桥塔钢-混结合段剪力连接件承载力试验研究

Test Study of Bearing Capacity of Shear Connectors Used for Steel and Concrete Composite Segment in Bridge Pylon

为确保斜拉桥桥塔钢-混结合段连接的安全可靠，应选择合适的剪力连接件。结合连岛工程跨海斜拉桥索塔锚固区的设计，比较不同极限承载力公式的差异。对栓钉连接件进行模型试验研究，试验得到栓钉的荷载～滑移量曲线。重点研究栓钉的抗剪承载力及破坏形态等，并将试验结果与所有公式的计算结果进行比较。试验结果表明：栓钉连接件以栓钉受弯剪破坏为主，具有良好的延性，在破坏前有明显的屈服过程。在承载力方面，群钉试验得到的用于桥塔钢-混结合段的单钉极限承载力平均比《钢结构设计规范》（GB50017—2003）的计算值高32％左右。

To ensure the safe and reliable connection of the steel and concrete composite segment in pylon of cable-stayed bridge, the appropriate shear connectors should be chosen. With reference to the design of the cable-to-pylon anchor zone of a cable-stayed sea-crossing bridge of a island link project, the differences of the formulas for calculation of the ultimate bearing capacity of the connectors were compared. The model tests for the stud connectors were made and the load -slip curves of the connectors were obtained. The shearing capacity and failure modes of the connectors were studied in detail and the results of the tests were compared to the those calculated by the different formulas. The results of the tests show that the bending and shearing is the major failure form of the stud connectors, the connectors have good ductility and have no evident yielding before failure. In aspect of the bearing capacity, the ultimate bearing capacity of a single stud connector used for the steel and concrete composite segment in pylon obtained from the tests for the group stud connectors is averagely about 32% higher than the values calculated according to the Code for Design of Steel Structures （GB 50017-2003）.