Coupling microscopic simulation and macroscopic optimization to improve earthwork construction processes

This paper presents a novel method for improving earthwork construction processes by coupling microscopic process simulation and macroscopic optimization approaches. It is designed as an iterative process where simulation and optimization procedures alternate with one another and exchange data with each other. The optimization module determines the optimal allocation of earthwork masses from cut to fill areas, in the first cycle with respect to distances and later in terms of haulage time. The generated output is used in the simulation module for routing the transport vehicles accordingly. Subsequently, the process time is determined in the simulation procedure by including diverse microscopic conditions. The resulting process time on each route is then used in the next optimization step as input for optimizing the earthwork allocations. The coupling cycle is repeated iteratively until the total earthwork process time converges. Initial tests based on input data of real high-way construction projects record a significant reduction in the total earthwork process time.