纤维增韧混凝土与钢筋的粘结性能研究

The bond properties between fiber reinforced concrete and deformed bar

本文主要研究高性能混凝土中分别添加钢纤维或聚丙烯纤维后对其与钢筋粘结性能的影响,并与未添加纤维的高性能混凝土进行了比较。进行了三种类型的高性能混凝土与变形钢筋的粘结性能试验,以研究粘结强度、粘结本构关系的变化情况。试验结果表明高性能混凝土中添加0.5%(体积比)的钢纤维对极限粘结强度略有提高,峰值粘结应力对应的滑移有较大的增长;高性能混凝土中添加0.2%的聚丙稀纤维后极限粘结强度略有降低,峰值粘结应力对应的滑移亦略有减小。根据试验结果,给出了三种类型的高性能混凝土与钢筋的粘结本构关系的经验表达式。

In this paper the bond properties and bond constitutive relationships of three kinds of high performance concrete (HPC)and deformed bar had been researched. There were 12 axial pull out specimens. The experimental results indicated that when 0.5%(volume fraction) steel fibers were added to HPC, the ultimate bond stress was improved and the corresponding slip was also increased. The ductility of bond was improved as well. However, when 0.2%polypropylene fibers was added to HPC, the ultimate bond stress as well as the corresponding slip were all slightly reduced. Based on experimental results the empirical expressions of the bond constitutive relationships of three kinds of HPC are presented.