From heat and moisture to the weight of heavy loads, several possible causes can contribute to concrete cracking. Although some cracks are common, others should be cause for concern. Knowing how to identify different breaks, as outlined here, will make it easier to determine which concrete repairs are needed to restore your investment.

A Guide to Concrete Cracks

1. Crazing Cracks

The hairline fissures that stretch out in different directions like veins are called crazing cracks. These fine breaks are confined to the top slab and won’t compromise the structural integrity of the installation. The lines appear when the surface dries out and shrinks. Contractors minimize this by keeping the material wet during installation and moist with damp burlap cloths for three days afterward. Applying a thin overlay will repair the cracks.

2. Expansion Cracks

A large break in a concrete slab could be an expansion crack. These fractures develop when the material is exposed to heat. High temperatures cause concrete to swell, placing pressure on surrounding slabs, brick foundations, and anything else it abuts. If the neighboring material doesn’t give, the stress will cause the concrete to crack.

Concrete contractors should install expansion joints between the slabs. Made of rubber or another flexible material, the joints shift to accommodate the expansion. If you already have wide cracks, a concrete repair technician can dislodge and remove the damaged area, clean out the hole, pour new fill, and seal the surface.

3. Settlement Cracks

Before installation, contractors grade the ground to make sure it is level before the concrete is poured. If the subsurface isn’t level or the soil can’t accommodate the weight, concrete will settle unevenly, causing settlement cracks to form. To fix the wide gap left in a slab, concrete repair technicians will excavate the area and apply a layer of sand to compact the soil and level the subsurface before pouring new concrete.  

If you notice any cracks in your concrete, contact the technicians at Kingdom Concrete in Charlotte, NC, to restore the safety and functionality of your driveway, sidewalk, or patio. These construction experts see their projects through from start to finish, and provide top-notch excavating and grading to prepare the worksite and ensure your concrete is mixed and poured correctly. For concrete repairs in the Mecklenburg County area, call 704) 747-4133. See photos of the team’s work online.