The spacing, location and pre-molded fiber shall be the same for expansion joints for curb and gutter as that specified for expansion joints for portland cement concrete pavement. Two dowel bars shall be used to fasten abutting sections of concrete curb and gutter. These dowels shall be of the same material, size, covering and the like as provided in § 5.25 of this chapter except that they shall be placed on centers of not less than 12 inches and not more than 18 inches.