挖方和填方的最小运输问题
摘要
挖方和填方的最小运输问题求解其实是1个土方平衡调配问题。土方平衡调配是土方规划设计的1项重要内容。它主要是对土方工程中挖方的土需运至何处（利用或堆弃），填方所需的土应取自何方，进行综合协调处理。其目的是在使土方运输量或土方运输成本最低的条件下，确定挖、填方区土方的调配方向和数量，从而缩短工期，提高经济效益。
以数学模型为基础的竖向设计中土方调运,论述的是在土方调运过程中运用表上作业法的常用3个方法：西北角法、最小元素法和沃格尔法(VOGEL),以及用位势法判断基可行解是否最优，如不是对其再进行优化的详细过程,并对其做了简单的实例对比计算，然后再结合实际情况，考虑土方的松散状况，通过引进涨方系数，最后提出在实际工程应力计算中选择既计算简单又省时省力的的最小元素法和位势法的结合应用。
关键词：竖向设计；土方调运；最优方案；VOGEL法
Abstract
Solving the smallest transportation question of excavation and fill actually is a question of earthwork balance adjustment. The earthwork balance adjustment is an important part of earthwork planning and design, which mainly comprehensively handle where the soil of excavation shall transport to and where the soil needed by fill shall take from. Its purpose is to determine the adjustment way and quantity of the earthwork of excavation and fill to ensure the minimum earthwork transportation quantity and cost, and then shorten the work period and improve economic efficiency.
The earthwork transportation in the vertical design on the basis of mathematical model explains three normal methods in the process of earthwork transportation: Northwest corner method, smallest element method and VOGEL method. It also elaborates if judgment by geopotential method is the best, if not, then optimizes it. After comparing with actual example, considering the loose condition of earthwork and introducing the ratio zh, it is suggested to combine smallest element method and geopotential method which is simple and can save time and labor, into calculation of actual project.
Key words: Vertical design; earthwork transportation; optimal plan; VOGEL method
