UPN: 8189    Project Number: IM 90-1(205)59    Project Name: I-90 Nemote Creek Culvert

Sprayroq image

The project is located at the crossing of Nemote Creek on Interstate 90, approximately two miles northwest of the Tarkio Loop Road interchange, and 1.3 miles southeast of the Quartz Flats westbound rest area. The eight (8) gauge steel plate pipe (SPP) culvert is 242 linear feet, with an interior radius of 12 ft.

Bulging and sagging of the steel plated panels located near the east end of the culvert were noted in 2006 and recommended for remedial action in May 2013. Maximum deflection within areas of deformation was roughly estimated to be six inches located in the upper plates of the pipe. The purpose of the rehabilitation effort is to improve the structural capacity of the pipe to reduce the chance of a culvert failure that would impact the I-90 roadway.

Due to site constraints and apparent minimal change in the areas of deformation over the past seven years, the Department proposed to use a cure-in-place-pipe (CIPP) process to provide structural enhancement and corrosion resistance.

The selected product is Sprayroq’s catalyzed, two-component coatings SprayWall. SprayWall is a procedure using self-priming, spray-applied structural polyurethane coating as the lining medium. The manufacturer states the lining allows return to active service within an hour of application. Product information including technical performance, specifications and ASTM certification can be found at: SprayWall Polyurethane Lining.

The extent of the treatment will encompass the culvert inlet to approximately 30 feet down flow into the culvert with a 360° SprayWall application. Areas of the apparent deformation will receive a thicker application of SprayWall. Standard applied thickness of the polyurethane is a range of ½"– ¾".

Work Plan
Final Report

For more information, contact MDT Research Section.