人工气候下混凝土温度响应规律与预计模型

Response Laws and Prediction Model of Temperature Change in Concrete in a Controlled Climate

通过人工气候环境的温度控制,研究混凝土内温度响应规律和预计模型.在建立混凝土内温度响应的理论预计模型基础上,开展混凝土升温、降温的响应规律试验研究,通过对混凝土内部温度的实时测量,得出混凝土内部一定深度位置处温度的响应曲线;开展对不同组成混凝土的导热系数测定试验.结果表明:恒定的人工气候环境下,混凝土内温度需要一定时间才能达到与环境温度一致,而且混凝土内温度均在初期响应较快;混凝土导热系数受混凝土水灰比和含水率的影响明显,且影响规律基本服从线性关系.通过理论预计和试验实测的响应曲线比较,证明本文的混凝土温度响应预计模型是可行的.

An artificial climate environment was used to control the temperature of instrumented concrete specimens. The response of the concrete to heating and cooling was studied experi- mentally by measuring the temperature at fixed positions in the specimens. The thermal con- ductivity of the concrete was determined at the same time. The experimental observations are compared to a predictive model. The results show that the times for the temperature to equili- brate with ambient temperature vary with the specimen. The thermal properties of the concrete change as the concrete ages. The thermal conductivity of the material is strongly influenced by both water cement ratio and the total water content of the concrete. The effect of these varia- bles follows a linear relationship. By comparing the theoretically predicted response curves to the experimentally derived ones it was possible to prove the reliability of the predictive model.