D-Cracking is the result of placing the concrete slab over a surface that has poor drainage. Poor drainage can happen because not enough gravel is used for the base of the concrete or in areas where water is trapped by other concrete such as near driveway approaches and street curbs. You also see this frequently near flower beds or plantings where water is used for the plants and it has no way to drain. The concrete slab "sits" in continuous humidity which when combined with freeze/thaw cycles break down the cell walls inside of the concrete slab from the bottom of the slab upwards.
D-Cracking is usually found near the edge of the concrete where it meets with the lawn, landscape or street curb or near open driveway control or crack joints or cracks in the slab. It shows up initially as a webbing of small cracks on the surface of the concrete. It can look like lace or spidery veins which are more obvious when humidity is present.
This webbing spreads and the cracks will start to open and separate. Eventually the concrete will crumble to gravel in the areas affected by D-Cracking. Patching the damaged areas is only a temporary solution. If the drainage is not corrected eventually the entire slab will turn into gravel.
Solution: There is no product available today that will stop the problem completely as it begins at the bottom of the concrete and works upward. Eventually the section of slab will need to be replaced. The drainage should always be corrected when this is done. However, this deterioration process has been proven to slow down when the concrete is treated with SealGreen Concrete Sealer with Salt Defense Technology. SealGreen Concrete Sealer is a siliconate-based sealer that works inside the pores of the concrete, creating a gel that permanently bonds to the concrete as it cures. This bonding action can seal hairline cracks, significantly reducing water penetration which will reduce the damage caused by the many freeze-thaw cycles of a typical winter. It helps slow down the deterioration of the concrete allowing you to get a few more years of use out of your concrete driveway, walkway, parking lot, etc.