钢筋与混凝土粘结强度的理论计算与试验研究

对未配箍筋的拉拔试件,基于Tepfers受均匀内压作用的厚壁圆筒力学模型,建立了钢筋与混凝土间粘结强度的理论分析模式。在计算粘结强度的表达式中不仅考虑了变形钢筋与混凝土间的机械咬合作用,而且考虑了两者间的摩擦作用。对配箍筋的拉拔试件,分析了构件达到极限承载力时粘结强度的计算模式和箍筋发挥作用的程度,得到了箍筋的最大应变值。同时进行了高性能混凝土与钢筋的粘结性能试验研究,得到的理论值与试验值吻合良好。

Theory and Test on Computative Model of Local Bond Strength Between Reinforcing Bars and Concrete

To obtain the computative model of local bond stress between reinforcement and concrete, Tepfer's partly cracked thick cylinder model is modified. The new computative model concludes not only the mechanical interaction but also the frictional action that is rarely considered before. However, the frictional action plays an important role in the bond stress in the working load stage as well as at collapse. The new computative model may be more reasonable.The effect of stirrups is considered. The experiments on bond stress of short length specimens made of high performance concrete (HPC), is also reported. The results coincide with those of the calculation.