Massive Spincast Culvert Rehab For INDOT

By Jeff Griffin, Senior Editor | September 2012, Vol. 67 No. 9

Centri-Pipe’s manufacturer says the product and process are designed to provide waterproofing, sealing, structural reinforcement and corrosion protection for sanitary and storm culverts without trenching and at a significant savings in costs. It can be used in pipes of diameters from 30 to 120 inches.

CCCP was specified on selected culverts because pre-qualified CIPP contractors were not capable of installing liners in these sizes, said Bates. The INDOT pipe committee already had researched CCCP and was interested in utilizing it on a project, he added.

Process
Bates describes the CCCP process.

“The first step,” he said, “is determining the condition of the host pipe and taking accurate measurements of its dimensions and depth of cover. Because no water can pass through the culvert during CCCP installation, a bypass pumping system must be set up.”

Next is a thorough cleaning of the host pipe invert and removal of all debris in pipe configurations. The entire inside surface then is pressure washed to remove loose material.

For inverts missing portions or deteriorated to the stage where structural integrity is lost, crews pump in self-consolidating mortar to fill damaged inverts and permanently seal the bottom of the pipe making a new, watertight base and providing a new floor that can be flat or contoured to the pipe’s shape. For the I-74 projects, AP/M PL-12,000 is being used. A day’s curing is necessary before proceeding to the spincasting application.

“The equipment,” explained Bates, “includes the spincaster machine itself, mortar mixer and pump, a computerized winch, an air compressor, various hoses, centralizers, and the equipment to unload pallets of Centri-Pipe’s PL-8,000 material to be applied by the spincaster.”

Usually the high-speed spincaster is placed in the center of the pipe at its downstream end.

“The material is applied via the equipment in varying lifts of 1/4 to 3/4 inch,” said Bates. “Generally one application is made per day. Upon completion of the final lift, a curing compound is applied to the entire surface of the rehabilitated structure.”

PL-8,000 is a high-strength, abrasion- and corrosion-resistant fiber-reinforced mortar based on advanced cements and additives plus mineral, nano and polypropylene fibers. PL-8000 can be applied to concrete, clay, metal and brick culverts,