Concrete repair is a process that begins with the determination of the cause of damage, surface preparation, and decontamination, and finally execution of the repair design. The best concrete repair dallas method to use is dictated by the type and extent of damage that has occurred.it also depends on the surface location i.e. slab, indoor floor, pool deck, and driveway.
Evaluation
Damaged concrete requires evaluation to categorize the type of damage as structural or superficial. Structural repairs are required for surfaces diagonal cracks cutting across a concrete surface. Such types of repairs should be done by engineers or experienced persons. Evaluation involves documentation of any structural damages hence contracting the owner of the premises to make them aware of the situation. For concrete surfaces that are still stable and may not result in the building collapsing, the following steps can be used to evaluate the extent of damage by visual examination
- Determine whether the damage is local or widespread
- Identify if there is any corrosion of support steel
- Describe the type of surface delamination that has occurred i.e. this scaling, deeper spalling, and overlay
- Determine the type of damage as either superficial or structural
- Check to see if the cracks are still extending
There are tools used in the evaluation process to obtain more meaningful and helpful results. The use of a harmer to knock the surface will help to tell the type of delamination that has occurred in areas that have been hidden by paint. The use of tape measures may also be necessary to indicate the level of repair required. Pictures and videos can also be of help. Further examination of the concrete damages involves the use of destructive and non-destructive techniques. Samples may need to be collected for testing and analysis in the lab. Examples of non-destructive techniques are infrared thermography, impact echo, and radar. Destructive techniques may involve breaking the concrete to reveal the damages and slight drilling to obtain test samples.
Causes of Damage
One trait of concrete is that it is strong when under compression and weak under tension. The direction of the crack line is also in relation to the direction of the source of tension. Diagonal cracks can also be a result of concrete shrinking. Shrinkage can be as a result of heavy traffic in the area near the surface or due to poor compaction of the structure. The most suitable repair materials are high-quality concrete with a higher bonding strength and are long-lasting. Polymer-based materials are the best so far produced by manufacturers. There are several factors that a constructor needs to consider before settling for a particular concrete repair material.
Examples of concrete problems that require repair include
- Disintegration from freezing and thawing
Occurs due to the porous nature of concrete. When water gets trapped in concrete it freezes breaking off small flakes of the concrete surface. This mainly happens during winter and extreme cases cause scaling and total damage to concrete surfaces. This can be prevented by ensuring the proper creation of air spaces in concrete during construction.
- Corrosion of fortifying steel
Concrete has alkaline properties that aid the protection of steel used for its reinforcement from rusting. However, the presence of chlorides interferes with the passivating layer that makes concrete alkaline hence rusting is allowed. The increase in volume due to the rust and expansion of the steel creates tension causing the surface to crack.
- Drying shrinkage
Concrete is meant to have a higher moisture content compared to the amount that is used by hydration reactions. When water evaporates from the concrete surface it shrinks to a point it cracks if it did not contain enough moisture.
- Alkali aggregate reaction
This is caused by gel formation around an aggregate particle due to the presence of a reactive aggregate in the concrete surface. The formed gel on expansion destroys the concrete. This effect can be reduced using lithium products.
- Plastic shrinkage
Involves the formation of cracks on concrete as a result of the surface drying out before it is strong enough. The types of cracks formed are narrow and shallow and distort the appearance of the concrete surface. Such issues can be solved by ensuring the curing process is done effectively or by the use of synthetic fibre reinforcement.
- Delamination
This is caused by premature finishes and forced sealing of concrete. This is because air and bleed water end up being sealed within, hence creating bubbles.
- Cracks due to structural loads
These are damages that result from a lack of strong reinforcement by steel. In case of heavy loads, the surface begins to form cracks which widen with time.
Conclusion
Most concrete repairs are not durable and fail in less than 2 years’ time. This is because most repairs are not done in the right way using the right materials. Concrete repairs require high-quality material and expertise, especially when dealing with structural damages. Some concrete issues require immediate attention since they can cause vital accidents when not taken care of and reinforced immediately. It is therefore important to understand the cause and extent of damage and the right procedure for repair services.
