A structurally-deficient concrete box culvert on a major four-lane Missouri highway desperately needed repair and rehabilitation. With horizontal cracking and bowing on the exterior walls, there was concern the structure would cave in.
Initially, the Missouri Department of Transportation (MODOT) considered a project design that removed and replaced the existing twin 12-ft. by 12-ft. concrete box culverts. This would cost $379,000 and take two months to construct. It also would require use of a temporary bypass with the acquisition of land to create an adjoining ‘right-of-way’ to redirect and control traffic.
MODOT developed an alternative solution using Aluminized Steel Type 2 (ALT2) ULTRA FLO® corrugated steel pipe (CSP) from Contech to reline the existing culverts. This solution would cost $41,000 in material costs — an 89% decrease in capital costs — and only three weeks to construct. Further, since the improvements would take place inside the existing box structure, there would be no need for a temporary bypass or a ‘right-of-way’ land acquisition.
The Contech alternative was less expensive, provided the quickest construction and was most convenient for traffic flow.
MODOT District 2 provided their own labor, enabling their crew to have exposure to the new replacement methods and controlling project costs. ALT2 coated ULTRA FLO has a long history of proven durability. The first application in Missouri was in 1952 and is still in place and functioning today.
The successful Route 65 Reline project won an MODOT Practical Design Award in the Small Bridge Replacement category.