高强度砂浆群钉连接件抗剪承载力试验

Shear Capacity of Grouped Stud Connector Embedded by High Strength Mortar

摘要:

在混凝土桥面板预留孔浇筑高强度砂浆包裹群钉连接件以实现钢梁与混凝土有效结合.为了得到高强度砂浆包裹的焊钉的剪切强度及分析不同群钉布置形式对抗剪承载力的影响，进行了1组单钉基本力学试验和5组不同群钉布置形式的焊钉力学性能试验.试验结果表明：采用高强度砂浆包裹焊钉的连接方式可靠，焊钉具有较高的抗剪强度, 单钉承载力平均值为197.2 kN.在群钉连接件中不同的焊钉布置方式对承载力有一定影响，总体上随焊钉数量的增多，平均的单钉承载力呈下降趋势，焊钉数量最多的NS25试件，其平均单钉承载力为160kN，为单钉推出试验值的81%.此外，根据多排焊钉的荷载滑移曲线，给出了多排焊钉的荷载滑移关系表达式，与试验结果比较表明，所给表达式的结果与试验结果吻合较好.

关键词:剪力钉连接件; 推出试验; 群钉; 高强度砂浆; 抗剪强度

Abstract:

Using the high strength mortar to pour into the hole prepared in the concrete bridge deck to fulfill the effective connection of steel girder and concrete. The shear bearing capacity of single stud obtained from single row stud push out test and that from multi row stud push out test are different in some degree. In order to test the shearing strength of the studs wrapped by the high strength mortar and compare the influence of group studs layout form on its shear strength, one group of single stud specimen and five groups specimens with different studs layout were carried out. The test results show that the connecting method by wrapping the studs with high strength mortar is reliable, and the shearing strength of the studs is high, and the average capacity of single stud is 197.2 kN. There are some influences on the shearing capacity of different group studs layout form. With the increase of stud row number the average single stud shear capacity is decline. The specimen N25 with the maximum stud numbers has the average single stud shear capacity of 160kN, which is 81% of the capacity of the single stud test. According to the load slip curves of multi row stud, the expression of load slip relation of multi row stud is proposed. Compared to testing results, the expression has a better match with the experimental values.

Key words:stud shear connector; push out test; group studs; high strength mortar; shearing strength