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Why Do You Have Concrete Sidewalk Cracks?

Have you ever wondered why you have cracks in your concrete sidewalk? This article explains the causes of cracks in concrete sidewalk slabs.

When you own property, it’s a good idea to get wise about concrete cracks. Here we explore the difference between intentional and unintentional cracks in concrete sidewalks and what you can do to take care of your concrete sidewalk slabs.

Good Cracks

Most sidewalks feature intentional cracks to allow concrete slabs room to expand and contract due to weather. If sidewalks are poured as a single continuous slab, they are practically guaranteed to develop problems such as cracks, buckling, and breakage. These problems are, of course, undesirable and can pose a serious safety risk. To avoid these problems, a contractor pours a sidewalk as multiple individual slabs with pre-planned cracks. These cracks are carefully and evenly spaced before the first drop of wet concrete is poured and will help ensure the sidewalk is resistance to weather-related expansion or contraction.

While these intentional cracks ensure a resistance to weather-related stress and potential damage, concrete slabs will eventually develop cracks or other damage over time.

Bad Cracks

Weather tends to be responsible for most issues regarding construction, especially when it comes to concrete. Climates that typically experience high levels of moisture due to rain, humidity, or frequent freeze/thaw cycles are even more susceptible to concrete cracks. Long term exposure to just about any kind of weather will eventually cause materials to break down. In the case of concrete sidewalk slabs, this means cracks, sinking, and breakage.

These issues can also be the result of poor construction practices. For example, if the contractor did not properly prepare the soils that lie beneath the slab, voids in the soil may develop quicker and result in a cracked or sinking slab. Incorrectly blending the concrete mix and an improperly cured slab can cause a faster breakdown of the concrete, again resulting in cracks, breakage, or sunken slabs.

Repairing Cracked or Damaged Concrete Sidewalks

Thankfully, as much as we can rely on concrete sidewalks eventually cracking, we can also rely on solutions. There are a few options available for concrete sidewalk repair. The option that comes to mind first for many people is simply replacing the cracked slab. However, this option can be costly in both time and money, as the old slab must be removed and hauled away before a new slab can be prepped for and poured.

A more cost-effective option is simply having the cracked concrete slab repaired via slab jacking. There are two main options for slab jacking repairs:

  • Mud Jacking: Mud Jacking involves injecting a mixture of mixture of water, soil, sand, and cement beneath the concrete slab. The mixture fills voids in the soil beneath the slab and hardens to create stability. This process can lift a sunken concrete slab back to its original position.
  • Foam Jacking: Foam Jacking is very similar to Mud Jacking, except instead of a mixture of water, soil, sand, and cement, a special polyurethane foam is used. The polyurethane can typically travel farther and expand much more to fill voids. It also integrates with the loose soils beneath the slab, creating a very strong material and bond. As the polyurethane expands, it lifts the sunken slab back to its original level.
If you’ve found yourself in need of concrete sidewalk crack repair, contact us today to locate a reliable contractor in your area.

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