American Wood Council: CLT passes full-scale diaphragm tests

CLT undergoing diaphram test

The American Wood Council (AWC) reports the successful completion of two full-scale cross-laminated timber (CLT) diaphragm tests to provide strength and deformation data important for evaluating CLT diaphragm resistance to lateral wind and earthquake forces. The tests were completed at Weyerhaeuser’s ISO 17025 accredited test facility in Federal Way, Washington.

“This research used full-scale seismic testing to test a CLT diaphragm supported by wood members, in this case glued laminated timber framing,” said AWC Vice President of Engineering Bradford Douglas, P.E. “The results showed the diaphragm performed well with diaphragm strength exceeding targets and load-deformation response primarily governed by connection behaviour. This testing used the CLT diaphragm design approach incorporated in the 2021 Special Design Provisions for Wind and Seismic which relies upon the design of wood members and connections in accordance with applicable requirements of the 2018 National Design Specification® for Wood Construction.”

The test results will also allow researchers to identify potential opportunities for optimisation to further advance use of this new versatile technology in floors and roofs of building structures.