Eight-shaped crack

For mass concrete, the hydration heat release of cement is relatively concentrated, and the internal temperature rise is faster. When the heat dissipation conditions inside and on the surface of concrete are different, a temperature gradient will be formed, resulting in temperature stress and temperature deformation. When this temperature stress exceeds the internal and external constraint stress of concrete (including the tensile strength of concrete), cracks will occur, and it is preliminarily judged that cracks are caused by excessive temperature stress.