In this study, seismic bi–axially loaded RC beam–column joints are investigated. An experimental campaign on shear–critical corner joints is presented, including two as–built specimens and one retrofitted using fully–fastened–haunches (FFHR). Bi–axial tests adopted hexagonal protocol which is essentially to apply load in one direction double with respect to the other. Results obtained for as–built condition were included in a database of corner joints tested bi–axially and discussed in the light of the impact of bi–axial load on joint’s shear strength. Further, non–linear finite elements were employed to thoroughly evaluate the bi–axial response. Haunch retrofit was capable to reduce both shear stresses and distortion at joint. Experimentally–derived internal forces were used to validate three–dimensional Strut-and-Tie model of the joints. Such design tool is recommended for practice cases adopting FFHR.

在本研究中，研究了地震双轴加载 RC 梁柱节点。提出了一项关于剪切临界角接头的实验活动，包括两个竣工样本和一个使用完全紧固腰部（FFHR）进行改造的样本。双轴测试采用六边形协议，本质上是在一个方向上相对于另一个方向施加双倍的载荷。竣工条件获得的结果包含在双轴测试角接头的数据库中，并根据双轴载荷对接头剪切强度的影响进行讨论。此外，采用非线性有限元来彻底评估双轴响应。腋部改造能够减少接头处的剪切应力和变形。实验得出的内力用于验证接头的三维支柱和拉杆模型。建议将此类设计工具用于采用 FFHR 的实践案例。