GRC模板与混凝土界面黏结性能试验研究

Experimental study on the interfacial bonding performance of GRC formwork and concrete

通过设计8种类型的复合试件并进行推出剪切试验,研究不同混凝土强度、不同混凝土类型、不同GRC模板厚度以及GRC模板表面是否带肋等因素对GRC模板与混凝土界面黏结性能的影响。研究结果表明:随着中间混凝土强度的提高,复合试件的界面黏结强度增大,刚度变大,表现出更好的塑性变形能力;中间采用自密实混凝土对复合试件的界面黏结强度影响不大,但削弱了试件的变形能力;随着GRC模板厚度的增大,复合试件的界面黏结强度有一定的提高,但厚度超过一定范围后,复合试件由塑性破坏转化为脆性破坏;GRC模板加肋能显著提高复合试件的界面黏结强度,但变形能力降低,且只存在弹性变形阶段。通过对试验数据进行回归分析,提出了此类复合试件的界面黏结强度计算式。

The push-out shear test was carried out by designing 8 types of composite specimens and the influence of concrete strength,concrete types,the thickness of GRC formwork and whether the surface of the GRC formwork is ribbed on the interfacial bonding performance of BFRP reinforced composite cement plate and concrete was studied.The results show that with the increase of mid concrete strength,the interfacial bonding strength and stiffness of composite specimens increases,and shows better plastic deformation performance.The use of self-compacting concrete in the middle has little effect on the interfacial bonding strength of the composite specimen,but it weakens the deformation capacity of the specimen.With the increase of the thickness of the GRC formwork,the interfacial bonding strength of the composite specimen is improved,but after the thickness exceeds to certain range,the composite specimen is transformed from plastic fracture to brittle fracture.Add ribs to the GRC formwork can significantly improve the interfacial bonding strength of the composite specimen,but the deformation capacity decreases,and there is only elastic deformation stage.The formula for calculating the interfacial bonding strength of such composite specimens is proposed through the regression analysis of experimental data.