The Provencher Bridge, completed in 2003 in Winnepeg, Manitoba, Canada, was experiencing excessive cracking in its concrete deck. The surface of the 250 meter-long five span, precast, post-tensioned bridge had a number of small cracks in addition to about 1600 linear feet of larger width cracks. Consultants Wardrop Engineering and the city maintenance engineer contacted Concrete Restoration Services Inc., Winnipeg, Manitoba, Canada, to inspect the structure and make a recommendation for a repair procedure and material. Joe Solomon, chairman of Concrete Restoration Services recommended the application of Sealate T-70 MX-30 manufactured by Transpo Industries Inc., New Rochelle, N.Y. Though Sealate T-70 MX-30 has the same bond strength as Sealate T-70, with the MX-30, the sealer will stretch to accommodate normal movement within the structure.
The crew treated the larger cracks individually to make sure they were filled with the sealer. Once the material cured, the entire surface of the bridge was treated with a flood-coat. This not only filled the smaller cracks that were too extensive to seal individually, but it also allowed the resin to penetrate into any open pores in the concrete. The process increased the concrete surface strength and reduced the permeability of the deck. A light broadcast of coarse sand applied before the flood-coat increased the skid-resistance until the excess sealer wore off the surface. The process took about two weeks to complete. Solomon says the sealing will improve the serviceability of the concrete.
For more information on this product, contact Transpo Industries Inc. at 800-321-7870, www.transpo.com.