冷轧带肋钢筋混凝土受弯构件疲劳性能的试验研究

Experimental research on fatigue behavior of concrete beams reinforced by cold-rolled deformed steel bar

对不同配筋率的冷轧带肋钢筋混凝土简支标准梁 (5 5 0mm× 1 5 0mm× 1 5 0mm)进行了等幅疲劳荷载试验研究 ,疲劳试验试件 60根 ,试件配筋率分别为 0 % ,0 2 9% ,0 487% ,0 93 4%和1 946% .这批试件的疲劳破坏形式为 :折断破坏、弯拉破坏和剪压破坏 .针对不同的疲劳破坏形式 ,分析了产生不同破坏形式的原因 ,提出了界限配筋率的概念 .受弯构件适当配置冷轧带肋钢筋不仅具有良好的抗裂性能和延性 ,而且其疲劳寿命也有显著的提高 .提出了考虑不同配筋率影响的。

Experiment of 60 simply supported concrete beams loaded by equal amplitude fatigue loading was studied. These beams were reinforced by cold-rolled deformed steel bar and were with different reinforcement ratio of 0%, 0.29%, 0.487%, 0.934% and 1.946%. The fatigue failure types of the beams were fracture failure, bending-tensile failure and shear-compression failure. Aimed at the different fatigue failure types of the beams, the failure causes are analyzed. A concept of critical reinforcement ratio is of fered. The concrete beams reinforced by adequate cold-rolled deformed steel bar have well resisting-crack ability and ductility, and their fatigue lives increase remarkably. A fatigue equation taken different rein forcement ratio into account is presented, which can be used for design of reinforced concrete pavement.