SEISMIC RESPONSE EVALUATION OF FREEFORM LATTICE SHELL ROOFS WITH SUPPORTING SUBSTRUCTURES

Abstract

Seismic response of raised lattice shell roofs is known to be complicated due to the coupled vertical response when subjected to horizontal ground motions. The authors have proposed a simple response evaluation method for spherical domes and cylindrical shell roofs using amplification factors and equivalent static actions. However, it has only been verified for a limited number of shapes, which do not include the increasingly popular freeform roof topologies. In this paper, the previously proposed method is expanded to freeform structures generated with optimization methods and numeric form finding. The effect of parameters such as the roof shape, rise/span ratio, and supporting substructure on the seismic response is studied, and the simple evaluation method extended and verified for freeform shapes.