除锈方法对钢筋与混凝土粘结性能的影响试验研究

Experimental study on the effect of rust removal methods on the bonding performance between steel bar and concrete

对直径14mm和18mm的变形钢筋进行不同程度的锈蚀作用,然后选用角磨机、除锈剂和抛丸机三种方法进行除锈,并利用除锈后的钢筋制作中心拔出试件,对不同钢筋直径、不同锈蚀率和不同除锈方法得到的钢筋和混凝土的粘结性能进行试验研究。试验过程中观察记录了加载荷载、钢筋滑移量、峰值荷载、试件破坏形式和裂缝发展情况等。根据试验结果分析了钢筋直径、锈蚀率和除锈方法对钢筋和混凝土的极限粘结应力、峰值滑移量的影响。试验结果表明:直径14mm的钢筋角磨机除锈后发生劈裂破坏,除锈剂和抛丸机除锈后发生拔出破坏;直径18mm钢筋都发生劈裂破坏;随着锈蚀率的增大,除锈后试件的极限粘结应力减小,峰值滑移量增大。

The deformed steel bars with diameters of 14mm and 18mm were subjected to different degrees of corrosion,and then the angular mill,derusting agent and shot blasting machine were used to remove the corrosion.The specimens were pulled out from the center of the derusted steel bars,and the bonding properties of the steel bars and concrete obtained by different diameters of steel bars,different corrosion rates and different derusting methods were experimentally studied.During the test,loading load,steel bar slippage,peak load,specimen failure mode and crack development were observed and recorded.According to the test results,the effects of reinforcement diameter,corrosion rate and derusting method on the ultimate bond stress and peak slip of reinforcement and concrete were analyzed.The test results show that the steel bars with diameters of 14mm have splitting failure after derusting by the angular mill,and have pull-out failure after derusting by the derusting agent and shot blasting machine.The steel bars with diameters of 18mm have splitting failure.With the increase of corrosion rate,the ultimate bond stress of specimens after derusting decreases,and the peak slip increases.