Sheet piles are used in various construction field applications, such as retaining walls, slope reinforcement, breakwaters, and ports, owing to their excellent strength, light weight, waterproofing, durability, and workability. The U-type section steel piling, which is a type of sheet pile, is composed of hollow trapezoidal sections with interlocks at both ends. At the construction site, a structure is formed by assembling the interlocks of each cross-section in a simple fitting type using the driving or indentation method. Interlock is an important part of connecting steel sheet piles. The shape, size, and steel type in the interlock affect the connection quality and structural performance of the structure. In this study, tensile tests were performed on test specimens connected in series in a simple fitting type for the interlock, which is an important component of the U-type section steel piling. It was observed that the load–displacement relationship temporarily decreased and then increased. In addition, formula for calculating the maximum strength of interlock was discussed and the predictions were compared with the experimental results, and the high consistency of the formula was verified.

板桩因其优异的强度、轻质、防水、耐用和可加工性而被广泛应用于挡土墙、边坡加固、防波堤和港口等各种建筑领域。U型型钢桩是板桩的一种，由两端互锁的空心梯形截面组成。在施工现场，通过使用打入或压入方法将各截面的互锁件以简单的配合方式组装而成结构。联锁是连接钢板桩的重要组成部分。联锁中的形状、尺寸和钢材类型影响着结构的连接质量和结构性能。在本研究中，对以简单配合类型的联锁串联连接的测试样本进行拉伸测试，是U型型钢桩的重要组成部分。据观察，载荷-位移关系暂时减小，然后增大。此外，讨论了互锁最大强度的计算公式，并将预测结果与实验结果进行了比较，验证了公式的高度一致性。