Concrete Repair
Poorly compacted soil, erosion and ground settling can create a void under existing concrete, causing cracks and unlevel concrete and should be repaired. Professionally repaired concrete can have a life expectancy of approximately 20-30 years. In order to ensure the integrity of the repair, the proper measures must be made to create a strong bond between the new material and the old material.
The concrete used in your steps, driveway, sidewalk, etc. consists of four basic elements: water, sand, gravel, and cement. These elements are held together by the cement acting as a "gluing" agent. As soon as water is added to a cement mixture, a reaction occurs resulting in the formulation of tiny crystals. The more crystals that form, the stronger the bond will be.
Creating a uniform application of a strong bonding concrete mixture to an existing concrete surface or structure is key for a reliable concrete repair job. Typically, specially formulated gluing compounds are used to assist with the creation of this uniform application. Simply applying a new concrete mixture to old or existing concrete is not conducive to a "permanent" repair.
For larger concrete repairs, insertion of proper pinning may be necessary before the repair or patch is applied to increase the longevity and stability of the repair.
Remember, an ounce of prevention is worth a pound of cure. If your concrete surfaces or structures are in need of repair, the sooner the better. Left unattended, smaller repair jobs could develop into larger ones.