Innovative timber structures : a proposal for a curved plywood box beam structural system

Abstract

I have an interest in innovative timber structures in architectural and free form situations. Research by design was aimed at discovering how to economise on the structural use of plywood in a free form curved plywood box beam system. Literature relevant to the question could not be found on this type of plywood box beam structure, therefore doubly curved timber structures are compared to it. The computer is used as a research tool to understand the geometric constraints of the structure and obtain an aesthetic chord width based upon the scale of the space. Two assumptions were made in calculations on an idealised box beam at different scales:- There would be a reduction in section sizes of the members, due to the reduced uniformly distributed load (UDL). There would be greater resistance to buckling of the webs of the box beam due to continuous lateral support from both sides. It is found that the reduction in member sizes was more than anticipated and that economy of structure and plywood can be achieved for any shape the structure follows. The outcome of the research is a set of prescriptive rules for using the curved plywood box beam structure in architecture.