Structural topology optimisation of long-span structures (Helping architects weigh their options)

The power of the approach proposed in this research project can be exercised performing a series of studies focusing on long-span buildings and structures such as roofs for archaeological sites, airport terminals, concert halls, and bus stations. Such structural forms pose a special modelling challenge: they often have large open spaces with unusual shapes and few interior columns, so they rely on systems of triangular space trusses and frames working together to support the load of the building. The use of computer simulation early in the design process - when the share of the building in determined - can have a major impact on embodied energy as well. Careful choice of the geometry and layout of the structure can reduce internal forces and decrease the amount of energy-intensive structural materials required for support.

This study will attempt to find an efficient scheme for the optimisation of both shape and member stiffness distributions in order to create a spatial structure with a higher buckling strength that then one created by just the shape optimisation and free-form finding processes. The geometric characteristics will be optimised for a target to maximise their linear buckling load for a vertical uniformly distributed load or a static seismic load. The buckling behaviour of the optimum reticulated shells will be also examined through elastic and elasto-plastic buckling analyses. Structural topology (material) optimisation studies will be performed using Altair's Hyperworks and static/dynamic analyses will be performed using the nonlinear Finite Element programme (ANSYS). Both the initial energy required for making structural materials and components as well as the future operational energy will be quantified and compared for the design of energy-efficient buildings.