Thermal Stressed State in Massive Concrete Structures in the Winter Building Period

The article deals with issues of the thermal cracking resistance in massive concrete and reinforced concrete structures during the building period. The paper gives the calculation results of thermal stressed state in massive foundation slabs with different time organization of the thermal protection. It was found that the thermal crack resistance is fully guaranteed when the insulation is installed immediately after concrete has been placed or it has been placed with short delay. The delay can be allowed if the relative tensile strain of the concrete does not exceed the tensility limit. The acceptable delay ranges from 8 to 30% of time it takes to reach the maximum temperature in the concrete block. The surface insulation installation at the time of the temperature peak inevitably leads to the formation and development of cracks