Comparative study of bracing patterns and materials for tall timber buildings

Abstract

Exploration of new designs for urban environments is increasingly focusing on reducing carbon emissions generated by construction and operation of tall buildings. With recent technological advances in timber construction and its potential to mitigate the carbon embodied in structural materials, tall timber buildings are gaining acceptance as various forms are considered for their designs. Recently built and proposed buildings demonstrate the use of mass timber to resist gravity and lateral loads. There are inherent efficiencies in placing lateral load resisting systems on the perimeter of a structure along with the possibilities to integrate versatile geometric patterns and effective structural solutions. However, timber material properties may lead to elements of larger volume than those made of steel or concrete. This study compares structural stiffness gains and carbon emission reductions for exterior bracing created in timber and timber-steel hybrid configurations. Numerical analyses are used to explore braced frame geometries and layouts for the steel and timber elements, to predict structural response, and compare the effects of material placement.