954-1 Types of Timber and Treating Requirements.
Timber fence posts and braces shall be of southern yellow pine and shall be treated in accordance with Section 955. Prior to the treatment, all knots on the posts shall be trimmed close to the body of the post.
954-2 Requirements for Cutting.
Round or sawn posts will be permitted but all posts on a single project shall be the same. Sawn post shall comply with AASHTO M 168, have a minimum Fb of 1,350 psi, be grade- stamped by an inspection agency accredited by the American Lumber Standards Committee (ALSC), and shall meet the requirements of 954 -6. Round posts shall be cut from sound and solid trees and shall contain no unsound knots. The butt shall be cut at a sufficient distance above the ground swell of the tree that there will be no abrupt change in cross -section of the post. The butts shall be sawn square. The post tops shall be sawn neatly and at right angles to the vertical axis of the post.
954-3 Knots, etc.
Sound knots will be permitted provided the diameter of the knot does not exceed one- third of the diameter of the piece at the point where it occurs. Peck (in cypress posts) shall be limited as provided for knots; the area of permissible peck not exc eeding the area occupied by permissible knots, and a combination of peck and knots not exceeding the aggregate of knots allowed. The posts shall be free from decayed wood, rot, and red heart, and of ring shake or season checks which penetrate at any point more than one fourth the diameter of the piece, or are greater than 1/4 inch wide.
954-4 Peeling.
All posts shall be peeled for their full length, and all inner and outer bark removed, except that isolated strips of inner bark which do not exceed 1/2 inch in width or 3 inches in length will be permitted.
954-5 Straightness.
The straightness of the post shall be such that for any 8 foot post (or for any 8 feet of length, for longer posts) a straight line from the center of the tip to the center of the but t (or from center of the cross sections at the extremes of the 8 foot lengths) shall not fall outside the center of the mid -section of the 8 foot length by more than 2 inches.
954-6 Dimensions.
954-6.1 Minimum Lengths Allowable :
Line posts - 8 feet. Corner and pull posts - 8 feet, 6 inches. Braces - As required by the Plans. (A tolerance of minus 1 inch to plus 2 inches will be allowed in the lengths shown for the posts.) FY 2023-24 Return to Table of Contents
954-6.2 Minimum Allowable Cross Section:
Round line posts - 4 inch diamete r. Round braces, corner and pull posts - 5 inch diameter. Square line posts - 4 inches by 4 inches. Square braces, corner and pull posts - 5 inches by 5 inches. The minimum diameters specified for round posts are applicable before preservative trea tment. When the treated post is inspected at the job site a tolerance of 3/8 inch under such diameters will be allowed, to compensate for shrinkage resulting from treatment and storage. FY 2023-24 Return to Table of Contents SECTION 955 TIMBER TREATMENT (INCLUDING TREATING MATERIALS)
955-1 General.
The work specified in this Section is the treating of structural timber, timber piling and timber posts, bracing and railing. The method of treatment and determination of assay results for all such timber materials shall be in accordance with American Wood Protection Association (AWPA) Use Category System (UCS) - U1, with the exceptions and additions as specified herein. Use approved producers listed on the Department’s Production Facility Listing for timber components located in https://mac.fdot.gov/smoreports . Producers seeking inclusion shall meet the requirements of Section 105.
955-2 Preservative.
955-2.1 Guardrail Post, Fence Post, Bracing and Railing on Pedestrian Bridge s,
Buildings, and Rest Areas in Above Ground, Ground Contact, Fresh Water Immersion Applications (Pedestrian Use) : Provide guardrail post, fence post, bracing and railing in accordance with Table 955-1. Approved producers should provide a certification sho wing the treatment and assay results with every shipment. FY 2023-24 Return to Table of Contents