二维散热条件对混凝土内部温度梯度及热传输的影响

n the early hydration processes of concrete, surface radiating has important effects on the internal temperature distribution in concrete. In order to know the internal temperature distribution under the two-dimensional heat radiating, the temperatures and their changes were measured from the peak hydration temperature within different positions in concrete specimen. Results showed that under the condition of two-dimensional heat radiating, inner temperatures in concrete were affected by two directions. It was known that where closer to the surface had faster temperature declining with time went by, which brought out greater temperature differences between inside and outside. Consequently, greater temperature gradient and temperature stress came out. In rapid cooling stage, when was from final set to 60 hours, concrete cooled faster, which caused greater temperature stress. Under the condition of two-dimensional heat radiating, heat transferred faster from more interior position to more external than form the position where closer to surface to outside and radiated into environment. Near the surface in early stage, the temperature gradient could reach 80℃/m, as while as the internal temperature gradient could either reach 50 ℃/m.