Cross-laminated timber performs better than expected in shear test

The American Wood Council recently released the results of full-scale tests of cross-laminated timber (CLT) diaphragms.

The findings indicated that the connections performed better than expected, resulting in higher-than-expected shear capacities of the diaphragms.

“In order to fully understand the full-scale CLT diaphragm test results done last year, we needed to better understand some of the connections that were used in the full-scale tests,” said AWC Vice President of Engineering Bradford Douglas, P.E. “The results of these latest tests could lead to changes allowing more efficient CLT diaphragm designs in the future.”

The tests were conducted in support of new criteria for the CLT diaphragm design approach included in the 2021 Special Design Provisions for Wind and Seismic (SDPWS). The connection testing augments the full-scale diaphragm testing completed in 2020 and focuses on the structural performance of the individual connections of the diaphragm, designed in accordance with the National Design Specification for Wood Construction.

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