In order to improve the performance of wet joints in prefabricated ultra-high-performance concrete (UHPC) bridges, a comparative study was conducted to investigate the flexural behaviour of UHPC joint beams. Experimental tests were implemented on a complete beam and on five further specimens with, respectively, vertical joint, rhombus joint, vertical joint with strips, tied rhombus joint with strips, and welded rhombus joint with strips. The specimens’ failure modes, ultimate flexural capacities, strain distributions and load–deflection curves were investigated. The test results show that the flexural capacity of the joint beams is lower than that of the complete beam. Among the five specimens with wet joints, the welded rhombus joint with top and bottom strips had the greatest stiffness, the highest cracking resistance capacity, and the best flexural performance. From the best to the worst performing, the remainder of the wet joint specimens took the following order: the unwelded rhombus joint with strips, the vertical joint with strips, the rhombus joint and the vertical joint. In accordance with the test results and the related theoretical analysis, this paper proposes formulas to calculate the flexural capacity of the beam with UHPC joints.

中文翻译：

---

湿接缝超高性能混凝土梁抗弯性能试验研究

为了提高预制超高性能混凝土 (UHPC) 桥梁湿接缝的性能，进行了一项比较研究，以研究 UHPC 接缝梁的弯曲行为。实验测试在一个完整的梁和另外五个分别具有垂直接头、菱形接头、带条垂直接头、带条带的菱形接头和带条焊接菱形接头的试样上进行。对试样的破坏模式、极限抗弯能力、应变分布和载荷-挠度曲线进行了研究。试验结果表明，节点梁的抗弯承载力低于整梁的抗弯承载力。5个湿接头试件中，带顶底带的焊接菱形接头刚度最大，抗裂能力最高，和最佳的弯曲性能。从表现最好到最差，其余湿接头试样采用以下顺序：带条带的未焊接菱形接头、带条带的垂直接头、菱形接头和垂直接头。根据试验结果和相关理论分析，本文提出了UHPC节点梁抗弯承载力的计算公式。