基于基础容许温差的高寒地区大体积混凝土温控措施研究

Research on Mass Concrete Temperature Control Measures Based on the Basis Allowable Temperature Difference in Paramos

高寒地区在高温季节太阳辐射强,环境气温较高且昼夜温差大,对大体积混凝土的温控防裂极为不利。规范规定的基础容许温差是温控防裂设计中的一个重要的参考指标。鉴于此,依托西藏某实际工程,建立了三维有限元仿真模型,采用组合指数式水管冷却等效热传导法进行混凝土温度场仿真计算,基于基础容许温差对高寒地区高温季节温控措施进行分析。结果表明,即使是在高寒地区高温季节进行大体积混凝土施工时,混凝土受外界环境气温、太阳辐射和内部水化热影响依然很大,也需要采用骨料预冷和通水冷却等温控措施。

In paramos,solar radiation is strong,the environment temperature is high and temperature difference between day and night is large in high temperature seasons.It is harmful to temperature control and crack prevention for mass concrete.The basis allowable temperature difference regulated in standard is an important reference index in the design of temperature control.Therefore,a three-dimensional finite element simulation model is established based on a practical project in Tibet in this paper.To conduct concrete temperature field simulation calculation with cooling pipe equivalent model of the compound exponential formula.Then temperature control measures are analyzed based on the basis allowable temperature difference in high temperature seasons in paramos.Results show that,the effect of external environment temperature,solar radiation and hydration heat is still large for mass concrete construction even in high temperature seasons in paramos.The temperature control measures such as aggregate pre-cooling and water cooling are also needed.