长孔型开孔板连接件抗剪性能试验研究

Experimental investigation on shear behavior of long-hole perfobond connectors

为解决组合结构桥梁开孔板连接件孔间距或板高受限的设计难题,提出将开孔板圆孔单向拓展为长孔的钢与混凝土连接构造新型式;以圆孔孔径、抗剪纵向或横向的开孔幅度即孔长、孔高等为变化参数,进行7组共21个模型试件的抗剪推出试验,比较研究不同孔形开孔板连接件的抗剪承载力、刚度及变形性能。研究结果表明:开孔面积相同时,长孔型与圆孔型开孔板连接件的抗剪承载力相当;抗剪刚度随孔径或孔高增加而增大,不受孔长变化影响;与开孔面积相同的圆孔型开孔板连接件比较,长孔型开孔板连接件沿抗剪纵向拓孔时峰值滑移量大幅增大,横向拓孔时峰值滑移量减小;在正常使用极限状态下的残余滑移量较小,各孔型开孔板连接件均具有较好的变形恢复能力。

To solve the problem of designing perfobond connectors in composite bridges where hole distances or rib heights are limited,a new type of steel-concrete connection is proposed by lengthening circular holes of perfobond connectors. Shear push-out tests were conducted on 21 specimens in seven groups. The experimental parameters included the hole diameter,the hole length parallel to shear force,and the hole height perpendicular to shear force. The shear strength,shear rigidity and slip behavior of perfobond connectors with different hole geometries were compared and analyzed. The results indicate that the shear strength is equivalent for long-hole and circular-hole perfobond connectors when the hole area is equal. The shear rigidity increases with the hole diameter and the hole height,but keeps constant with the hole length. Compared with circular-hole perfobond connectors of the same hole area,the peak slip of longitudinal long-hole type increases substantially,while that of lateral long-hole type decreases slightly. No remarkable residual slip occurs in serviceability limit state,and all types of perfobond connectors can preferably recover from slip deformation.