温度突降条件下大体积混凝土表层温度计算

Calculation of surface-layer temperature of mass concrete under temperature sudden drop

分析周期温度边界与任意温度边界条件下大体积混凝土温度计算的现有方法;提出寒潮袭击下混凝土表层温度计算的新方法.在无限平面模型能够成立的临界时间内,给出大体积混凝土表层温度的显示表达;讨论与之相关的寒潮扰动深度、等效厚度、表面保护作用等问题,并以室外试验成果说明该方法可为研究大体积混凝土受寒潮袭击时表面开裂问题和表面保护设计提供支持.

The prevailing methods to analyze the temperature of concrete under arbitrary convection boundary are summarized. By superposition theory, a new approach, which focuses on the surface-layer temperature of mass concrete, is presented, in which the air temperature is dispersed as a series of linear processes. Taking the advantages of delay characteristics of thermal conductivity of concrete, a simple expression to calculate surface temperature for semi-infinite model is given; provide that the time is limited in the critical range which controls the disturbed depth into concrete. Some problems involved in temperature calculation, such as the disturbed depth, the effect of surface protection, as well as critical time are discussed. The new method mentioned above may be as a basement to study the surface cracking of mass concrete.