Strain Distribution of Dowel-Type Connections Reinforced with Self-Tapping Screws
This article has been corrected.
VIEW CORRECTIONPublication: Journal of Materials in Civil Engineering
Volume 32, Issue 1
Abstract
Current limited guidance on the selection of screws together with undefined design specifications restricts the effectiveness of self-tapping screws as reinforcement on timber members to control crack propagation. Using digital image correlation (DIC), this study visualized the surface strain distribution of screw-reinforced dowel-type connections to understand the influence of thread configuration and screw-to-dowel distance on controlling crack propagation. The experiment was based on single-dowel embedment tests using 16- and 20-mm-diameter steel dowels. Three thread lengths (0%, 33%, and 100% thread) and six screw-to-dowel distances (, , , , , and ) were investigated. Results show that a screw with 33% thread on the point end can be as effective as screws with 100% thread to control crack propagation under the same geometrical parameters of the connections. Results also reveal that a screw placed further from the dowel (e.g., at distance) can delay the crack-controlling effect. Self-tapping screws placed at can still improve the embedment strength and ductility; however, further doubling this distance () did not enhance the embedment strength, but a higher ductility was still achieved.
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©2019 American Society of Civil Engineers.
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Received: Nov 1, 2018
Accepted: Apr 23, 2019
Published online: Oct 23, 2019
Published in print: Jan 1, 2020
Discussion open until: Mar 23, 2020
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