Concrete is known for its affordability, durability, and easy maintenance. No wonder it has been the top option for homeowners and contractors used as material either for residential or commercial projects. Since it is durable, it can withstand any inclement weather and its proper installation prolongs its lifespan that can last up to 20 years or more. The poor installation method and insufficient support for concrete often lead to cracking, breaking, and splitting. To make concrete last for a long period, this is the perfect guide to do so.
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Causes of Concrete Cracks
The cracks in concrete are rooted in its installation, provided below are the usual conditions leading to concrete cracking:
Excess Water in the Mix
Concrete only requires a little amount of water, therefore, excess water in the concrete mix during the production process makes it prone to cracking. Though adding more water to the concrete mix makes it more manageable, this reduces the strength of the concrete. The excess water will evaporate from the concrete, causing it to shrink more. Shrinkage generates forces that finally pull the slab apart leading to concrete cracking.
Rapid Drying
Rapid drying of the slab increases the likelihood of cracking dramatically. Water is required for the chemical process that converts concrete from a liquid or plastic form to a solid state. This chemical reaction, known as hydration, continues for days or weeks after the concrete is poured. Since the curing process might take weeks, the concrete needs adequate water to keep the slab from drying out and splitting.
Insufficient Strength
While concrete is powerful on its own, a little steel reinforcing may make it much stronger. For patios and pathways, this may imply installing rebar in a grid pattern, or for smaller projects, the use of wire mesh during the pour may increase strength and prevent cracking.
Poor Subgrade Preparation
The natural soil beneath a concrete slab is referred to as the subgrade. Sub-grade preparation is crucial for laying a solid foundation for new concrete. The subgrade should be level, smooth and homogeneous, with good drainage, and free of any debris during installation. The concrete may sink and break if this support is not present and not observed. A smooth sub-grade will decrease any constraint when the concrete shrinks, lowering the possibility of cracking.
Lack or Improper Installation of Control Joints
To avoid splitting, plastic or hardboard joints aid in the natural movement beneath the concrete. For these joints to be effective against cracking, they must be put at the proper location and depth. In order to anticipate and direct future fractures, these intended weak points should be carved into the slab down to roughly a fifth of its depth. Any cracks are likely to occur in these weakest areas, which is why control joints are crucial.
Improper Curing
Proper concrete curing is vital for preventing cracking at an early stage. Curing is the process of preserving concrete moisture by preventing it from evaporating quickly. When the concrete loses moisture from its surface too quickly, it tends to shrink faster than the concrete beneath the surface, leading to map cracking. Though this problem is only cosmetic and has no bearing on the structural integrity of the concrete. In some circumstances, lack of curing may result in more severe cracking, which necessitates repair. Curing the concrete actively is always a recommended technique that aids in enhancing the overall integrity of the concrete and helps prevent other surface flaws such as scaling.
Types of Concrete Cracks
Some cracks can be hazardous to structural stability, while others are simple to repair. The following provide insights on cracks and what are their implication:
Shrinkage
These cracks are caused by the water drying up too rapidly during the curing process. The ambient temperature, concrete temperature, relative humidity, and wind speed can all induce evaporation and shrinkage of the slab.
Hairline
Hairline cracks can be caused by a narrow fissure in the concrete if there was hot weather while the concrete was drying. Even though it is thin, a hairline crack may run the length of the slab.
Settlement
Concrete will continue to be moved even after the installation process is complete. During this period, the concrete should be restrained by reinforcing steel or a previous concrete placement. When the surface underneath the concrete can no longer sustain its weight, the concrete will begin to shift and lose structural integrity.
Structural
Cracks in the foundation of a house or structure are mainly caused by settlement. These horizontal fractures appear a few feet from the top of the wall if there is too much pressure from water or heavy machinery surrounding the foundation wall.
Floor
Cracks at the base of a concrete slab are very frequent, but they should be repaired immediately upon noticing to avoid water and insect damage. Water pressure is usually the cause of floor cracks, in the process of fixing, the water should be redirected away from the crack.
Prevention of Concrete Cracks
Most cracks may be avoided by carefully designing and installing concrete components. In some cases, a reputable contractor may aid to avoid cracks forming in either concrete wall, patio, driveway, or deck. Here are some additional strategies to protect concrete from cracking in the future:
Cure Properly
Concrete might take over a month to completely dry and settle. Spray the concrete a few times a day for the first week to ensure there are no cracks in the surface, using significantly more water in warmer, drier weather.
Adding Control Joints
To anticipate and reroute any fractures through control joints, cut weak places into the slab. If installed properly, the fractures should appear in these weak spots rather than throughout a large portion of the slab.
Proper Amount of Water
During the building phase, check the directions on the bag or consult the manufacturer to determine the permissible water for the concrete mix. If the concrete mix is smooth, it means enough water is added. If it is somehow crumbly, gradually add additional water until all of the dry particles are incorporated. Add extra dry concrete if the mixture is too damp.
Compacting the Base
The new slab should be supported before pouring the concrete. The base beneath the concrete must be compacted or it will result in settling or creating a void.
Steel Reinforcement
Metal installed beneath the concrete helps strengthen the foundation. Prior to pouring the concrete, place the wire mesh beneath it to provide strong support for the slab.
Ways to Repair
It is recommended to provide immediate repair for the cracks in the concrete slab before it becomes a significant problem. These cracks tend to enable water to seep in and freeze, causing more damage to the concrete. In filling in these cracks, ideally, it is recommended to undercut the sidewalls and fill them with a concrete patching compound. A caulking gun can be used as well for narrow cracks that appear on concrete.
Concrete crack repair procedures may include epoxy injection, routing and sealing, grouting, stitching, drilling and plugging, and gravity filling of fractures in concrete. A suitable approach for repairing concrete cracks can be chosen based on an appraisal of the fracture in the structure for its reasons. Once the source and kind of fracture are determined, a suitable technique may be chosen.
Though cracking appears to be a natural phenomenon on concrete, it is vital to have insights about it from the installation to the maintenance stage. With careful planning and proper execution, this concrete may last a lifetime and surely will meet its return of investment. For these projects to fully maximize their potential, the aid of expertise and quality service might be a great help, this is what Tampa Concrete Solutions is known for. Check their website at (insert website) or call their hotline (insert contact number) for more details and project assistance.