Optimization Model for Earth-Rock Allocation System in Large-Scale Hydraulic Engineering and Application in Shuibuya Project
Much importance is attached to the earth-rock allocation problem in the construction of many large-scale hydraulic engineering. Based on systemic view, the paper analyses the composition of the system and mutual relations among the elements. According to the analysis work, a linear programming model is constituted to optimize the operation of earth-rock allocation system to minimize the cost of the system. And the optimization model is put into operation in Shuibuya project in China. The calculating results by the model are economical and feasible in project construction
Linear programming model for finding optimal roadway grades that minimize earthwork cost
Abstract The cost of earthwork involved in road construction can vary widely based on the roadway grades chosen by the designer. There is almost an infinite number of feasible grades available to the designer to choose from, all of which satisfy the geometric specification of the road. For every feasible grade selected, a transportation problem must be solved, which is a very tedious task. The roadway grade selection is usually considered as a stage and the earthwork (transportation) is another stage. These two stages have always been treated separately in the literature. The model presented here combines the roadway grade selection stage and the earthwork transportation stage in a single linear programming problem, thus guaranteeing global optimality.
Earthwork Allocations with Linear Unit Costs
This paper presents a quadratic programming model of earthwork allocations that accommodates linear unit cost functions of purchase and excavation for borrow pits. The unit costs of haul and compaction for borrow pits and the various unit costs for earthwork from cut to fill sections and disposal sites are assumed to be constant (based on an earlier investigation). The solution of the model is explored and it is found that the global minimum cost is guaranteed only when the linear unit cost functions are nondecreasing. Extension of the model to accommodate setup costs for borrow pits and landfills is made and an efficient solution method is devised. This model, which complements existing optimization models of earthwork allocations, provides several capabilities over the commonly used mass‐haul diagram. Application of the model to a numerical example is presented.