FLEXKIT – Repairing Overpasses

This past week FLEXKIT was called into service by the Nevada Department of Transportation to make repairs on the underside of the Tropicana overpass on I-15.

The underside of the overpass was damaged when a northbound truck, in the number 1 lane, struck the leading edge of the structure, removing a wedge of concrete approximately four feet long and two feet deep. A quick setting, permanent, structural repair was needed. The answer? FLEXKIT!

Once the traffic control devices were in place, NDOT crews went to work on the repair. A boom truck was positioned directly under the damaged area and an inspection took place. At the same time, crew members were mixing straight FLEXKIT (with a touch of FlexTemp to speed up the curing process) to use as a primer. The damaged area was “wetted out” to assure thorough absorption of the FLEXKIT. Once the primed area became tacky, the crew started hand packing a mixture of FLEXKIT, sand and fumed silica onto the void. The FLEXKIT mixture was placed in three-inch-thick layers to control sagging and fallout. Keep in mind that the overpass is in constant vibration caused by the continuous flow of traffic traveling over the structure. This vibration makes it difficult for conventional patch materials to adhere to the concrete while it’s curing. This is not an issue for FLEXKIT. The mixture used on this repair was 1 part FLEXKIT, 1 part sand and 2 parts fumed silica with a small amount of FlexTemp to aid in the acceleration of the setup time. Total repair time, including set-up and take-down of the traffic control devices, was 5 hours.

Fumed silica is a thickening agent made from quartz sand that is vaporized by a 3000° C flame. It is used to add volume and reduce weight. This allows the FLEXKIT to adhere to vertical or overhead surfaces without falling out due to excessive weight.

 

Remember, “Fix It with FLEXKIT and Forget About It.”