1. What are the methods for repairing concrete cracks?
Here's how to repair concrete cracks:
1. Filling method to treat concrete cracks: Use repair materials to directly fill concrete cracks. The construction method is simple and the cost is low.
2. Structural reinforcement method to deal with concrete cracks: mainly aimed at cracks that appear due to overloading of the building's bearing capacity, cracks caused by fire, etc.
3. Grouting method to treat concrete cracks: This method has a wide range of applications, ranging from fine cracks to large cracks, and has good results.
2. Causes of concrete cracks
1. Shrinkage of concrete
Shrinkage of concrete is an important characteristic and has a great impact on the performance of concrete. Because shrinkage causes micro-cracks, over time, the structure may crack, deform, or even be damaged.
2. Temperature stress
The reason for the cracks may be that the cement hydration heat accumulated inside is difficult to dissipate, causing the internal temperature of the concrete to be very high, the surface of the concrete to dissipate heat quickly, and the temperature difference between the inside and outside to be large. Pressure is generated inside the concrete, and tension is generated on the surface to cause cracks.
3. Insufficient reinforcement
In our actual observations, concrete structures with large reinforcement spacing and small reinforcement ratios have more cracks, and unreinforced concrete has more cracks than reinforced concrete.
4. Concrete materials and mix proportions
Cracks caused by the quality of concrete raw materials and improper mix design affect the tensile strength of concrete and cause concrete cracking.
5. Maintenance conditions
Curing is a means to harden concrete normally. The curing conditions have a great influence on the occurrence of cracks. Under standard curing conditions, concrete hardens normally and will not crack.