为了揭示型钢高强混凝土界面黏结传力机理,以混凝土强度、横向配箍率、保护层厚度、型钢锚固长度和抗剪件设置部位为变化参数,设计12个试件进行静力推出试验,观察试件的受力破坏过程及裂缝发展形态,获取各试件加载端和自由端的荷载-滑移全过程曲线,基于试验结果对型钢高强混凝土界面黏结传力机理进行了详细阐述,并对各变化参数的影响规律进行了深入分析,最后对型钢高强混凝土界面黏结强度计算方法进行了探讨,并提出其实用计算方法.研究结果表明:适当增大截面的横向配箍率和混凝土保护层厚度,能有效提高型钢高强混凝土的界面黏结强度;当型钢锚固长度满足一定值后,增大锚固长度对提高极限黏结强度并不明显;对高强混凝土而言,随着混凝土强度等级的提高,界面极限黏结强度却有所降低;通过设置抗剪件的方法能有效提高界面黏结传力性能;型钢高强混凝土界面黏结传力的组成中,化学胶结力占比重最大,摩擦力次之,机械咬合力最小.%In order to reveal the interface bond force transfer mechanism between shape steel and high-strength concrete,concrete compressive strength,concrete cover thickness,shape steel embedment length,transverse stirrup ratio and layout of shear stud were considered as variable parameters,12 steel reinforced high-strength concrete specimens were designed and quasi-static push-out testing was conducted.Failure process and crack propagation of specimens were observed,load-slip curves of free end and loading end of specimens were obtained,the interface bond transfer mechanisms between shape steel and high-strength concrete was expounded according to test results,the influencing rules of each factor to bond slip performance were elaborately analyzed,some related computational formulas of bond strength were discussed and the utility formulas were put forward.The key results show:Interface ultimate bond strength could be increased to some extension by increase transverse stirrup ratio and concrete cover thickness;The relationship between shape steel embedment length and ultimate bond strength are not significant once shape steel embedment length reaches a certain value;For the high-strength concrete,the ultimate bond strength may be reduced to some degree along with the increase of concrete-strength;Bond slip performance could be effectively improved by setting up shear stud;The largest proportion of bond force is chemical bond force,frictional fore is smaller and bite force is the smallest.
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