Multilevel Formwork Load Distribution with Posttensioned Slabs
Publication: Journal of Construction Engineering and Management
Volume 131, Issue 2
Abstract
Formwork and the associated shoring represent a significant proportion of the costs associated with the construction of multilevel concrete structures. To minimize these costs, a limited number of formwork and shoring sets are recycled up the structure as construction progresses, eliminating the need for a new set of formwork and shoring with each new slab. When a slab is posttensioned using draped tendons, slab lift occurs as a portion of the slab self-weight is balanced. The formwork and shores supporting that slab are unloaded by an amount equivalent to the load balanced by the posttensioning. This produces a load distribution through the structure that is inherently different from that of a conventionally reinforced slab. This paper presents two design methods suitable for modeling the multilevel formwork process for posttensioned slabs: A modification to the simplified analysis method and a finite element model—both techniques will be of immediate use by industry practitioners and of interest to researchers examining the load distribution phenomenon. The paper also summarizes the findings of one of only a few research projects in which actual shore loads were monitored during the construction of a multilevel posttensioned building, which is used to validate the proposed design models.
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References
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Information & Authors
Information
Published In
Journal of Construction Engineering and Management
Volume 131 • Issue 2 • February 2005
Pages: 203 - 210
Copyright
© 2005 ASCE.
History
Received: Mar 7, 2003
Accepted: Mar 17, 2004
Published online: Feb 1, 2005
Published in print: Feb 2005
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