Abstract : in this paper the complex load distribution acted by running flood on a typical spandrel - filled arch bridge has been analyzed and calculated , and through a simplified mechanical arch model the corresponding innersetion forces are evaluated to render the safety check on the arch spaicial resistance 文摘:从山洪形成破坏力的特征入手,遵循桥梁结构所必备的维持平衡稳定的自身抗力,去抵御山洪破坏力的准则,导出了拱桥抗御山洪的设计验算与预测模型,以期在实践中提供安全设计或维护对策的借鉴
It shows that the result of resistance under bending and torsion by this method is almost same as that of experiments . correlate equations of bearing capacity of this structure under complex loads are deduced . four expressions of bearing capacity of this structure under complex loads , which are press , bending and torsion , are deduced in the end 最后利用轴压、弯曲和扭转作用的两两组合作用下的极限承载力相关方程,通过适当的简化处理,就得到偏于安全的离心钢管混凝土构件在轴压、弯曲和扭转三种荷载共同作用下的承载力计算公式。
First , the theory of fretting wear and studies on fretting fatigue were introduced and the parametric method was used in the process of creating the model of dovetail joints in ug software . the elastic contact problem is analyzed in finite element method ( fem ) and is used to the parameters " distribution and contact stress of the joint are obtained on the base of ansys code . with the effect factor of load frequency , the prediction method of fretting fatigue life of dovetail joint under low and high / low cycle complex load is proposed 本文介绍了微动损伤的机理和微动疲劳寿命的研究方法;利用ug软件对燕尾榫联接结构创建了参数化实体模型;基于ansys软件平台求解弹性接触问题,获得了榫联接结构接触应力及接触状态量的分布;在已有微动疲劳寿命预测模型的基础上,引入载荷频率影响因子,对低周、高低周复合载荷作用下的燕尾榫联接结构进行了微动疲劳寿命的预测,与试验结果对比表明采用本文提出的方法预测榫联接结构的微动疲劳寿命是有效的。
Under the complex loadings , the surface flaws of large complex structures and the original defects of materials would initiate the propagation of micro three - dimensional ( 3d ) cracks , and result in catastrophic accidents . for the limitations of the traditional theories of two - dimensional cracks , the safety of actual structures containing 3d cracks cannot be guaranteed completely without the out - of - plane stress constraint 复杂应力作用下,宏观复杂结构表面加工质量和材料本身固有缺陷以及外来损伤等会引起三维裂纹的萌生、扩展,最终导致灾难性的破坏,而传统二维裂纹理论在解决实际三维裂纹问题时出现不足,无法完全保障结构安全。
Ordinary bolt connecting bolts as a permanent use , when the design requirements or questions about its quality should be carried out when the smallest lag bolts kind complex load testing and the results were consistent with national standard 《 mechanical fasteners , bolts , screws and stud 》 ( gb3098 ) 普通螺栓作为永久性连接螺栓使用时,当设计有要求或对其质量有疑义时,应进行螺栓实物最小拉力载荷复验,其结果符合国家标准《坚固件机械性能、螺栓、螺钉和螺柱》 ( gb3098 )的规定。
In the design , the construction measures such as application of shrinkage - compensating concrete , arrangement of spacing layer between the foundation rock and the bottom slab , adding outside waterproof layer , flexible connection between outlet pipe with side - wall , integerated concrete placement of pump seat with bottom slab and design of reinforcement with application of advanced calculation theory are used according to the characteristics of lager span , larger volume and complex loading conditions of the understructure 针对下部结构跨度大、体积大、受力复杂的特点,在设计中采取多种措施,包括采用补偿收缩混凝土、基岩与底板间设隔离层、增设外防水层、出水管与边墙采用柔性连接、机座与底板整体浇注、采用先进计算理论指导配筋。