Yield Safety, Cracking Control, and Moment Redistribution
Publication: Journal of Structural Engineering
Volume 118, Issue 2
Abstract
Yield safety is introduced as a variable that controls both the cracking under service conditions and the permissible redistribution of ductile structural concrete frameworks at the ultimate limit state. Limiting values of the yield safety that ensure satisfaction of the code‐specified cracking criteria are derived from the results of a comprehensive computer investigation. A parametric study of the yield‐safety factor against cracking identifies the reinforcing index, ω, the allowable crack width, (or concrete tensile strength ), and the degree of prestressing, γ, as the governing factors in cracking control. These factors, along with the live‐to‐total service load ratio, which affects the overall safety of the structure, determine the permissible moment redistribution of concrete frameworks. Numerical examples of design (with concurrent satisfaction of the ultimate and serviceability limit states) and analysis of cracking serviceability criteria, in agreement with ACI 318‐89 code requirements, illustrate the application of the concepts presented.
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Information & Authors
Information
Published In
Journal of Structural Engineering
Volume 118 • Issue 2 • February 1992
Pages: 447 - 468
Copyright
Copyright © 1992 ASCE.
History
Published online: Feb 1, 1992
Published in print: Feb 1992
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