中文摘要：

大型煤田进行露天开采时。通常采用分区开采，故必须考虑相邻采区间转向过渡的问题。分析了5种采区转向过渡方式，比较了各转向方式特点，结合蒙东能源西二号露天煤矿的实际生产现状，以矿山辅助设计软件SMCAD为平台进行三维地质建模、实体算量、模拟开采。引入垂直权高差概念。对比了4种连续式转向过渡方式的优劣，揭示了各转向方式条件下的剥采比、过渡时间、运距和总费用等变化规律，综合确定留沟直角转向为最优方案。

英文摘要：

A large coal field is usually divided into several mining areas in surface coal mine, therefore the steering transition problem between adjacent mining areas must be considered. This paper first analyzes five kinds of steering transition modes and compares the specific characteristics of these steering modes. Considering the actual production status of a surface mine, SMCAD, a computer-aided-design platform, is used for 3D geological modeling to study the mining. The advantages and disadvantages of four kinds of continuous steering transition modes are compared, and the variation of stripping ratio, transient time, load distance and total cost for each transition mode are revealed. Finally, a right angle turn left ditch optimal program is determined as the optimal scheme. This research achievement has a guiding significance for practical nroduction in surface coal mine.