The Texas Department of Transportation (TXDOT) had several roadway improvement projects underway, one of which included inspecting and identifying existing culverts and small bridges in La Salle County that were in need of repair. One such culvert, located on FM 624 in Cotulla, Texas was a triple barrel reinforced concrete pipe (RCP) culvert that was severely deteriorated.
The contractor for this project, Anderson Columbia Construction, reached out to Texas Corrugators South Texas Region, a local distributor for Contech Engineered Solutions LLC. Texas Corrugators was familiar with the products manufactured by Contech and knew that there were several reline solutions available that might meet the needs of the project. After proposing multiple options that were available, TXDOT ultimately selected the use of Contech's 12 gage, polymer-coated ULTRA FLO® corrugated steel pipe (CSP) to slipline into the existing pipe. The polymer-coated ULTRA FLO would protect against abrasion and corrosion and extend the service life of the existing culvert for an additional, estimated 100+ years. Additionally, the structural design method of the ULTRA FLO liner pipe was based on carrying all live and dead loads as if it were a direct bury installation. If the existing RCP continued to break down, the new pipe would be able to bear the load fully.
The unique 3/4” x 3/4” x 7-1/2” continuous spiral rib box corrugation allowed TXDOT to maintain the necessary hydraulics within the deteriorating triple barrel RCP even though the 40-inch diameter ULTRA FLO pipe was slightly smaller than the existing pipe through which it was pushed. Although 40” is not a standard size, ULTRA FLO can be manufactured to any intermediate diameter dimension making it a highly versatile, reline pipe.
With a plant facility nearby, Contech quickly manufactured the needed liner pipe. Ultimately, there were three runs of 88 LF of ULTRA FLO that arrived to the site. Anderson Columbia Construction was able to install the ULTRA FLO pipe quickly and easily. Anderson Columbia's Project Manager, Rick Andrade, stated, "The 40” pipe we installed on FM 624 job worked beautifully, and we actually wrapped up that project yesterday (a day early)!"