• Understanding Cracks in Concrete: Causes, Remedies, and Prevention

    May 14, 2024 | By Kenza TMT Steel Bars

    Concrete is an essential building material made of water and cement. It is seen everywhere but tends to develop cracks. The problem with these cracks is that they not only affect the aesthetics but also compromise its structural integrity. 

    Why is the Reason for  Cracks in Concrete?

    If you understand why these cracks develop in concrete, you can take up preventive measures and do proper repairs. 


    One of the main reasons that concrete develops cracks is because it does through shrinkage. When you pour concrete, it starts to dry up and lose moisture. As a result, the concrete shrinks, leading to internal stresses, and develops cracks. If you pour too much water into the concrete, it will shrink more when it dries. Mixing the concrete in proper proportions is one way you can minimize shrinkage. Uneven shrinking can happen if the temperature keeps, leading to cracks. Different types of cements also have different shrinking properties. Some shrink more than others while it cures. 

    Structural Overloading

    If you subject concrete to excessive weight or pressure, one beyond which the concrete is  designed to bear, it will crack under stress. This can include vehicles, machinery, or equipment, or inadequate reinforcement or improper structural design that does to distribute stress evenly.

    Chemical Reactions

    There are some chemical reactions that can cause your concrete to crack. For example, in alkali-aggregate reaction, the reactive metals in aggregate react with alkalis in the cement, causing expansion and cracking over some time.


    Sometimes, the soil beneath the concrete can compress or shift. It can cause the concrete above to settle unevenly, increasing its chances to crack.

    Freeze-Thaw Cycles

    Concrete in colder climates undergo a freeze-thaw cycle. When ice thaws, there is a possibility of water penetrating through the cracks. And if the water freezes after it penetrates, it will expand, exerting pressure on the concrete. If this keeps repeating, the freezing and thawing cycle can lead to cracks.

    Poor Workmanship

    Finally, like anything manual, poor handwork can give bad results. In the case of concrete, it can be improper placement, or improper finishing of concrete that can create weak spots or air pockets. 

    Remedies for Cracks in Concrete

    Let’s go through some remedies that are available so that you can diminish the effects of cracks in concrete.

    Crack Injection

    If the cracks are hairline or small fissures, a crack injection is the best method to use. During this process, we inject a specialized polymer into the crack. The polymer fills the void and prevents cracking.

    Patch Repair

    If the cracks are larger, you can use a patch repair which is commonly used in these cases. You need to first clean the crack and then fill it with a concrete patching compound and then smoothen the surface out to match the surface around it.


    If the concrete is severely damaged, you can apply an overlay. In this process, you just apply a new layer of concrete over the existing one, to cover the cracks and provide a fresh surface. 

    Epoxy Injection

    An epoxy injection is a good option for you if the crack is leaking water actively. It deals with injecting epoxy resin into the crack formed on the concrete. The epoxy resin hardens and forms a waterproof seal.

    How to Prevent Cracks in Concrete

    • Make sure your concrete mix is properly balanced, with the right amount of water, cement, aggregate, and admixtures. 
    • Keep the concrete moist and away from severe temperatures as it cures. This can help to minimize shrinkage and cracking.
    • You can add reinforcements such as steel rebars or fibers to increase the tensile strength of the concrete. 
    • If cracks are unavoidable, you can use a technique called joint placement. They are purposeful cuts that can be made into concrete to create a weak area for fractures to form. This way, the cracks form in a regulated manner, preventing random cracking.
    • You can also ensure that you use proper construction procedures. Ensure that the concrete is adequately

    To sum it up

    Using concrete is not optional. But it has its demerits- mainly cracks. But if you know the causes of cracks in concrete,  how to repair and avoid them, you can easily deal with them.


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