Most concrete areas are designed for foot traffic. This leads to a huge liability issue when the surfaces become cracked and uneven.
For properties over 30 years old, the concrete starts to wear out and the surface can spall away creating problem footing. Concrete provides excellent performance throughout the service life of the structure when it is mixed properly and caution is taken during the curing process.
However, once the mix has been laid and dries, the aging process begins. Without ongoing maintenance, water may enter through cracks and holes may form, undermining the substrate. In this case, the most effective form of concrete repair is to remove and replace the deteriorated area.
REPAIRS, REMOVAL & REPLACEMENTS
Cracked concrete sidewalks and curbs are trip hazards and can be a major liability. Our highly trained crews can quickly remove your deteriorated concrete and replace it with new concrete that meets the surrounding grade evenly and looks great. We have the equipment and manpower to get the job done quickly, safely and with precision.
Concrete repair problems are as varied as their solutions. Each condition requires a clear understanding of what is expected of the repair including protection needs, appearance and load carrying requirements. From residential homes to high rise commercial properties, the threat posed by deteriorating concrete is a major one. As specialists in concrete repair, we can develop cost-effective solutions for your specific project.
Concrete repair contracting has always been a core activity of our business. Our solutions don’t address a quick-fix approach, but rather ensure the guaranteed long term performance of every repair.
Our concrete repair service includes but is not limited to the removal of old and weak concrete and the cleaning and patching of cracks, holes and spalls. Low and exposed aggregate areas can be totally resurfaced, avoiding the expense and inconvenience of demolition.
Our commitment to continual improvement and development enables us to offer effective and economical concrete repair solutions to a wide range of structural problems affecting properties from residential homes to commercial buildings, historical monuments and public sector structures.
We are continually upgrading equipment and improving methods and techniques of concrete repair and construction and we maintain the highest possible standards of workmanship.
Our qualified Engineers are on hand to offer expert technical assistance and advice, and we welcome the opportunity to carry out site inspections and provide estimates.
What Causes Concrete Damage?
Reinforced concrete is a very durable construction material but it needs to be maintained like most other products if it is to achieve its design life.
Corrosion
Apart from physical damage to the concrete, the main reason for deterioration is corrosion of the reinforcement. One mechanism by which the passive surface conditions of reinforcing steel can be disrupted, and serious corrosion damage can set in, is known as carbonation. Through the ingress of carbon dioxide from the external atmosphere and its reaction with the pore solution, the pH of the pore solution tends to decrease (become more acidic).
A decrease in internal pH levels to around 8 has been reported. The carbonation “front” gradually penetrating into concrete can be revealed on cross sections treated with an indicator solution. When this “front” reaches the embedded reinforcing steel, it is clearly more vulnerable to corrosion damage. Relatively porous concrete, wet/dry exposure cycles, low concrete cover and relatively high levels of carbon dioxide have been associated with an increased corrosion risk.
Chloride-induced attack
A more complex reinforcing steel corrosion mechanism is chloride-induced attack. Harmful chloride species can originate from the original mix ingredients or from the external environment, notable deicing salts applied in cold climates and marine exposures. Once conditions conducive to corrosion damage on the reinforcing steel surface have been established, the formation of voluminous corrosion products will generate tensile stresses in the concrete and subsequent spalling on the concrete cover.
Extensive cracking in, and loss of, the protective cover obviously leave the reinforcing steel particularly vulnerable to further corrosion damage from the external environment.
Settling
Settling of poorly compacted fill and/or freezing and thawing of the sub-grade are common causes for concrete slab instability. To repair this defect, wire mesh reinforcements are used to increase tensile strength (resistance to forces that bend and pull a material). The wire mesh stabilizes concrete by preventing cracks or joints from opening up or shifting vertically. Water loss and shrinkage can also cause cracking in concrete. To remedy this, polypropylene fibers are added to the concrete mix. These fibers effectively block cracks.