| 摘要: |
| 采用防护热板法和瞬态平面热源法测试了粗骨料、水泥砂浆和混凝土的导热系数，考察了砂率、骨料种类及其体积分数、水灰比和饱和度对混凝土导热系数的影响；利用复合材料导热系数模型，分析了饱和/干燥状态下混凝土内水泥砂浆与粗骨料间界面热阻的影响.结果表明：混凝土导热系数随饱和度、骨料体积分数、骨料导热系数的增大而增加，随水灰比的增大而减小；对干燥混凝土导热系数的预测需考虑界面热阻的影响.在假定混凝土固相导热系数随着饱和度线性增大的基础上，提出了基于饱和度影响的混凝土导热系数计算模型. |
| 关键词: 混凝土 导热系数 复合材料 试验研究 预测模型 |
| DOI：103969/jissn1007 9629201502001 |
| 分类号: |
| 基金项目:国家高技术研究发展计划（863计划）项目（2012AA050903） |
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| Experimental Study and Prediction Model of Thermal Conductivity of Concrete |
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ZHANG Weiping, TONG Fei, XING Yishan, GU Xianglin
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Department of Architectural Engineering, Tongji University, Shanghai 200092, China
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| Abstract: |
| Thermal conductivity of coarse aggregate, cement mortar as well as concrete were measured by the method of guarded hot plate apparatus and transient plane source. The influences of sand ratio, type and volume fraction of aggregate, water cement ratio and saturation degree were investigated. By use of the theoretical models for thermal conductivity of composite materials, interfacial thermal resistance between cement mortar and coarse aggregate in saturated and non saturated concrete were studied. The results show that thermal conductivity of concrete increases with the increment of saturation degree of concrete, volume fraction and thermal conductivity of aggregate, while decreases with the water cement ratio. The interfacial thermal resistance cannot be neglected for dry concrete. Finally, assuming that the thermal conductivity of solid phase in concrete increases linearly with saturation degree, a prediction model was proposed for thermal conductivity of concrete in consideration of saturation degree. |
| Key words: concrete thermal conductivity composite material experimental study prediction model |
