Design of concrete structures
The CSA A23.3:19 Standard and Redline bundle includes a copy of the active standard and the redline version in digital format. The redline document is designed to highlight changes from one edition to the next. It includes a full-text version of the new document, plus an indication of changes from the previous version.
This is the seventh edition of CSA A23.3, Design of concrete structures. It supersedes the previous editions published in 2014, 2004, 1994, 1984, 1977 (metric), and 1973 (imperial), and 1959.
This Standard is intended for use in the design of concrete structures for buildings in conjunction with CSA A23.1/A23.2, Concrete materials and methods of concrete construction/Methods of test and standard practices for concrete, and CSA A23.4, Precast concrete — Materials and construction.
Changes in this edition include the following:
• Some definitions have been updated.
• Additional information on cover for fire resistance has been provided in Clauses 7 and 8.
• Clause 10 on flexural ductility and slenderness effects has been updated.
• Clause 11 on the Simplified and General method for shear design has been updated.
• A new clause has been added to address punching shear around circular supports or reaction area.
• Clause 14 on walls has been updated.
• A new Clause 19 on structural diaphragms has been added. The previous Clause 19 on shells and folded plates has been moved to mandatory Annex E.
• Numerous updates have been added to Clause 21.
• Annex D is now a mandatory part of the Standard.
This Standard has been developed in compliance with Standards Council of Canada requirements for National Standards of Canada. It has been published as a National Standard of Canada by CSA Group.
This Standard specifies requirements, in accordance with the National Building Code of Canada, for the design and strength evaluation of
a) structures of reinforced and prestressed concrete; and
b) plain concrete elements.
1) For structures such as blast-resistant structures, tanks, reservoirs, swimming pools, bins, silos, towers, and chimneys, users of this Standard should also refer to applicable codes, standards, or guidelines for additional requirements.
2) Special requirements for parking structures are specified in CSA S413.
1.2 Fire resistance
This Standard requires designs to be carried out in accordance with the fire resistance requirements of the applicable building code (see Clause 8.1.2).
Note: Information on the fire resistance of concrete elements can be found in Appendix D of the National Building Code of Canada.
1.3 Alternative design procedures
Designs that use procedures that are not covered by this Standard but are carried out by a person qualified in the methods applied and provide a level of safety and performance equivalent to designs complying with this Standard are acceptable if carried out by one of the following methods:
a) analysis based on generally established theory;
b) evaluation of a full-scale structure or a prototype by a loading test; or
c) studies of model analogues.
1.4 Shells and folded plates
Design requirements for shells and folded plates can be found in Annex E.
In this Standard, shall is used to express a requirement, i.e., a provision that the user is obliged to satisfy in order to comply with the Standard; should is used to express a recommendation or that which is advised but not required; and may is used to express an option or that which is permissible within the limits of the Standard.
Notes accompanying clauses do not include requirements or alternative requirements; the purpose of a note accompanying a clause is to separate from the text explanatory or informative material.
Notes to tables and figures are considered part of the table or figure and may be written as requirements.
Annexes are designated normative (mandatory) or informative (non-mandatory) to define their application.
1.6 Units of measurement
Equations appearing in this Standard are compatible with the following units:
a) area: mm2 (square millimetres);
b) force: N (newtons);
c) length: mm (millimetres);
d) moment: N·mm (newton millimetres); and
e) stress: MPa (megapascals).
Whenever the square root of the concrete strength is determined, the concrete strength and the square root of the concrete strength are both expressed in megapascals.
Other dimensionally consistent combinations of units may be used, provided that appropriate adjustments are made to constants in non-homogeneous equations.
Note: Some examples of non-homogeneous equations are found in Clauses 12.2.2 and 12.8.