(a) The maximum axle load shall not exceed the number of pounds designated in the following provisions which prescribe the distance between axles:
(1) When the axle spacing is nine feet or more between axles, the maximum axle load shall not exceed 18,000 pounds for vehicles equipped with high pressure pneumatic or balloon tires.
(2) When the axle spacing is less than nine feet between two axles but more than three and one-half feet, the maximum axle load shall not exceed 13,000 pounds for high pressure pneumatic or balloon tires.
(3) When axles are spaced less than three and one-half feet apart, the maximum axle load shall not exceed 9,000 pounds per axle.
(4) Paragraphs (a)(1) to (3) hereof shall be known as the normal loading maximum.
(b) When normal loading is in effect, the State Transportation Department and local authorities with respect to highways under their jurisdiction may designate certain highways, or sections of those highways, where bridges and road surfaces are adequate for heavier loading, which designation may be revised as needed, on which the maximum tandem axle assembly loading shall not exceed 16,000 pounds for any axle of the assembly, if there is no other axle within nine feet of any axle of the assembly.
(c) Except as provided in subsection (h) hereof, on a legal combination of vehicles, only one tandem axle assembly shall be permitted on the designated highways at the gross permissible weight of 16,000 pounds per axle, if there is no other axle within nine feet of any axle of the assembly, and if no other tandem axle assembly in the combination of vehicles exceeds a gross weight of 13,000 pounds per axle. When the maximum gross weight of a combination of vehicles with load does not exceed 73,280 pounds, two tandem axle assemblies shall be permitted on the designated highways at a gross permissible weight of 16,000 pounds per axle, if there is no other axle within nine feet of any axle of the assembly.
(d) The normal size of tires shall be the rated size as published by the manufacturers, and the maximum wheel load permissible for any wheel shall not exceed 700 pounds per inch of width of tire.
(e) During the months of March, April, and May in each year, the maximum axle load allowable on concrete pavements, or pavements with a concrete base, shall be reduced by twenty-five percent from the maximum axle load as specified in this chapter, and the maximum axle loads allowable on all other types of roads during these months shall be reduced by thirty-five percent from the maximum axle loads as specified. The maximum wheel load shall not exceed 525 pounds per inch of tire width on concrete and concrete base or 450 pounds per inch of tire width on all other roads during the period the seasonal road restrictions are in effect. Upon receipt of a written application and good cause being shown, the City, for roads under its jurisdiction, the State Transportation Department, for roads under its jurisdiction, and County Road Commissions, for roads under their jurisdiction, may permit exemptions from seasonal weight restrictions for milk on specified routes when requested. Approval or denial of a request for an exemption shall be given by written notice to the applicant within thirty days after the date of submission of the application. If a request is denied, the written notice shall state the reason for denial and alternate routes for which the permit may be issued. The applicant shall have the right to appeal to the State Transportation Department or the County Road Commission. These exemptions shall not apply on county roads in counties which have negotiated agreements with milk haulers, or haulers of other commodities, during periods of seasonal load limits in years prior to the effective date of this 1993 amendatory act. This 1993 amendatory act shall not limit the ability of these counties to continue to negotiate such agreements.
(f) The State Transportation Department, or a local authority with respect to highways under its jurisdiction, may suspend the restrictions imposed by this section when and where, in its discretion, conditions of the highways or the public health, safety, and welfare so warrant, and may impose the restricted loading requirements of this section on designated highways at any other time that the conditions of the highway may require.
(g) For the purpose of enforcement of the Act, the gross vehicle weight of a single vehicle and load or a combination of vehicles and loads, shall be determined by weighing individual axles or groups of axles, and the total weight on all the axles shall be the gross vehicle weight. In addition, the gross axle weight shall be determined by weighing individual axles or by weighing a group of axles and dividing the gross weight of the group of axles by the number of axles in the group. Pursuant to subsection (h) hereof, the overall gross weight on a group of two or more axles shall be determined by weighing individual axles or several axles, and the total weight of all the axles in the group shall be the overall gross weight of the group.
(h) The loading maximum in this subsection shall apply to interstate highways, and the State Transportation Department, or a local authority with respect to highways under its jurisdiction, may designate a highway, or a section of a highway, for the operation of vehicles having a gross vehicle weight of not more than 80,000 pounds which are subject to the following load maximums:
(1) 20,000 pounds on any one axle, including all enforcement tolerances.
(2) A tandem axle weight of 34,000 pounds, including all enforcement tolerances.
(3) An overall gross weight on a group of two or more consecutive axles equaling:
W = 500((LN/(N-1)) k 12N k 36)
where W = overall gross weight on a group of two or more consecutive axles to the nearest 500 pounds; L = distance in feet between the extreme of a group of two or more consecutive axles; and N = number of axles in the group under consideration; except that two consecutive sets of tandem axles may carry a gross load of 34,000 pounds each if the first and last axles of the consecutive sets of tandem axles are not less than thirty-six feet apart. The gross vehicle weight shall not exceed 80,000 pounds, including all enforcement tolerances. Except for a five-axle truck tractor or semitrailer combinations having two consecutive sets of tandem axles, vehicles having a gross weight in excess of 80,000 pounds or in excess of the vehicle gross weight determined by application of the formula in this subsection shall be subject to the maximum axle loads of subsections (a) to (c) hereof. As used in this subsection, "tandem axle weight" means the total weight transmitted to the road by two or more consecutive axles, the centers of which may be included between parallel transverse vertical planes spaced more than forty inches, but not more than ninety-six inches, apart, extending across the full width of the vehicle.
(Ord. 97-10. Passed 11-5-97.)