On cloudy days, when the temperature is 13 degrees, the cement concrete floor should be watered and maintained. Generally, the temperature drops below 5 degrees before watering.

In the early stage of hardening, concrete will release a lot of heat when it is hydrated, but concrete is a poor conductor of heat and its heat dissipation is slow. If cooling measures are not taken, the internal temperature of concrete will rise (sometimes the temperature difference between inside and outside can reach 50℃ ~ 70℃), which will cause greater thermal expansion inside concrete, but its surface temperature will dissipate quickly and shrink due to cooling, and its internal expansion and surface contraction will produce tensile stress on the concrete surface. When the tensile stress is greater than that of concrete,

Shrinkage stress and temperature stress are the main causes of cracks in concrete structures, and maintenance is undoubtedly the most important means to eliminate the adverse effects brought by these two stresses. This is because concrete will produce hydration heat reaction and release heat during solidification, while external heat is easy to be lost, while internal heat is not easy to be lost, resulting in stress difference and cracks. The main function of maintenance work is to maintain by covering wet grass mats or storing water, so as to reduce the temperature difference inside and outside the floor structure and avoid cracks.