Crack resistance is the ability of a material to resist various mechanical influences (internal and external), which leads to the development of cracks.
The indicator is characterized by the time before cracks appear under the influence of temperatures, bending forces, compression, tension, and chemical processes. Accordingly, the longer a reinforced concrete structure does not lose its integral structure during operation, the higher the crack resistance of the material. Crack growth is observed if the intensity coefficient and stress growth exceed the available limit values of the material.
A correct assessment of crack resistance can only be given by studying concrete samples. The study is an effective method of predicting the stability of the structure in the long term.
WHAT AFFECTS THE CRACK RESISTANCE OF CONCRETE?
The rate of crack formation in a reinforced concrete structure can be influenced by both external factors, such as humidity or temperature, and the quality of the material itself. To determine the value of crack resistance, the indicators of material strength, elasticity, shrinkage, creep, etc. are taken into account. The effect of negative factors can be enhanced by the characteristics of the structure itself, its shape, and dimensions.
Studies show that the quality of cement can also significantly affect the rate of crack formation. For example, cement with a low hardening rate is in most cases less prone to cracking. Therefore, it is possible to objectively judge the crack resistance of reinforced concrete structures only in a complex.
HOW TO INCREASE THE CRACK RESISTANCE OF CONCRETE?
Even minimal cracks can provoke the destruction of the structure in the future. In the crack zone, the reinforcement is exposed, as a result, corrosion appears, which leads to even greater crack expansion. Increase the crack resistance of concrete by using the following actions:
- adding special reinforcing additives to the concrete mixture;
- magnetizing water;
- reducing the composition of undesirable components;
- creating an additional surface layer, the composition of which will prevent the appearance of microcracks;
- formation of optimal microstructure of concrete.
The main task when choosing the optimal composition of the concrete mix is to find such a ratio at which it will be possible to achieve maximum strength of the material with minimal negative qualities.
HAS A CRACK APPEARED? A QUALITY SOLUTION TO THE ISSUE
To properly repair cracks in reinforced concrete structures, the cause is first identified. Work on eliminating cracks in reinforced concrete structures can be conditionally divided into 2 areas:
- Repair and restoration of the bearing capacity of reinforced concrete structures.
- Construction of new substitutes or unloading of structures.
To eliminate cracks in reinforced concrete structures, the injection method is most often used. A special strengthening solution is pumped into the problem area under pressure. To restore the protective layer, the shotcrete method is used: a repair mixture is applied under pressure to the repaired and cleaned surface.
If defects in concrete have appeared as a result of soil shrinkage, leaching or loosening, this problem must be eliminated immediately.
When contacting Premium Technologies specialists, you will be offered the most modern and effective methods of strengthening the base of reinforced concrete structures to maintain their durability, strength and reliability.