In case you missed Part 1 of this blog series, we took a comparative look at a common question in our field which is the difference in lifting with structural polyurethane resin versus mudjacking. This blog will look at the second most common question we hear, “How strong is this foam?”
When you hear the word “foam” you may think of a couch cushion, memory mattress, or even soft packing material. Your second thought would be, “There is no way this stuff will lift a structure.” You would be right and we would agree. Soft packing material cannot lift a building. But do you know what can lift a building? High density, structural polyurethane resins. Much stronger presence than the word “foam”, wouldn’t you agree? Let’s dig into some of the facts and uses.
To give some perspective, let’s look at the properties of stiff clay and crystalline bedrock.
These materials have a load bearing capacity of 4,000 psf and 12,000 psf respectively (National Homebuilders Association). Our lifting foams yield a compressive strength of up to 100 psi in a free rise state or put another way, 14,000 psf. This makes our resins stronger than bedrock just in a free rise state and much less stressful on the soil.
Let’s not miss the comment above, free rise state. This refers to parts A and B of our resin mixing together, and being allowed to expand freely. In most every scenario, our lifting foams will be confined when in use for repairs, either under a concrete structure, under the soil, or both. Depending on the confinement rate, the psi strength of the polyurethane resins we use can increase between 39% and 79%. Do the math on that!
To date, our structural polyurethane resins have been used to lift and stabilize the following:
• Heavy equipment slabs
• Commercial structures
• Airport runways supporting jumbo jets
• Railway beds supporting freight trains
Needless to say, this isn’t your average “foam”. When used in the right application, the facts and uses above more than justify this high density, structural, polyurethane resin for your lifting, leveling, and stabilization needs. For more information, call 601-966-7821 or visit our website www.helmspolyfoam.com.
Be on the lookout for Part 3 of this series where we compare lifting existing concrete to the tear out and replace method.