For the purpose of paying the cost of grading, paving, repaving, graveling, regraveling, macadamizing, remacadamizing, or improving the road or roads in any road improvement districts, the board of trustees shall have the power and may, by resolution, cause to be issued bonds of the road improvement district to be called Assessment Paving Bond of Road Improvement District No. ... of ........ County or ........ Counties, as the case may be. Such paving bonds shall be payable within the time provided by section 39-1627. They shall bear interest payable annually or semiannually, with interest coupons attached, payable serially, to be issued in such denominations as may be deemed advisable.