Corrugated Aluminum Alloy Structural Plate for Field-Bolted Pipe, Pipe-Arches, and Arches

B746/B746M: Standard Specification for Corrugated Aluminum Alloy Structural Plate for Field-Bolted Pipe, Pipe-Arches, and Arches

When designing and constructing essential infrastructure like culverts, storm sewers, and underpasses, engineers rely on authoritative standards to ensure the integrity and longevity of their projects. ASTM B746/B746M, the "Standard Specification for Corrugated Aluminum Alloy Structural Plate for Field-Bolted Pipe, Pipe-Arches, and Arches," is an industry-leading document that provides the foundational requirements for these vital components. This comprehensive standard ensures that the materials and fabrication of corrugated aluminum structural plates meet rigorous engineering demands for durability and performance in demanding civil engineering applications.

What is B746/B746M?

ASTM B746/B746M is the definitive standard for the materials and fabrication of corrugated aluminum alloy structural plates intended for field assembly into various drainage and underpass structures. Developed by ASTM International, this specification ensures that the structural plates, along with their associated fasteners, are manufactured to precise mechanical and dimensional standards for reliable performance in buried conduit applications. Its primary purpose is to provide engineers and specifiers with a trusted framework for selecting and utilizing these robust structural elements.

Scope & Purpose

This industry-leading standard governs the material composition, fabrication, and assembly requirements for corrugated aluminum alloy structural plates. It specifically covers their use in the construction of circular pipes, pipe-arches, and larger arch structures, as well as special shapes for field assembly. While the standard details requirements for the plates and fasteners, it explicitly excludes guidance on bedding, backfill, or the correlation between earth cover loads and plate thickness. These latter aspects are addressed in complementary practices to ensure a holistic approach to drainage structure design and installation.

Who Must Comply?

• • Primary audience: Civil Engineers, Structural Engineers, Project Managers, Construction Managers, and Materials Engineers involved in infrastructure design and construction.
• • Industries affected: Construction, Transportation, Public Works, Infrastructure Development, and Agricultural Drainage.
• • Compliance nature: Voluntary, but widely adopted and recommended for projects requiring proven performance and material integrity. Project specifications often mandate compliance.
• • Enforcement: Compliance is typically verified through material certifications, shop drawings, and inspection during fabrication and installation, often overseen by project engineers or owner representatives.

Key Requirements Overview

The standard requires that corrugated aluminum alloy flat plates are fabricated from specific aluminum alloys, such as 5052-H141, meeting defined tensile strength, yield strength, and elongation properties. Professionals must ensure that any extrusions used for stiffeners conform to approved aluminum alloy and temper designations. Key provisions include detailed specifications for assembly fasteners, outlining acceptable materials and configurations to ensure secure and durable connections between structural plates. The standard also emphasizes the importance of correlating plate thickness with site-specific corrosion and abrasion requirements, a crucial design consideration.

Related Standards & References

ASTM B746/B746M is an essential component of a broader suite of standards for buried drainage structures. It works in conjunction with ASTM B790/B790M (Practice for Structural Design of Corrugated Aluminum Pipe, Pipe-Arches, and Arches), which provides the engineering methodologies for calculating structural capacities. Furthermore, **ASTM B789