Minimizing Gable Roofing Materials in Proactive Design Phase by Using a Genetic Algorithm to Estimate the Purlin Spacings

Abstract

The purpose of this research was to apply a genetic algorithm to determine the spacing of gable roof purlins to minimize the roof tiles. In this research, drawings and detail specification of a 4-storey reinforced concrete building with a gable roof was used to develop a 3D model with the level of development (LOD) 350 using BIM Software. Then, determine the options of purlin spacing according to the engineering principles and requirements of material manufacturers. The parameters used to calculate the quantity of roof tiles are purlin spacing, king post height, width, and length of the roof. The heights of king post varied from 3.00-5.00 meters. Then a single-objective genetic algorithm was designed and used to optimize the quantity of corrugated tiles. It revealed that the quantity of roof tiles obtained from the genetic algorithm method was equal to the shop drawing, which was 3,310 tiles. It showed that the genetic algorithm method together with building information modeling (BIM) can be used to optimize purlin spacing well. Therefore, genetic algorithm is another alternative providing good results in construction process, which can be applied to minimize the construction materials or reduce the amount of wasting materials in response to the sustainable development.