超细晶粒钢筋粘结锚固性能的试验研究

通过对48个超细晶粒钢筋粘结锚固试件的拉拔试验,对超细晶粒钢筋的粘结锚固性能进行了全面研究.在试验的基础上对超细晶粒钢筋的粘结强度进行了分析计算,并给出了粘结锚固长度的取值建议.研究结果表明,虽然超细晶粒钢筋属推广的新型工程材料,轧制工艺与传统钢筋不同,但超细晶粒钢筋的粘结锚固性能与普通热轧带肋钢筋(月牙纹)基本相同,其设计锚固长度la仍可按现行《混凝土结构设计规范》GB50010-2002规定的公式计算;另外考虑到近年来高强混凝土的应用日益增多,且当混凝土强度等级为C40~C80时,现行规范的设计锚固长度计算公式仍能较好适用于超细晶粒钢筋,建议锚固长度计算公式中混凝土强度等级的上限可提高到C60.

Experimental Investigation of Bond- anchorage Properties of Ultra -fine Grain Steel Bar

Based on 48 ultra-fine grain steel bars pull-out test,this paper investigates into the bond-anchorage properties of ultra-fine grain steel bars.Then the calculating formula of bond strength has been established on the tests,and the anchoring length of ultra-fine grain steel bars in the design of concre elements is proposed too.The result is that the bond-anchorage property of ultra-fine grain steel bar is identical to that of common crescent ribbed bar,the anchoring length can be designed with the formula in code for design of concrete structures(GB50010-2002).Considering the wider use of high-strength concrete in civil engineering of china today,it is proposed that the upper limit of class of concrete strength in formula should be updated to C60.