Engineering design of optimized reinforced concrete floor grillages

Abstract

A new reinforced concrete beam grillage floor system is proposed as a lightweight alternative to traditional solid flat or waffle slabs used in construction. For the first time, beam grillage optimization has been paired with design code compliant floor plate design, for single and multi-bays of a building. The investigated floor slabs are novel, in that the depths of the grillage T-beams and their reinforcement are tailored for the local strength demands. This engineering efficiency gives rise to significant savings of approximately 40–50% in the quantities of concrete and steel needed compared to flat slabs. For the multi-bay studies, it was found that moving the location of the supporting columns could further decrease the volume of material required, by over 50% compared to a standard grid layout. Given the urgent need to reduce the volume of material consumed in construction projects, this appears to challenge traditional floorplate layouts. The research shows that digital optimization tools can be paired with standard design code rules to deliver significantly more sustainable building designs, though these benefits need to be balanced against the construction challenges associated with the more complex geometries that generally result.