(a) The contractor shall erect and maintain suitable barricades and employ watchmen, if required by the urban county engineer, to exclude traffic from the newly constructed pavement. When it is necessary to provide for traffic across the pavement, the contractor shall, at his expense, construct suitable and substantial crossings to bridge over the concrete, which will be adequate for traffic and satisfactory to the urban county engineer. Any part of the pavement damaged by traffic or other causes occurring prior to its final acceptance shall be repaired or replaced by and at the expense of the contractor, in a manner satisfactory to the urban county engineer.
(b) Curing shall continue for a period of ten (10) days; except that under extremely dry or cold weather conditions, the urban county engineer may require additional curing periods, additional covering or both.
(c) Immediately after the finishing operations have been completed and regardless of the method of final curing, the entire surface of the newly laid concrete shall be covered with wetted burlap or cotton maps laid directly upon the finished surface. The burlap or cotton mats shall be of good quality, free from dirt and other foreign matter. Burlap shall be of ten- to eighteen-ounce weight per ten (10) square feet. Cotton mats shall be composed of a single layer of mat and completely enclosed in covers of cotton cloth or burlap, securely stitched to retain its shape and effectiveness. This covering shall be kept continuously saturated until removed. It shall not be removed earlier than the morning of the day following the application.
(d) Immediately after the removal of the burlap or cotton mats, the curing shall be continued by the use of modern chemical methods approved by the urban county engineer or by the wet-earth or straw-curing method, in the following manner:
The exposed edges of the concrete shall be banked with a substantial berm of earth, and the entire surface of the paving shall be covered with earth of not less than one and one-half (1½) inches in depth or by the use of clean loose straw at the rate of three (3) pounds per square yard. In either case the entire surface and exposed edges shall be kept saturated four (4) days, dating from the removal of the burlap. If the wet earth or straw becomes disturbed or displaced, it shall be replaced immediately. The covering shall remain on the pavement until permission is given by the urban county engineer to open the pavement to traffic, at which time the covering shall be removed and the pavement cleaned and swept.
(e) Upon the approval of the urban county engineer, the contractor may substitute the ponding method of curing or he may use a modern and satisfactory sprinkling system designed for the purpose. If either of the substitute methods fail to meet the approval of the urban county engineer, they shall be discontinued and replaced by one of the above-mentioned methods.
(f) The contractor shall submit the trade name of any chemical concrete curing compound to the urban county engineer and obtain his approval before using same on any part of the work in question.