钢筋混凝土板等效导热系数理论计算公式  

Theoretical Calculation Formula of Equivalent Thermal Conductivity for Reinforced Concrete Slab

作　　者：张晨晨 王亚红[1] 李宗利[1] ZHANG Chen-chen;WANG Ya-hong;LI Zong-li(Institute of Soil and Water Conservation,Northwest A&F University,Yangling 712100,China)

机构地区：[1]西北农林科技大学水利与建筑工程学院,陕西杨凌712100

出　　处：《水电能源科学》2024年第12期92-95,100,共5页Water Resources and Power

摘　　要：钢筋混凝土结构属于一种复合材料,其导热性能受配筋率、钢筋方向等因素影响。将钢筋混凝土板视为钢筋与混凝土组成的两相复合材料,基于串、并联等效模型,并借鉴分层组合式有限元模型中的钢筋层假设,得到不同热流方向的等效导热系数计算公式。通过试验验证了该公式的合理性;同时,分析了钢筋走向、配筋率、板厚、混凝土与钢筋导热系数比值等因素对钢筋混凝土板导热系数的影响规律。研究表明,建立的等效导热系数计算值与试验结果吻合较好。钢筋混凝土板三个方向的等效导热系数随配筋率的增大而增大,对钢筋轴向等效导热系数影响最显著;相同配筋情况下,垂直钢筋轴向另两个方向的等效导热系数均随混凝土与钢筋导热系数比值增大而增大,钢筋轴向等效导热系数随板厚增大而增大,板厚对其他两个方向等效导热系数几乎不影响。所建立的等效导热系数计算公式可将钢筋混凝土板等效为均质材料,以简化热传导分析。Reinforced concrete structure is a kind of composite material,and its thermal conductivity is affected by factors,such as reinforcement ratio and steel bar direction.The reinforced concrete slab was regarded as a two-phase composite material composed of steel bar and concrete.Based on the series and parallel equivalent models and referred to the reinforcement layer hypothesis in the layered combined finite element model,the calculation formulas of equivalent thermal conductivity in different heat flow directions were obtained.The rationality of the formula was verified by experi-ments.The effects on equivalent thermal conductivity of the orientation of reinforcing bars,reinforcement ratio,slab thickness,and the ratio of thermal conductivity between concrete and steel on the thermal conductivity of reinforced con-crete slabs were analyzed.It is shown that the results of the equivalent thermal conductivity is well agreed with result of the experimental.The equivalent thermal conductivity of reinforced concrete slab in three directions increases with the in-crease of reinforcement ratio,and the influence on the axial equivalent thermal conductivity of steel bar is the most signifi-cant.In the case of the same reinforcement,the two equivalent thermal conductivity coefficients perpendicular to the axial direction of the steel bar increase with the increase of the ratio of thermal conductivity between concrete and steel.The e-quivalent thermal conductivity of the steel bar increases with the increase of the plate thickness,and the increase of the plate thickness has little effect on the equivalent thermal conductivity in the other two directions.The established equiva-lent thermal conductivity calculation formula can be equivalent the reinforced concrete slab to the homogeneous material for simplifying the heat conduction analysis.

关 键 词：钢筋混凝土板 等效导热系数 钢筋层等效 配筋率 钢筋走向 

分 类 号：TV332[水利工程—水工结构工程]