Concrete is a material widely used in construction. It isn't surprising that many are familiar with the peculiarities of working with it. But sometimes, it happens that even experienced contractors make many mistakes while working with a concrete overlay. Often, after pouring a concrete screed, it'll suddenly crack. In this case, the performance characteristics of the material deteriorate significantly.
The presence of cracks in the concrete indicates problems in the pouring. Cracks in concrete always appear, even in new structures. Splitting of concrete occurs due to a violation of technology or proportions of materials. The formation of cracks negatively affects the bearing capacity of the walls, but the problem can't be completely avoided. It's necessary to monitor the width of the formed cracks and eliminate them in time.
So, how to avoid cracking, what reasons can be hidden behind such a phenomenon and why does concrete crack at all?
Let's discover!
How Cracks Affect?
The appearance of cracks affects the further construction object:
It affects the ability of the structure to perceive acting loads.
It significantly impairs appearance.
It reduces the service life of the structure.
It reduces strength characteristics.
Reasons for Cracks in Polished Concrete Floors
External Factors
Deformations are the main reason for the formation of cracks and defects on the surface under the influence of external forces. Here are the following reasons:
Bendings are formed perpendicular to the steel reinforcement bars, which stretch under the influence of bending loads. Deformation traces originate in the middle of the maximally deformed section and stop where there is no influence of bending processes.
A shear that acts diagonally with respect to the longitudinal axis of the bar. Outwardly, such defects coincide in direction with the transversely applied force and originate from traces of bending deformations.
Structural tensile stresses that can be aligned with or parallel to the axis of the reinforcing bars. Traces of central tension are transverse and are located perpendicular to the longitudinal axis of the structure.
Violation of the requirements for the correct installation of reinforcing bars located at the corners of the strip base. Installation of anchors, performed with deviations, leads to delamination of the protective layer that protects the reinforcement, manifested itself in the form of cracks located parallel to the embedded reinforcement elements.
Internal Factors
The result of internal deformation of the concrete mass is stress associated with the following points:
A sharp temperature drops in-depth and on the surface can crack the floor. Such defects arise when the mixture is quickly cooled with water, air and when the cement ripens, a significant heat release occurs. If the value of internal stresses is greater than the strength characteristics of the concrete mass, surface cracks appear. When the temperature changes, cracks start appearing.
An accelerated drying under the influence of direct sunlight, high ambient temperature, and wind.
Other Reasons for Cracking
The other main reasons for the cracking are:
Excessive concentration of moisture in the soil, causing it to rise.
Compression of the soil associated with the operation of the drainage system.
Avoiding the rules for installation of concrete or errors in its material calculation.
Premature application of forces to a concrete mass that has not reached its operational strength.
Inaccurate selection in the optimal cross-section of steel reinforcement.
Violation of the placement points of the steel bars.
Air pockets associated with poor sealing.
Failure to comply with the holding time of the solution.
Deep corrosion of the reinforcement inside the monolith.
Shrinkage and temperature processes occurring in the initial and final stages of solution hardening.
Seismic or technogenic reasons.
In most cases, there is a combination of a group of factors that contribute to the violation of the integrity of the array.
Rules to Follow For Taking Care of Concrete Floors
In order not to crack the concrete after pouring, it's necessary to provide it with appropriate care, which is a set of measures that contribute to a favourable regime of holding the composition until it reaches its operational strength. Neglect of these measures can cause deformation of the massif, reduce the rate of strength gain, and cause disruption of integrity.
The set of measures aimed at achieving the brand strength of concrete, ensuring integrity, consists in performing the following tasks:
Ensuring the minimum shrinkage of the poured composition;
Prevention of accelerated drying of the mixture;
Neutralization of temperature differences;
Prevention of mechanical effects and the influence of chemical reagents.
Conclusion!
Now, you know why concrete cracks. By observing the recommendations given, you need to carefully care for the concrete surface because cracking can be prevented. The professionals of polished concrete floors in Melbourne can perfectly handle the cracks. Hence, taking into consideration every point will help in determining the operational strength of concrete floors.
