486 623.13 -CURING AND PROTECTING SHOTCRETE : Unless otherwise specified, s hotcrete shall be cured as outlined in Section 601.12. Immediately after shotcreting and not to exceed 30 minutes after placement, initial curing is to commen ce. The surface of the concrete must be continually kept moist using a fogging system. Use equipment that produces a fog spray from atomizing nozzles that will uniformly cover the concrete surface. The minimum rate of fog application shall not be less 10.6 gal./h/yd2. The number and placement of nozzles shall be dependent on the discretion of the Engineer. The mist must be fine enough as to not disturb the finished surface of shotcrete. Final curing must be done through fogging, sprinkling, or a combination of burlap sacks with sprinkling or plastic -coated synthetic fabric with sprinkling. The burlap sacks and plastic -coated synthetic fabric must be kept continually saturated with water by sprinkling. Set up fogging equipment to allow complete coverage of th e area to be cured. The surface of the concrete must be continuously kept wept from the time of placement and the alternation of wetting and drying of the concrete surface will not be allowed. Perform sprinkling for final curing by using either soaker hose s or lawn sprinklers. The surface of the concrete is to not be eroded by running water. All methods of final curing must be performed for a period of 7 calendar days. If no other curing method is available due to project limitations, curing compounds can be used and must be placed in two coats of different orientations of application one vertical and the other horizontal, to ensure a complete seal. Use of curing compounds is only permitted on the final layer of shotcrete and not between layers of applicati on.
623.14 Method of Measurement :
The quantity of shotcrete to be paid for will be the number of square yards complete in place and accepted.
623.15 Basis of Pay Ment :
The quantities, determined, as provided above, will be paid for at the contract unit price, and shall constitute full compensation for furnishing and preparing of a ll materials, including reinforcing steel, all items incorporated into the shotcrete work as shown in the Plans such as anchors and bolts, placing, finishing, testing, and curing shotcrete, and all labor, equipment, tools, supplies, and incidentals necessa ry to complete the work.
623.16 Pay Items :
ITEM DESCRIPTION UNIT 623001 -* Shotcrete Square Yard * Sequence Number