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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References
1.
“Building code requirements for reinforced concrete.” (1989). ACI 318‐89, American Concrete Institute (ACI), Detroit, Mich.
2.
Cohn, M. Z. (1965). “Rotation Compatibility in the limit design of reinforced concrete continuous beams.” Proc., Int. Symp. on Flexural Mechanics of Reinforced Concrete; ACI Special Publication 12, American Concrete Institute, Detroit, Mich., 359–381.
3.
Cohn, M. Z. (1967). “Limit design solutions for concrete structures.” J. Struct. Div., ASCE, 93(1), 37–58.
4.
Cohn, M. Z. (1968). “Limit design for reinforced concrete frames.” J. Struct. Div., ASCE, 94(10), 2467–2483.
5.
Cohn, M. Z. (1972a). “Equilibrium‐serviceability methods of limit design for reinforced concrete building structures.” Proc., ICE; Paper 7514S, Suppl. XIV, Institution of Civil Engineers (ICE), London, England, 263–275.
6.
Cohn, M. Z. (1972b). “Optimal limit design for reinforced concrete structures.” Proc. Int. Symp. on Inelasticity and Nonlinearity in Structural Concrete: SM Study No. 8, Paper 15, Univ. of Waterloo Press, Waterloo, Ontario, Canada, 357–388.
7.
Cohn, M. Z. (1979). “Inelasticity of reinforced concrete and structural standards.” J. Struct. Div., ASCE, 105(11), 2221–2241.
8.
Cohn, M. Z. (1988). “Non‐linearity of prestressed concrete and structural codes.” Proc. FIP Symp.—Israel '88, Fédération Internationale de la Précontrainte, London, England, 273–282.
9.
Cohn, M. Z., and Bartlett, M. (1982). “Nonlinear flexural response of partially prestressed concrete sections.” J. Struct. Div., ASCE, 108(12), 2747–2765.
10.
Cohn, M. Z., and Frostig, Y. (1983). “Inelastic behavior of PC beams.” J. Struct. Engrg., ASCE, 109(10), 2292–2309.
11.
Cohn, M. Z., and Ghosh, S. K. (1973). “Ductility of reinforced concrete sections.” IABSE Publications, Zurich, Switzerland, 32(2), 51–81.
12.
Cohn, M. Z., and Lounis, Z. (1991a). “Moment predistribution in Structural Concrete Codes,” Can. J. Civ. Engrs., 18(1), 97–108.
13.
Cohn, M. Z., and Lounis, Z. (1991b). “Serviceability control and nonlinear design of concrete structures.” Annales ITBTP, No. 493, 26‐53 (in French).
14.
Cohn, M. Z., and Riva, P. (1987). “A comprehensive study of the flexural behaviour of structural concrete elements.” Studi e Ricerche, Corso di Perfezionamento per le Costruzioni in Cemento Armato F.lli Pesenti, Politecnico di Milano, Vol. 9, 365–414.
15.
Cohn, M. Z., and Riva, P. (1989). “Equilibrium‐serviceability design of hyperstatic P.C. Beams,” Proc. Sessions Related to Design, Analysis and Testing at ASCE Structures Congress, ASCE, New York, N.Y., 201–212.
16.
Cohn, M. Z., and Riva, P. (1991). “Flexural ductility of structural concrete sections.” PCI J., 36(2), 72–87.
17.
“Design of Concrete Structures for Buildings.” (1984). CAN3‐A23.3‐M84, Canadian Standard Association (CSA), Rexdale, Ontario, Canada.
18.
“Eurocode no. 2: Design of concrete structures.” (1989). Commission of the European Communities, October.
19.
“Recommendations.” (1984). Practical design of reinforced and prestressed concrete structures, Thomas Telford Ltd., London, England.
20.
Lounis, Z. (1989). “Nonlinearity of structural concrete and codes of practice,” thesis, presented to the Univ. of Waterloo, at Waterloo, Ontario, Canada, in partial fulfillment of the requirements for the degree of Master of Applied Science.
21.
Model code for concrete structures. (1978). Comité Euro‐International in Beton (CEB) and Fédération Internationale de la Précontrainte (FIP), Paris, France.
22.
Riva, P. (1988). “Engineering approaches to nonlinear analysis of concrete structures, thesis presented to the Univ. of Waterloo, Waterloo, Ontario, Canada, in partial fulfillment of the requirements for the degree of Doctor of Philosophy.
23.
Riva, P., and Cohn, M. Z. (1989). “Some engineering applications of nonlinear analysis of concrete structures.” Studi e Ricerche, Corso di Perfezionamento per le Costruzioni in Cemento Armato F.lli Pesenti, Politecnico di Milano, Vol. 11, 225–267.
24.
Riva, P., and Cohn, M. Z. (1990). “Engineering approach to nonlinear analysis of concrete structures.” J. Struct. Engrg., ASCE, 116(8), 2162–2186.
25.
Sawyer, H. A., Jr. (1965). “Design of concrete frames for two failure stages.” Proc., Int. Symp. on Flexural Mechanics of Reinforced Concrete; ACI Special Publication, SP 12, American Concrete Institute (ACI), Detroit, Mich. 405–438.
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Copyright © 1992 ASCE.
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Published online: Feb 1, 1992
Published in print: Feb 1992
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