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镀锌截面适用于道桥工程、农业工程和建筑重建工程。镀锌截面用在结构工程中包括箱形框架、屋架、基础框架和构件之间的拉杆系统。这些结构在循环荷载作用下,容易产生疲劳破坏。在澳大利亚,镀锌截面(应用最广的是DuraGal)是壁厚小于4mm的薄壁截面。现在还没有针对厚度小于4mm截面的疲劳设计规程,而且现行的疲劳设计规程中也没有条文涉及到本文研究的井式梁连接。介绍了镀锌矩形中空截面和角钢组成的井式梁连接的疲劳试验。对两种类型的连接进行了分析,分别是矩形中空截面-矩形中空截面连接,以及矩形中空截面-角钢井式梁连接。井式梁的构造是将一个梁构件焊接在另一个梁构件的顶端而形成的。研究中通过对母材、焊缝、热影响区的硬化指数的静定来评价焊接质量,进而衡量热影响区产生裂纹的可能性对连接的应力集中系数的静定有助于确定热点区并且验证这些连接的裂纹发展模式。将从高周循环疲劳试验中得到的数据与现行疲劳设计曲线的数据进行对比。基于确定法和静力分析得到了井式梁连接的设计曲线。
Galvanized section suitable for bridge engineering, agricultural engineering and building reconstruction. Galvanized sections are used in structural engineering including box frames, roof trusses, base frames and tie rods between components. These structures are prone to fatigue failure under cyclic loading. In Australia, galvanized sections (DuraGal most widely used) are thin-walled sections with a wall thickness of less than 4 mm. There is no fatigue design protocol for sections less than 4 mm thick yet, and there are no provisions in existing fatigue design protocols that relate to the well-type beam connections studied in this paper. The fatigue test of well-type beam connection composed of galvanized rectangular hollow section and angle steel is introduced. Two types of connections were analyzed, namely a rectangular hollow section - rectangular hollow section connection, and a rectangular hollow section - angle steel beam connection. The well beam is constructed by welding one beam member to the top of the other beam member. In the study, the quality of welding was evaluated by the static analysis of the hardening index of the base metal, weld and heat-affected zone, and then the possibility of cracks in the heat-affected zone was evaluated. The static analysis of the stress concentration coefficient of the connection helped to determine the hotspot zone and Verify the crack propagation pattern for these connections. Compare the data from the high-cycle fatigue test with the data from the current fatigue design curve. Based on the deterministic method and the static analysis, the design curve of well beam connection was obtained.