【作者】 李宇；

【导师】 雷宏刚；

【作者基本信息】 太原理工大学 ， 结构工程， 2003， 硕士

【摘要】 螺栓球节点网架的疲劳关键是高强螺栓的疲劳。目前国内外对其疲劳性能的研究大多借助疲劳试验以建立其验算方法，而对疲劳破坏机理及疲劳寿命估算研究甚少。本文以螺栓球节点网架中最常用的40Cr高强螺栓为研究对象，借助扫描电子显微镜等先进仪器对40个常幅及变幅疲劳试件断口进行了宏观及微观形貌分析，基本摸清了其疲劳破坏的机理。另外，本文在大量试验数据的基础上，依据Miner法则、相对Minar法则以及断裂力学理论，对40Cr高强螺栓的疲劳寿命估算进行了系统研究，理论分析结果与试验值的规律性吻合较好。 本文的研究成果填补了螺栓球节点网架疲劳性能在理论研究方面的空白，完善了疲劳研究方法，为《网架结构设计与施工规程》中疲劳设计方法的建立提供了重要依据。更多还原

【Abstract】 The fatigue of grid structure with holt-sphere joints is mainly the fatigue of high-strength holt. The design method of fatigue is usually established by way of fatigue tests home and abroad. A few of studies on its fatigue mechanism and life estimation are proceeded presently.In this paper, a lot of macro and micro fracture sections under equal and variable amplitude loads are analyzed on 40Cr high-strength bolts by use of scan-electronic microscope. Its fatigue mechanism is known fundamentally. Moreover, base on lots of test data, fatigue life estimation is finished by help of Miner, opposite Miner rule and fracture mechanics theory. Theoretic results and test data are well fit to each other.The research results in this paper fill the blank of the theoretic studies on fatigue behavior of grid structure with bolt-sphere joints and the fatigue research method is perfected. I believe that conclusions and suggestions will become important references for the modification of <Specification for design and construction of gridstructure> .更多还原