1-30-97

CELLULAR GROUT 

216-M-047

The Standard Specifications are revised as follows:

 

SECTION 216, LINE 1, INSERT AS FOLLOWS:

 SECTION 216 C CELLULAR GROUT

 

 

216.01 Description. This work shall consist of mixing and placing controlled low density cellular grout, CLDCG, to fill the voids between an existing culvert pipe and a polyethylene culvert pipe liner and at other locations as shown on the plans or as directed.

 

 216.02 Materials.

 

Fine Aggregate. . . . . . . . . . . . . . . . . . . . . . . . . . . . .904.01

Fly Ash . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .901.02

Foam Concentrate. . . . . . . . . . . . . . . . . . . . . . . . . . ASTM C 796

Water . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .913.01

 

Admixtures, retarders, and plasticizers used shall be in accordance with the foam concentrate supplier's specifications. Portland Cement shall be in accordance with 901.01(b) except type II cement shall not be used.

 216.03 General. CLDCG shall be made using the preformed foam process using foam generating equipment calibrated by the foam manufacturer to produce a precise and predictable volume of foam. The foam concentrate shall be certified by the manufacturer to have specific liquid/foam expansion ratio at a constant dilution ratio with water.

The equipment used to produce the preformed foam, and all equipment used in the mixing, pumping, and placing shall be certified as to its suitability by the supplier of the foam concentrate.

The Contractor supplying and placing the CLDCG shall be certified by the foam concentrate supplier and shall be capable of developing a mix design, batching, handling, pumping and placing CLDCG under the project conditions.

 216.04 Mix Design. The specific job mix shall be submitted by the foam concentrate supplier certified CLDCG contractor to the Engineer for approval prior to use on the project. The mix shall have a minimum 28 day compressive strength of 1040 kPa (150 psi). The mix shall be tested and verified in accordance with 216.05 or shall be approved based on prior acceptance and suitable performance on Department projects.

 (a) Mix for Gravity Flow or Low Pressure Pumping Placement. A mix shall be delivered to the job site in a truck mixer in accordance with 702.09 filled to half its capacity. The foam concentrate shall be added to the cement mix in the truck and mixed to a uniform consistency.

 (b) Mix for Low Pressure Pumping Placement. A mix shall be batched on site in a deck mate or a similar device. Small batches of approximately 1 cubic meter (1 cubic yard) shall be mixed and pumped in a continuous operation.

 216.05 Testing. For each day worked or for each 100 cubic meters (100 cubic yards) placed, four test cylinders measuring 75 mm by 150 mm (3 in. by 6 in.) shall be cast. The cylinders shall be prepared, hauled and tested for compressive strength in accordance with ASTM C 39, except that curing shall be in accordance with ASTM C 192. The cylinders shall be obtained from the point of placement.

 216.06 Placement. Block and mortar bulkheads shall be placed at both ends of the culvert. A 50 mm (2 in.) vent hole at the crown and a 25 mm (1 in.) hole at the invert shall be placed in the downstream bulkhead. An access hole sized to facilitate the method of grout input and a 50 mm (2 in.) air vent shall be placed at the crown in the upstream bulkhead.

The CLDCG shall be placed from the upstream end of the culvert where practical. The vent holes in the downstream bulkhead shall be plugged as soon as grout begins to flow out each hole. The 50 mm (2 in.) air vent in the upstream bulkhead shall be kept clear until grout begins to flow out of it. It shall then be plugged.

The CLDCG shall be placed by one of the following methods to completely fill all voids within the annular space.

 (a) Gravity Flow. CLDCG placed by this method shall be limited to a maximum length of flow of ten feet for each foot of available head per access hole. Additional access holes, where required, shall be drilled from the top and sleeved with 150 mm (6 in.) pvc piping.

 (b) Low Pressure Pumping. CLDCG placed by this method shall have a maximum length of flow limited only by the safe allowable load that can be applied to the external wall of the liner. Additional access holes, where required, shall have a minimum diameter of 100 mm (4 in.) and shall be drilled from the top and sleeved with pvc piping.

 216.07 Method of Measurement. CLDCG will not be measured for payment.

 216.08 Basis of Payment. The cost of CLDCG shall be included in the cost of the polyethylene culvert pipe liner.