An evolutionary algorithm for solving the geometrically constrained site layout problem

Abstract

Construction site layout has been recognized as an important activity in construction site planning by field practitioners and researchers alike. This problem involves coordinating the use of limited space to accommodate temporary facilities (such as fabrication shops, trailers, materials or equipment) so that transportation costs of resources are minimized. The layout problem considered in this paper is a static layout problem characterized by affinity weights used to model transportation costs between facilities and by geometric constraints between relative positions of facilities on site. This paper presents an investigation of applying an evolutionary approach to optimally solve the aforementioned layout problem. The proposed algorithm is two-phases: an initialization phase that generates an initial population of layouts through a sequence of mutation operations, and a reproduction phase that evolve the layouts generated in phase one through a sequence of genetic operations aiming at finding an optimal layout. The paper concludes with a number of examples illustrating the strength and limitations of the proposed approach