Tag Archives: concrete

Testing Bolts Epoxy Bonded into Concrete

by Brian Knight—GBI Technical Advisor

Above: The final version of the test Brian devised to determine the holding power of bolts epoxy bonded into concrete. When the load cell registered 4000 lbs, he stopped the experiment.

The email exchange with Bob Warters in the article Installing a basketball goal is typical of the process we sometimes go through to answer a technical question. Most questions do not generate laboratory testing, but, in this case, the data we had available was limited. I was able to give Bob some shear strength data on concrete block from previous tests but was unable to find specific data on fasteners bonded with epoxy into poured concrete. I suspected poured concrete would hold a bolt better, but another data point would be reassuring. Continue reading →

Repairing cracks in concrete

Repairing Cracks in Concrete

by Brian Knight—GBI Technical Advisor

Cracks in poured concrete floors and foundation walls allow water to leak into basements and cause damage. With WEST SYSTEM® epoxy, you can, in many instances, fill the cracks from the inside and stop the water penetration without digging up your yard. WEST SYSTEM epoxy’s adhesion to concrete is excellent. It is very resistant to moisture penetration, and the tensile and compressive strength of the epoxy (about 8500 psi and 10,000 psi respectively) easily exceeds that of concrete. The following process is one method of epoxy injection that effectively seals cracks without requiring excavation outside the walls. The actual filling process takes some time, so use a slow hardener if the temperature is above 60°F. Continue reading →

Patching Cracks in Concrete Blocks

by Brian Knight—GBI Technical Advisor

Someone I know patched the cracks in the concrete block walls of her house using a different technique than the one I described in Repairing Cracks in Concrete. When it rained hard, her basement took on a lot of water through cracks in the walls. The cracks ranged in size from 1/16″ wide to some so large she could see daylight through them. Since concrete blocks are hollow, injecting WEST SYSTEM® Epoxy into the cracks would be unacceptable. So she decided to fill the cracks using epoxy thickened to a mortar-like consistency. Continue reading →