Miscellaneous RamblingsVoids under concrete? SlabJack Geotechnical can help.

February 10, 2018by Jerald Sargent0

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One of the most common problems customers tell us about are voids or hollows underneath their concrete. In many cases it leads to settling and worse, cracking, particularly on driveways and garages.

By filling these voids with high density polyurethane foam, settling is reduced, slab fractures are eliminated and years are added to the life of your concrete.

Why do voids develop under concrete?

First let’s talk about what a given cubic foot of soil looks like. You might be surprised to know that roughly 20% of a given amount of soil is simply empty space. The larger the material in the soil (rocks, gravel sand) the larger the amount of void space. This comes into play when water is added to the soil. Whether this comes from seasonal run off, high water tables or simply rain, when soil is saturated and then drains it carries away fine particles. This can further consolidate soil and hence, settling. Additionally, the freeze and thaw cycle also can create voids, this is how most potholes develop on our roadways.

Symptoms of voids –

Hollow sounding as cars, skate boards, balls bouncing etc. are driven, ridden or bounced on it. Water draining through control joints and/or cracks is indicative of developing voids. Deterioration of control joints and cracks because as slabs move against each other small pieces chip off. Cracks.

Acting sooner rather than later saves money and preserves your concrete. It will not be less costly to fix it later.

If you have the telltale signs of voids under your concrete call the concrete raising and leveling professionals today,



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