This paper presents a verification of tensile strength and failure mechanism of internal diaphragms in wide flange (WF) beam-to-box column connections with and without concrete filling. The flexural load transfer mechanism from the beam flange to column was locally evaluated based on a plate-to-box column connection with an internal diaphragm. The objective of this study is to establish an efficient design method for the internal diaphragms in WF-beam-to-box column connections. First, theoretical and experimental approaches were used to evaluate a strength equation considering the effects of the plate-to-column width and column width-to-thickness ratios and concrete filling. Finally, the cyclic performance of the WF-beam-to-box column connections was numerically assessed to validate the design and response of the internal diaphragms. The results showed that concrete filling was able to improve the connection strength by approximately 30% compared to that without concrete filling. It was also confirmed that the plate-to-column width and column width-to-thickness ratios did affect the tensile strength of the connection and must be considered in the strength equation. More importantly, the response of an internal diaphragm designed using the proposed equation in this study was validated and confirmed by both the experiment and the numerical evaluation.

本文提出了在有或没有混凝土填充的宽法兰（WF）梁对箱柱连接中内部膜片的抗拉强度和破坏机理的验证。基于带有内部膜片的板对箱柱的连接，局部评估了从梁的凸缘到柱的弯曲载荷传递机制。这项研究的目的是为WF-梁到箱式色谱柱连接中的内部隔膜建立一种有效的设计方法。首先，使用理论和实验方法来评估强度方程，其中考虑了板柱宽度和柱宽厚度比以及混凝土填充的影响。最后，通过数值评估了WF梁到箱式色谱柱连接的循环性能，以验证内部隔膜的设计和响应。结果表明，与不填充混凝土相比，混凝土填充能够将连接强度提高约30％。还可以确定，板宽比和柱宽比确实影响了连接的拉伸强度，因此必须在强度方程中加以考虑。更重要的是，通过本实验和数值评估，均验证并确认了使用本文提出的方程式设计的内部隔膜的响应。