When a concrete bridge deck began cracking almost immediately after placement in July 2015, the Texas DOT decided to test the two-step Deck-Sil repair-and-waterproofing system patented by Advanced Chemical Technologies Inc. of Oklahoma City. Bridge engineers wanted to compare the method’s performance to an overlay.
Using a spray bar powered by an air-operated diaphragm pump, DOT crews applied PS-1700 silane-based penetrating sealer to the pavement. The solution soaks into the top ¼ inch, including cracks, to keep water — concrete’s No. 1 enemy — from infiltrating the pores.
In the hour it took the sealant to dry, crews mixed up EP-1700 epoxy. Formulated to work with PS-1700, the extremely low-viscosity epoxy forces the penetrating sealer even deeper into the concrete, “healing” cracks and providing a water-repellent layer at least ½ inch thick. Crews poured the solution into the largest cracks and evenly spread the rest over the bridge deck with industrial push brooms.
To provide skid resistance, they used a sandblasting pot to evenly distribute sand over the pavement to point of refusal. The four-lane bridge was open to traffic six hours later.
The project cost $20,000 and took about two days.
This was an unusual situation, hopefully one that road agencies don’t often encounter, that required a unique repair method. But the product upon which the solution is based is well known.
Since their introduction to the U.S. in 1976, more than 30 state DOTs have approved silane penetrating sealers for bridges to retard corrosion of steel rebar. But for the most part, they haven’t applied the same logic to concrete roads. Similarly, many municipalities aren’t deploying a simple preventive measure that extends the service life of concrete parking decks, driveways, and sidewalks for pennies on the dollar.
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