The temperature regime and thermal stress state of a massive reinforced concrete slab 1.5 m high during the construction period were studied with continuous concreting to the entire height (without the device of horizontal working joints). Calculations were performed using time-dependent thermophysical and deformation characteristics of concrete, considering curing temperature via the adjusted time hypothesis – the real time was replaced by some adjusted time, which is a function of temperature. As a criterion for thermal crack resistance in this article, the deformation criterion proposed by P.I. Vasiliev was adopted: cracks are considered as absent if the elongation strain does not exceed the ultimate tensile strength of concrete. The slab was built in layers of 0.375 m with overlap intervals from 1.0 to 3.0 h. It was found that in case of consideration the layering, the thermal stress state acquires a more favorable character, from the perspective of ensuring thermal crack resistance. A decrease of dangerous tensile stresses on the slab surface to 41.7% during the period of exothermic heating of the structure was noted. The effect of reduction slightly depends on the temperature conditions of concreting, but significantly depends on the duration of the intervals of overlapping layers of concrete mixture and the rate of heat release growth. Further research in this direction can lead to optimization of measures to prevent the formation of thermal cracks during the construction period and to obtain an economic effect associated with a decrease in the cost of erecting construction projects.