The pouring amount of large volume is too large, and the overall requirements are high. During the pouring, tamping and curing process, a large amount of hydration heat is generated from cement hydration. However, due to its large volume, a large amount of hydration heat cannot be distributed. The internal temperature of the concrete is higher than the temperature of the outer concrete, resulting in a large temperature difference. Due to the different volume expansion between the surface and the inside, temperature cracks will be generated, so the hydration heat is reduced, Place the concrete inside and outside