Cold-formed steel (CFS) sections can be designed in many configurations and, compared to hot-rolled steel elements, can lead to more efficient and economic design solutions. While CFS moment resisting frames can be used as an alternative to conventional CFS shear-wall systems to create more flexible space plans, their performance under strong earthquakes is questionable due to the inherited low local/distortional buckling of thin-walled CFS elements and limited ductility and energy dissipation capacity of typical CFS bolted-moment connections. To address the latter issue, this paper presents a comprehensive parametric study on the structural behaviour of CFS bolted beam-to-column connections with gusset plates under cyclic loading aiming to develop efficient design solutions for earthquake resistant frames. To simulate the hysteretic moment–rotation behaviour and failure modes of selected CFS connections, an experimentally validated finite element model using ABAQUS is developed, which accounts for both nonlinear material properties and geometrical imperfections. Connection behaviour is modelled using a connector element, simulating the mechanical characteristics of a bolt bearing against a steel plate. The model is used to investigate the effects of bolt arrangement, cross-sectional shape, gusset plate thickness and cross-sectional slenderness on the seismic performance of CFS connections under cyclic loading. The results indicate that, for the same amount of material, folded flange beam sections with diamond or circle bolt arrangements can provide up to 100% and 250% higher ductility and energy dissipation capacity, respectively, compared to conventional flat-flange sections with square bolt arrangement. Using gusset plates with the same or lower thickness as the CFS beam may result in a premature failure mode in the gusset plate, which can considerably reduce the moment capacity of the connection. The proposed numerical model and design configurations can underpin the further development and implementation of CFS bolted-moment connections in seismic regions.

冷弯型钢（CFS）型材可以设计成多种构造，与热轧钢元件相比，可以提供更有效，更经济的设计解决方案。尽管CFS抗弯框架可以用作常规CFS剪力墙系统的替代方案以创建更灵活的空间计划，但是由于薄壁CFS元件固有的低局部/变形屈曲和延展性有限，它们在强地震下的性能值得怀疑和典型的CFS螺栓矩连接的能耗。为了解决后一个问题，本文针对循环荷载作用下具有角撑板的CFS螺栓连接的梁到柱连接的结构性能进行了全面的参数研究，旨在开发抗震框架的有效设计解决方案。为了模拟所选CFS连接的滞后力矩-旋转行为和破坏模式，开发了使用ABAQUS进行实验验证的有限元模型，该模型考虑了非线性材料特性和几何缺陷。使用连接器元件对连接行为进行建模，模拟连接到钢板的螺栓轴承的机械特性。该模型用于研究在循环荷载下螺栓布置，横截面形状，角撑板厚度和横截面细长度对CFS连接抗震性能的影响。结果表明，对于相同数量的材料，采用菱形或圆形螺栓布置的折叠式法兰梁截面可以分别提供高达100％和250％的更高的延展性和能量耗散能力，与传统的方法兰布置的扁平法兰型相比。使用厚度等于或小于CFS梁的角撑板可能会导致角撑板过早失效，这会大大降低连接的抗弯能力。所提出的数值模型和设计配置可为地震区域CFS螺栓矩连接的进一步开发和实施提供基础。