This specification covers open- and closed-face precast reinforced concrete crib wall members for earth-retaining structures or protection against stream encroachment. The concrete crib wall shall conform to the dimensions prescribed in this specification. Manufacturing materials shall include portland cement, aggregates, chemical admixtures, water, and steel reinforcement. Manufacturing shall conform to the procedures which include mixing, reinforcement-concrete placing, forming, curing, cleaning, oiling, and finishing. Compression tests shall be made on standard concrete cylinders and shall conform to the design strength indicated in this specification.

1.1 This specification covers open- and closed-face precast reinforced concrete crib walls intended to act as earth-retaining structures or as protection against stream encroachment.

Note 1: This specification is a manufacturing and purchase specification only, with examples and suggestions for usage. Successful performance of this product depends on the proper selection and assembling of members, proper foundation and bearing material, and consideration of backfill heights, backfill material, drainage, and other engineering and construction considerations. The purchaser of the crib wall members specified herein is cautioned that he must properly correlate the field requirements with the members selected and provide adequate inspection at the construction site.

1.2 The values stated in inch-pound units are to be regarded as the standard. The values given in parentheses are for information only.

1.3 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.