Section 716 — Material for Timber Structures

716.01Untreated Structural Timber and Lumber. Conform to AASHTO M 168. Provide an inspection certification from an agency accredited by the American Lumber Standards Committee for the species and grade. Mark pieces with the inspection service, grade designation, species, and inspector identity. Season and dry structural timber and lumber before fabrication. Do not use material that is twisted, curved, or otherwise distorted. Do not use boxed- heart pieces of Douglas fir or redwood in outside stringers, floor beams, caps, posts, sills, or rail posts.

716.02Treated Structural Timber and Lumber. Provide wood according to Subsection 716.01, treated according to AASHTO M 133 and AWPA Standards U1 and T1. Provide t reated timber members with a quality mark approved by the American Lumber Standards Committee or equivalent for individual pieces or sealed pallets assuring that treatment conforms to the appropriate AWPA standards. For hand- contact surfaces such as handrails, use timber treated with waterborne co pper- based solutions or suspensions containing copper that do not contain arsenic or chromium compounds.

716.03Structural Glued Laminated Timber. Conform to ANSI A190.1, Product Standard for Structural Glued Laminated Timber and ANSI 117, Standard Specif ications for Structural Glued Laminated Timber of Softwood Species. Provide members with industrial appearance grade for wet use conditions. Use only single -piece or multiple -piece laminations with bonded edge joints. Provide s traight or slightly cambered members which are to be loaded perpendicular to the wide face of the laminates that are stamped top on the top at both ends of the beam.

716.04Wood -Plastic Composite . Provide composite timber decking that can support commercial use with the stringer spacing as shown in the plans. Provide boards with a flat, non- grooved texture at the bottom face. Conform to ASTM D7568 and the following:

(a)Ultimate bending strength, ASTM D198 2500 psi minimum

(b)Ultimate modulus of rupture, ASTM D7031 2500 psi minimum

(c)Ultimate modulus of elasticity, ASTM D 7031 200,000 psi minimum

(d)Fungus resistance, ASTM D1413 No decay

716.05Hardware. Provide bolts, drift pins, and dowels conforming to ASTM A307. Provide nuts conforming to ASTM A563. Provide gray iron castings according to Subsection 717.04(c) , and malleable iron castings according to Subsection 717.04(d) . 839 Provide nails and spikes conforming to ASTM F1667. Galvanize iron and steel hardware according to ASTM A153.