for outer dumping. The total cost model of inner dumping with end-wall fully covered and inner dumping with end-wall semi-covered is established, and the inverted triangular and inverted trapezoidal retention ditch patterns of the end-wall semi-covered are compared and analyzed. Based on the expense compensation method, a model for optimizing the ditch height of the inverted triangular ditching mode and the inverted trapezoidal ditching mode, as well as a model for optimizing the distance of the internal ditching bridges, was constructed based on the cost-least method, taking the full internal ditching of the inner dumping covering as a reference, and taking into account the capacity of the internal ditching under the condition that the stripped material would not be discharged. The optimization of the ditch height and transportation system between the first and second mining areas of Hequ open-pit coal mine was carried out. The results show that: the economic benefits of half inner dumping covering are significant, the total cost of inverted triangular retention ditch increases and then decreases with the increase of the height of retention ditch, and the total economic benefit decreases and then increases. The best trench height is 110 m, and the best distance to move the inner row bridge is 104 m, which saves 100.8 million yuan relative to the inner dumping covering; the total cost of the inner dumping covering inverted trapezoidal retention ditch first decreases and then increases with the increase of the retention ditch depth, and the total benefit first increases and then decreases, the best retention ditch height is 67 m, and the best displacement step of the inner drainage hitch is 264 m, which saves 245.4 million yuan compared with the full inner dumping covering. Under the condition of equal retention ditch area, the inverted triangular retention ditch mode has a greater retention ditch depth, which has a greater impact on the single-side stripping material transportation system The long length of the working line of the inter row field is generally applicable to open coal mines with tight inter row space; the inverted trapezoidal retention ditch mode has a smaller retention ditch depth and the row capacity is somewhat restricted, which is generally applicable to open coal mines with larger inter row space.