【作者】 姚建岗；

【导师】 杨海旭；

【作者基本信息】 东北林业大学 ， 结构工程， 2011， 硕士

【摘要】 近年来,钢管结构体系得到了迅速发展。钢管板节点是钢管结构体系经常采用的(?)种节点形式。以往对管板节点承载力的研究主要集中在主管与板两侧相交的角点处破坏模式的研究,而对板的破坏模式研究较少。为了深入了解管板节点中节点板的受力性能、破坏形态及其受压极限承载能力等,本文以某超大直径凿井井架中的一个典型节点为基础,进行了相应的简化,以平面K型钢管板节点为研究对象,主要完成了以下工作：首先设计了节点试件,进行了节点的材性试验,为节点试验和数值模拟提供了相关参数。通过对节点的试验,研究了节点在荷载作用下应力的分布和发展规律：节点的塑性区首先出现在受压支管端部的两个角点,随后向受压支管两侧及端部发展,形成三个塑性区,最终在节点破坏前,三个塑性区连接为一体。节点的破坏形态为现三折线破坏形式。利用ANSYS完成了平面K型钢管板节点的有限元模拟分析,模拟结果与试验结果在极限承载力数值上有一定差异,但应力的发展变化规律基本是一致的。根据目前既有的节点板受压极限承载力公式对节点的极限承载力做出计算,发现节点板破坏均为失稳破坏,但计算结果与试验结果均相差较大,计算值分别是实验值的63%,68%,51%。本文根据轴心受压矩形板的弹性屈曲理论,利用我国钢结构设计规范(GB50017-2003)中的计算模型,提出等效长细比的概念,并使用等效长细比查取稳定系数来计算节点板的受压极限承载力,计算结果与试验结果比较接近,为试验值的88%。更多还原

【Abstract】 In recent years, steel tubular structures have been developing rapidly. Steel tube-gusset K joints are usually used in steel tubular structures. The previous studies mainly focused on the failure mode in which joints failed in the corner of the intersection of main tube and gusset, while gusset failure modes have seldom been studied. In the dissertation, a typical joint in a super large diameter sinking derrick was studied in order to get an in-depth investigation of the mechanical behavior, failure modes and the ultimate compressive strength of gusset-plate K joints. The joint was simplied under some assumptions. The main works in the dissertation are as follows:Firstly, a typical joint was designed and the material test offered the relevant parameters. for test and numerical simulation. Based on the test, the law of stress distribution and stress development in the joint was studied:The plastic zone was initially emerged in the two corners of the end of compressive web. Subsequently, the plastic zone spreaded to the end of the compressive web and then to both sides of the compressive web. Ultimately, three plastic zones were formed and these three plastic zones connected as an unity before the joint failed. There were three obvious broken line in the failed joint.The simulation of gusset-plate K joint was completed by using the finite element program of ANSYS. There were some differences between simulation and test in the value of ultimate strength, but the laws of stress distribution in two situations are basically consistent.According to the existing calculation models, the failures of the testing joint are all stability failure. The ultimate strengths derived from these models were different from the experimental result obviously. The calculated results were 63%,68% and 51% of experimental result respectively. Based on the elastic buckling theory of rectangle plate under axial compression and the code for design of steel structures (GB50017-2003), the dissertation proposed a new way for estimating the ultimate compressive strength. In the new method, a concept of equivalent slenderness ratio was proposed and it was employed when checking the stability factor to calculate the.ultimate compressive strength. The ultimate strength from the new method was 88% of experimental result.更多还原