61-8-313. Special speed limitations. (1) A person may not drive a vehicle equipped with solid rubber or cushion tires at a speed greater than 10 miles per hour.

(2) A person may not drive a vehicle over a bridge or other elevated structure constituting a part of a highway at a speed which is greater than the maximum speed which can be maintained with safety to the bridge or structure when the structure is signposted as provided in this section.

(3) The department of transportation upon request from a local authority may, or upon its own initiative shall, conduct an investigation of a bridge or other elevated structure constituting a part of a highway, and if it finds on investigation that the structure cannot safely withstand vehicles traveling at the speed otherwise permissible under this chapter, the commission shall set the maximum speed of vehicles which the structure can withstand, and the department shall erect and maintain suitable signs stating the maximum speed at a distance of not less than 100 feet before each end of the structure.

(4) Upon the trial of a person charged with a violation of this section, proof of the setting of the maximum speed by the commission and the existence of the signs is conclusive evidence of the maximum speed which can be maintained with safety to the bridge or structure.