營建工程中,土石方之運送方式係以傾卸卡車為主,如何以快速有效並節省成本的方法調派土石方及車輛資源,實為土石方業者獲利之關鍵。本研究以系統最佳化的觀點,針對土石方調派作業以及傾卸卡車派遣規劃問題發展適合之模式,以提供決策者一輔助工具,有效地規劃其排程。本研究利用時空網路流動技巧以定式傾卸卡車及其所載運之土石方在時空中的流動狀況,並根據問題特性加入額外限制,以期符合實務營運條件,之後利用數學規劃方法構建模式,而模式屬於含額外限制之整數網路流動問題。為適當地評估模式之實用績效,本研究以臺灣一大型營建工程之營運資料為範例進行測試與分析,結果顯示模式之排程規劃效果甚佳,且問題可在合理時間內求解。
In construction projects, dump trucks are usually used to transport earth materials from a location to another. An efficient plan of earthmoving and dump truck dispatching is essential for the profitability of a project. In this research we develop a model to plan the earthmoving operation and dump truck dispatching simultaneously from a system optimization perspective. The model is expected to serve as a planning tool for construction contractors to design the optimal schedules for moving earth materials and dispatching trucks. To develop the mathematical model, we employ time-space network flow techniques to formulate the dump truck flows and earth material flows in the dimensions of time and space, coupled with suitable side constraints to comply with real operating requirements. The model is formulated as an integer network flow problem with side constraints. To suitably evaluate the model, we perform a case study using real operating data from a large construction project in Taiwan. The test results show that the model is effective and the problem can be solved within a reasonable time.