【作者】 张宁；

【导师】 殷志祥；

【作者基本信息】 辽宁工程技术大学 ， 结构工程， 2008， 硕士

【摘要】 冰雪灾害和地震灾害下失稳破坏的钢结构很多,尤其是结构形式趋于轻型和薄壁的大跨度空间结构,失稳破坏往往突然发生,没有明显征兆,通常会造成大量的人员伤亡和巨大的经济损失。双向张弦梁结构作为一种新型的大跨度杂交结构体系,相对于普通结构具有很强的几何非线性,结构稳定性问题值得研究。本论文通过ANSYS软件的APDL语言建立双向张弦梁结构的参数化模型。在考虑结构初始几何缺陷的基础上进行结构的静力稳定性分析,同时考虑材料和几何的双重非线性,采用大变形非线性分析得出结构的极限荷载值,并通过荷载—位移曲线分析整个结构的失稳过程。随后分析结构的极限荷载值随矢跨比、垂跨比、支座形式和索内应力等参数的变化情况,得出保持结构稳定性的最佳参数值。进行三向地震荷载(EL-Centro波)作用下的动力稳定性分析,根据结构可能出现的两种失稳形式提出确定动力稳定性临界荷载值的判别方法:索内力判别和荷载—位移曲线判别;根据荷载形式提出一种新的判别方法——动力响应判别法,即结构节点位移随时间的变化情况判别。三种判别方法均得出相同的临界值,说明判别方法的正确性和可行性。随后分析结构的动力稳定性随矢跨比和垂跨比这两个参数的变化情况,得到双向张弦梁结构动力失稳的特点,为以后的工程设计提供参考。更多还原

【Abstract】 There are many steel structures of unstable failure in the ice and snow disaster and earthquake disaster, especially the long-span spatial structure which tends to light and thin-walled. Its destroy often suddenly occurs and it does not have the obvious indication. So it often causes the massive personnel casualty and the huge economic loss. Bidirectional beam string structure as a new type of long-span spatial steel structures whose application becomes more and more abroad is a hybrid structure system between the rigid structure and the flexible structure, whose stability is worth studying.This paper makes use of ANSYS to establish the bidirectional beam string structural parametrization model with APDL. It does the static stability analysis based on considering the initial geometric imperfection, considering the material and geometry dual nonlinears. It gets the ultimate load through the non-linear static analysis with large deformation. It analyses the course of structural instability by the load - displacement curve. Then it analyzes the change of the ultimate load along with the rise-span ratio、the rag-span ratio,support form and the internal stress of cables and gets the optimum parameter value to the stability.It carries on the dynamic stability analysis under three-dimensional earthquake load (EL-Centro wave). It proposes discrimination methods to obtains the critical load according to two kinds of instability forms: the internal force of cables discrimination and load - displacement curve discrimination. It also proposes a new type of discrimination method based on the load—dynamic response discrimination, which is discriminanted by the change of the node displacement along with time. It gets the same critical load value in three methods to proof the correctness and feasibility of discrimination methods. It obtains the change of dynamic stability of structure along with the rise-span ratio and rag-span ratio. It understands the dynamic instability characteristics of the bidirectional beam string structural, and provides the reference for later engineering design.更多还原