不锈钢筋与混凝土的黏结性能

Bonding Performance of Stainless Steel Bars and Concrete

为探讨不锈钢筋与混凝土的黏结力及分布,进行了不锈钢带肋钢筋、普通带肋钢筋与混凝土的平均黏结力、黏结力分布对比试验。不锈钢带肋钢筋、普通带肋钢筋与混凝土的平均黏结力试验表明,各种钢筋与混凝土的平均黏结应力都随着混凝土强度的增大而增大,钢筋强度对钢筋与混凝土的平均黏结应力影响不明显,说明不锈钢筋与混凝土的平均黏结应力与普通钢筋没有明显差别。不锈钢带肋钢筋、普通带肋钢筋与混凝土的黏结力分布试验表明,二者与混凝土的黏结应力分布规律相近,其黏结应力峰值出现在加载端附近;随着荷载的不断增大,应力峰值显著增大,但位置基本不变,有效黏结长度增加缓慢,仅在试样濒临破坏时,应力峰值才向自由端有些许移动。分析了两种钢筋与混凝土黏结的相似规律及存在的差异,提出了不锈钢筋应用于混凝土构件时初步的黏结力计算方法及构造措施。

In order to discuss the bonding force and distribution between stainless steel bar and concrete,the comparative test on the average bonding force,the bonding force distribution between ribbed stainless steel bar,ordinary ribbed steel bar and concrete is carried out. The test result of the average bonding forces between these ribbed steel bars and concrete shows that the average bonding forces between all kinds of steel bars and concrete increase with the increase of concrete strength,while the effect of the steel bar strength on the average bond stress between steel bar and concrete is not obvious,indicating that there is no significant difference between the average bonding stress of stainless steel bar and concrete and that of ordinary steel bar and concrete. The test result of the bonding force distribution between ribbed stainless steel bar,ordinary ribbed steel bar and concrete shows that（1） the distribution law of bonding stress between stainless steel bar and concrete is similar to that between ordinary steel bar and concrete,and the peak of the bonding stress appeares near the loading end;（2） with the constant increase of the load,the peak value of the stress increases,but the position is almost the same,and the effective bonding length increases slowly,the stresspeak moves to the free end slightly only when the specimen is near to failure. The similarities and differences of the bonding between the two kinds of bar and concrete are analyzed. The calculation method of initial bonding force and the construction measures for the stainless steel bar applied to the concrete members are put forward.