A Skewed Box Culvert Solution

When selecting precast concrete manufacturers to complete a project, New York State Department of Transportation gives preference to companies with a track record of supplying high quality products. Listed on NYSDOT’s approved manufacturers list, Kistner Concrete Products Inc. of Lockport, N.Y., an NPCA Certified Plant, is a go-to precaster for state box culvert projects. The company’s latest project, in South Valley, N.Y., resolved a flooding concern.

NYSDOT and the contractor, Concrete Applied Technologies Corp., contacted Kistner Concrete Products to replace a dilapidated jack arch bridge while maintaining the precise, curved stream alignment. The surrounding area, a rural community south of Buffalo, N.Y., is a watershed that collects rainwater thanks to rolling hills and valleys. The resulting stream now passes through the culvert manufactured by Kistner Concrete Products.

Jack Michalski, project manager at CATCO, said, among other benefits, precast concrete was specified for the project since products are manufactured in a controlled environment, which requires a high degree of quality control during every aspect of the manufacturing and curing process.

“Precast units are preferred since work can progress at a faster pace than cast-in-place concrete,” he said. “Less time is spent on water diversions, pumping and the elements in general.”

Michael Kistner, owner of Kistner Concrete Products, said the company manufactured 15 box culvert segments: four left skewed, four right skewed, five standard pieces and two sloped ends. A modified pallet form was used to manufacture the skewed pieces. Each box culvert section required a 4-inch long spigot and adjoining receiving bell section joint. For the joints to align properly, tight tolerances needed to be carefully checked to maintain a 1/2-inch gap maximum, he said. Each piece is 17 feet wide, 5 feet high and weighs 28 tons. The weight is specified due to precise calculations on the high water table.

Kistner Concrete Products also supplied precast concrete headwalls and toe walls. The headwalls were attached using rebar couplers, requiring a secondary concrete pour. Kistner said all segments were delivered and installed in two days and all parties are pleased with the final product.

“Installation was delayed one-to-two days by hard rains that flooded the project site,” Kistner said. “But after the box culverts were installed in one day, rain afterward was maintained without issue by the new culverts.”