Zhou Fengli, Liang Huaping, Jiang Jinlong, Zhou Zhixiang, Zou Yang
School of Civil Engineering, Chongqing Jiaotong University, Chongqing, 400074, People's Republic of China.
State Key Laboratory of Mountain Bridge and Tunnel Engineering, Chongqing Jiaotong University, Chongqing, 400074, People's Republic of China.
Sci Rep. 2025 Mar 31;15(1):10993. doi: 10.1038/s41598-024-82933-3.
Stud connectors are widely used to realize the shear connection of steel girders and prefabricated bridge decks in prefabricated steel-concrete composite beams. However, the dense arrangement of stud connectors in the combined bending and shear region makes fabricating prefabricated bridge decks difficult and weakens their integrity. Therefore, a novel prefabricated steel-concrete connector (PSCC) is proposed to accelerate the prefabrication and construction of prefabricated steel-concrete composite bridges. To validate the mechanical properties of PSCC connectors, four groups of 11 static push-out specimens were tested to analyze the effect of interfacial defects and different concrete materials for the shear performance of PSCC connectors. The PSCC connectors have high shear stiffness and ductility. At load levels up to 0.9Pu, the slip values of PSCC connectors range from 6.74 mm to 11.72 mm, which specifies a minimum slip of 6 mm (EC4). The shear capacity of the specimens with 30% and 60% interface defect areas decreased by 0.39% and 8.91%, respectively, compared to the specimens with no interface defects. When the connection layer material was replaced from ordinary concrete to UHPC, the shear capacity of PSCC connectors increased by 39%, and the failure mode shifted from shear failure of studs to shear failure of reinforcements. Moreover, cyclic loading marginally enhanced the shear capacity of PSCC connectors, serving as a safety reserve in practical engineering. Finally, a shear capacity calculation formula for PSCC connectors, derived from finite element analysis and existing formulas, achieved a prediction accuracy within 6.2%.
栓钉连接件广泛应用于装配式钢 - 混凝土组合梁中钢梁与预制桥面板的抗剪连接。然而，在弯剪组合区域栓钉连接件的密集布置使得预制桥面板的制造困难，并削弱了其整体性。因此，提出了一种新型的装配式钢 - 混凝土连接件（PSCC），以加快装配式钢 - 混凝土组合桥梁的预制和施工。为验证PSCC连接件的力学性能，对四组共11个静力推出试件进行了试验，以分析界面缺陷和不同混凝土材料对PSCC连接件抗剪性能的影响。PSCC连接件具有较高的抗剪刚度和延性。在荷载水平达到0.9Pu时，PSCC连接件的滑移值在6.74 mm至11.72 mm之间，满足欧洲规范4（EC4）规定的最小滑移6 mm。与无界面缺陷的试件相比，界面缺陷面积为30%和60%的试件抗剪承载力分别降低了0.39%和8.91%。当连接层材料从普通混凝土替换为超高性能混凝土（UHPC）时，PSCC连接件的抗剪承载力提高了39%，破坏模式从栓钉的剪切破坏转变为钢筋的剪切破坏。此外，循环加载略微提高了PSCC连接件的抗剪承载力，可作为实际工程中的安全储备。最后，基于有限元分析和现有公式推导得出的PSCC连接件抗剪承载力计算公式，预测精度在6.2%以内。
