高温下混凝土界面抗剪性能研究

Study on the Shear Performance of Concrete at High Temperature

为研究预制装配式混凝土结构中混凝土界面在高温下的抗剪性能,分别对界面未植筋与界面植筋两类"Z"形试件进行了不同温度作用下(常温、200℃、400℃、600℃)的推出试验。对试件剪切破坏过程进行了模拟,通过双线性内聚力(Cohesive)模型分析了混凝土界面的粘结作用。结果表明:未植筋界面试件剪切破坏形式呈脆性破坏,界面植筋试件为延性破坏;随着温度的升高,混凝土界面的抗剪承载力降低,试件荷载-滑移曲线趋于平缓;采用内聚力模型可以较好地反映界面工作性能。

In order to study the shear resistance of concrete interface at high temperature in prefabricated concrete structure, two kinds of ＂Z＂ shaped specimens with interface without reinforcement and interface reinforcement were tested under different temperatures（normal temperature, 200℃, 400℃, 600℃）.The shear failure process of the specimen is simulated, and the cohesive effect of the concrete interface is analyzed by the bilinear cohesive force model.The results show that the shear failure mode of the specimen without reinforcement is brittle, and the interfacial reinforcement is ductile. With the increase of temperature, the shear strength of the concrete interface is reduced and the load slip curve of the specimen tends to be slow, and the cohesive model can better reflect the working properties of the interface.