Concrete Sidewalk Crack Repair

Sidewalks crack. It can't be prevented, but it can be repaired.

Sidewalks are virtually impossible to construct so that they do not crack. A variety of factors can cause cracking. The method you choose for repairing the damage depends on the type of damage, the cause and whether you can correct the cause. Keeping sidewalks repaired improves safety and helps make them look better.

Slab-jacking

To repair a slab that has cracked and been pushed up or dropped, the broken ends will need to be raised or lowered so they meet again. Dig underneath the ends at the break and put hydraulic jacks underneath. Raise both ends until they don't touch; then lower them until they come together. When the ends are level, prop them up with a block or brick. Then pour wet concrete into the cavity underneath. Once the concrete sets, shovel the dirt back in to place and repair the cracks.

Concrete Grinding

To repair a slab that is bucked up on one side or the other, you can grind down the high side with a heavy concrete grinder until the two ends are even. This doesn't repair the underlying problem, but it can offer a quick fix if you are limited by time or budget. Once the ends are level, repair the crack where the sidewalks come together using one of the crack repair methods.

Crack Repair

To repair a crack or pit, use a grinder to cut along the edges of the crack or pit so that the edges are closer together at the top and wider at the the bottom, like an upside down "V." Once you've prepared the area and cleaned it out, you can use a variety of commercial adhesives with concrete crack repair compounds to fill the gap. Finish it the same way you'd finish the original sidewalk. Once the repair compound begins to set, resurface the patch with a trowel and broom to blend with the original sidewalk.

Replacement

If the cause of the sidewalk damage is not removable or repairable, the sidewalk may need to be moved. You'll need a jackhammer to break up the old damaged section and a concrete saw to cut the ends straight. A new section will have to be laid out, reinforcement wire laid and concrete poured in the new position.

References

• Concrete Network: Fix and Color Your Concrete Walkways and Sidewalks
• Oregon on the Bay: How to Repair Sidewalks
• Radon Seal: Concrete Crack Repair Methods
• Abuchon Hardware: How to Repair Concrete
• Ask the Builder: Concrete Cracks