Ultimate Strength Of Gusset Plate Of Steel Tubular With Gusset Plate Connections

Featured with good mechanical behavior，high reliability，good overall stability,steel tubular tower is applied widely in UHV transmission lines. The node employstube-gusset joint as the connection form in steel tubular tower. As the key component,the nodes, with a relatively complex force, are the focus of this study. Since thetube-gusset joint are used more and more widely, the mechanical behavior for the gussetplate should be researched as soon as possible. It has a great significance to analyze anddetermine the failure mode, failure reasons and factors in the complex forces andlarge-scale load state, which can provide very useful advices to the design andstructural measures of transmission tower in future. On this basis, the ultimate strengthof tube-gusset joint was explored primarily and the following researches are performedin this paper:Firstly, conduct experimental research with Huainan (city in Anhui Province) toShanghai1000kV power transmission project. Since full-scale reflects the experimentresults more truly and accurately than reduced scale experiment, four groups offull-scale components are adopted for the static monotonic loading tests. By observingthe failure phenomena in the test, the load-out-of-plane displacement curves and theload-micro stain of plate curves are obtained, and the failure mode are analyzed basedon experiment data.Secondly, establish finite element models. Analyze the pressure ultimate strengthvia the finite element and experimental calculation, thus it can be obtained that there aretwo kinds of failure models as overall buckling destruction and local bucklingdestruction. The main parameters which affect the ultimate, such as the gusset platethickness, non-limb length, bolt hole spacing and arrangement and conformation of theplate are proposed and analyzed. As a result, two forms, adding rib at gusset center andusing the cross-shaped gusset plate, can modify the failure mode and the invalidationavenue, which can greatly help to improve the pressure ultimate strength for thegusset plate.Thirdly, based on the experimental result and the finite element theoretical analysisresult, calculation formula used for the tube-gusset joint plate under the pressureultimate strength is summed up. It has a practical significance, for it can provide veryuseful comments and suggestions for future transmission tower design patterns and structural measures.