Steel connections are designed with components such as bolts, plates, and welds. The proof of the plates loaded in-plane can be made by hand calculations or more realistic with a nonlinear FE-simulation. As an alternative method, a modified version of the discontinuity layout optimization (DLO) procedure is presented in this paper. The modification takes yield zone mechanisms into account. Furthermore, a compression-only contact was implemented to reproduce the bearing behaviour of bolted connections. The DLO procedure was tested on tensile specimens with and without bolts. The obtained collapse mechanisms and ultimate loads were compared to results from the Eurocode EN 1993-1-8, literature, and FE-simulations. Recommendations to the correct discretization of the tested specimens were given. Especially for the bearing behaviour, modification factors, based on a parameter study, were worked out. The DLO procedure reproduced the collapse loads and mechanisms of all considered cases correctly. The obtained bearing capacities are, in most cases, conservative compared to the Eurocode EN 1993-1-8. The presented research can be seen as the basis for future investigations on more complex problems in steel connections.

中文翻译：

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不连续布置优化在钢件和单螺栓钢连接件中的应用

钢连接设计有螺栓、板和焊缝等组件。可以通过手工计算或更逼真的非线性有限元模拟来证明平面内加载的板。作为替代方法，本文介绍了不连续布局优化 (DLO) 程序的修改版本。修改考虑了屈服区机制。此外，还实施了仅压缩接触以重现螺栓连接的轴承行为。DLO 程序在带螺栓和不带螺栓的拉伸试样上进行了测试。将获得的倒塌机制和极限载荷与欧洲规范 EN 1993-1-8、文献和有限元模拟的结果进行比较。给出了对测试样本的正确离散化的建议。特别是对于轴承行为，根据参数研究计算出修正因子。DLO 程序正确地再现了所有考虑案例的坍塌载荷和机制。与欧洲规范 EN 1993-1-8 相比，获得的承载能力在大多数情况下是保守的。所提出的研究可以看作是未来对钢连接中更复杂问题进行调查的基础。