Wind Uplift Strength Capacity Variation in Roof-to-Wall Connections of Timber-Framed Houses
Publication: Journal of Architectural Engineering
Volume 22, Issue 2
Abstract
The roof-to-wall connection in a house is designed to transfer the uplift and lateral loads during strong winds by providing a continuous load path from the roof to the foundation. The uplift capacity and failure mode of the connection depends on the number and type of fasteners (nails), timber species, type of framing anchor, and constructions defects. This paper presents experimental results that were used to assess the uplift capacity variation of typical roof-to-wall connections. Based on tests with two types of connections (triple grip and truss grip) assembled with two types of timber (radiata pine and spruce pine), nails (hand and gun), and framing anchors (triple grip and universal triple grip), the results show that the variation in timber species, nail, and triple grip type changes the strength and the failure modes of the connection. The strength of the connection was reduced by about 24% when the timber species was changed from radiata pine to spruce pine and the hand nail to gun nail on the triple grip connection. This study also showed that construction defects in roof-to-wall connections influence the design uplift capacity. If there are two missing nails in the hand-nailed triple grip connection (i.e., one nail on the truss and another one on the top plate) the design uplift capacity reduces by about 40% of the ideal hand-nailed triple grip connection. This study identified the critical nails and their locations required to mitigate failure of the roof-to-wall triple grip connection subject to wind loading.
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Acknowledgments
This study is part of the research conducted by Climate Adaptation Engineering for Extreme Events Cluster funded by CSIRO Land and Water. The authors gratefully acknowledge the funding support of CSIRO and the support of the technical staff of Structural Laboratory and of Cyclone Testing Station, James Cook University, Townsville, Australia.
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Information & Authors
Information
Published In
Journal of Architectural Engineering
Volume 22 • Issue 2 • June 2016
Copyright
© 2016 American Society of Civil Engineers.
History
Received: Feb 20, 2015
Accepted: Nov 5, 2015
Published online: Feb 10, 2016
Published in print: Jun 1, 2016
Discussion open until: Jul 10, 2016
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