W = 500(LN/(N - 1) + 12N + 36)
where W equals overall gross weight on any group of two or more consecutive axles to the nearest five hundred pounds, L equals distance in feet between the extreme of any group of two or more consecutive axles, and N equals number of axles in group under consideration, except that two consecutive sets of tandem axles may carry a gross load of thirty-four thousand pounds each provided the overall distance between the first and last axles of the consecutive sets of tandem axles is thirty-six feet or more. The overall gross weight shall not exceed eighty thousand pounds, including all enforcement tolerances, except for those vehicles and loads which cannot be easily dismantled or divided and which have been issued special permits.
Vehicles with Type Two axle configuration (three axle combination with one single axle and one set of tandem axles); or Type Six axle configuration (five axle combination with one single axle and two sets of tandem axles); or a vehicle with Type Eight axle configuration (six axle combination with one single axle, one tandem axle, and one tridem axle); or vehicles with Type Ten axle configuration (double bottom); or Type Eighteen axle configuration (four axle combination with one single axle and one set of tridem axles) carrying any of the following bulk commodities thereof: forest products in their natural state, lumber, sand, gravel, agricultural products in their natural state, loose or mixed concrete (including asphaltic or Portland cement), or bulk liquid commodities.
La. R.S. § 32:386
SEE ACTS 1987, NO. 686, §2 FOR RULEMAKING AUTHORITY.