Reliability-Based Load Requirements for Formwork Shores during Concrete Placement
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Volume 142, Issue 1
Abstract
One challenge in assessing the safety of concrete formwork supporting structures is the difficulty in predicting the loads on shores. Very limited studies on shore loads are available in the literature. This paper presents the results of a shore load investigation undertaken at three construction sites in Sydney. The study is focused on the vertical loads on shores during and following concrete placement. The statistical characteristics of the dead load effect and live load effect are determined. Structural reliability analyses are conducted to evaluate the reliability implications of the allowable stress design and limit state design approaches for shoring structures. An optimal load combination is derived considering the probabilistic characteristics of shore loads.
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Acknowledgments
This research is supported by Australian Research Council under Linkage Grant LP0884156. This support is gratefully acknowledged. The writers would like to thank Acro Formwork and Scaffolding for providing site access to procure the shore load survey data.
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Published In
Journal of Structural Engineering
Volume 142 • Issue 1 • January 2016
Copyright
© 2015 American Society of Civil Engineers.
History
Received: Aug 7, 2014
Accepted: Jun 2, 2015
Published online: Jul 6, 2015
Discussion open until: Dec 6, 2015
Published in print: Jan 1, 2016
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