Cause analysis: There are three main reasons for this kind of problem as common concrete. Concrete strength did not meet the design requirements. The construction quality of base course is thin or sinks to form broken board. Insufficient maintenance or not cutting expansion joints in time.
Preventive measures: Strictly control the quality of concrete and construction technology to ensure strength. The construction of concrete should be checked and accepted at the base level. If it is not qualified, the construction of coloured concrete can not be stopped. Strictly cut expansion joints according to relevant technical requirements, when the compressive strength of cement concrete reaches about 30% of the design strength, it should stop the joint cutting operation. It can also confirm the appropriate time of joint cutting by trial cutting method at the construction site. If the weather is hot or the temperature difference is large, skip cutting can be stopped in the middle first, and then repair cutting in order to prevent the concrete slab from cracking before cutting.
For the color concrete pavement demoulding powder can stop the maintenance within 24-36 hours before water curing. After removing the demoulding powder, it can be maintained with water, film or curing agent, but it can not stop the water conservation with straw bags and other appliances. Colored concrete is determined by its technological characteristics, and its quality is one-time survival through manual operation of workers. Therefore, only after long-term training and engineering theory can the construction team truly achieve the chaotic connection of working procedures, complete every detail within the limited time of concrete gradual hardening, and ensure the construction quality. In addition to the key technologies mentioned above, in the construction of ordinary concrete, please. The technical links such as vibration, finishing, expansion joint and maintenance are indispensable. Therefore, the operation should be more standard and abundant so as to achieve the desired effect and prevent common quality problems.