scope:

Preface

This is the fourth edition of CSA A257 Series, Standards for Concrete Pipe and Manhole Sections. It supersedes the previous editions published in 1992, 1982, and 1974 under the title Standards for Concrete Pipe.

As with the previous editions, the Standards contained in this edition include requirements for C

• the determination of physical properties;
• non-reinforced circular concrete pipe;
• steel-reinforced circular concrete pipe; and
• joints for concrete pipe.

In 1992, CAN/CSA-A257.4, Precast Reinforced Circular Concrete Manhole Sections, Catch Basins, and Fittings, was added. It incorporated new test methods for flat slab tops and manhole steps and ladders. Major changes in this new edition include the following:

• revised hydrostatic test methods are included in A257.0, A257.1, and A257.2 to achieve consistency with Ontario Concrete Pipe Association (OCPA) pre-qualification practice;
• an Annex has been added to A257.4 to allow vacuum testing; and
• a clause on steel hoop circumferential reinforcement for manhole components has been added to A257.4 to help reduce the volume of reinforcing steel required in maintenance holes without compromising the stiffness requirement for handling.

These Standards were prepared by the Technical Committee on Concrete Pipe, under the jurisdiction of the Strategic Steering Committee on Concrete and Related Products, and have been formally approved by the Technical Committee. They will be submitted to the Standards Council of Canada for approval as National Standards of Canada.

Notes:

(1) Use of the singular does not exclude the plural (and vice versa) when the sense allows.

(2) Although the intended primary application of this Standard is stated in its Scope, it is important to note that it remains the responsibility of the users of the Standard to judge its suitability for their particular purpose.

(3) This publication was developed by consensus, which is defined by CSA Policy governing standardization - Code of good practice for standardization as "substantial agreement. Consensus implies much more than a simple majority, but not necessarily unanimity". It is consistent with this definition that a member may be included in the Technical Committee list and yet not be in full agreement with all clauses of this publication.

(4) CSA Standards are subject to periodic review, and suggestions for their improvement will be referred to the appropriate committee.

(5) All enquiries regarding this Standard, including requests for interpretation, should be addressed to Canadian Standards Association, 5060 Spectrum Way, Suite 100, Mississauga, Ontario, Canada L4W 5N6. Requests for interpretation should

(a) define the problem, making reference to the specific clause, and, where appropriate, include an illustrative sketch;

(b) provide an explanation of circumstances surrounding the actual field condition; and

(c) be phrased where possible to permit a specific "yes" or "no" answer.

Committee interpretations are processed in accordance with the CSA Directives and guidelines governing standardization and are published in CSA's periodical Info Update, which is available on the CSA Web site at www.csa.ca