【作者】 刘建涛；

【导师】 司秀勇； 刘春凤；

【作者基本信息】 燕山大学 ， 建筑与土木工程（专业学位）， 2018， 硕士

【摘要】 索作为一种高效的柔性受拉构件,在桥梁、弦支穹顶、张拉整体等结构中发挥着重要作用,而在索的计算理论中,关于连续曲线索的滑移问题是无法避免的。连续曲线索被广泛地应用于输电线路架设找形、缆索桥梁施工以及运输索道等领域。参考和总结国内外关于连续曲线索滑移问题的研究,本文提出一种能在ANSYS通用有限元软件中实现的连续曲线索滑移算法,并用来指导工程实践。基于抛物线和悬链线两种曲线索理论,用数学方法推导了索力、索长和垂度的解析解。基于有限元基本原理,从普通索单元出发,对空间两节点索单元进行了理论分析。采用虚功原理推导连续折线索单元刚度矩阵和质量矩阵的表达式。利用FORTRAN语言编制折线索的有限元计算程序,并通过UPFS二次开发功能将该单元写入ANSYS单元库。本文联合使用两节点直线索单元和三节点连续折线索单元,通过找形计算模拟连续索的曲线线形,并在支座处加入折线索单元使索力满足连续条件。通过滑移方向和滑移量判断,实现折线索单元的重布置,编制算法流程图。通过算例验证了本文方法的可行性,将计算结果与解析解和其他文献对比表明,该方法计算精度高,适用范围广泛,不受跨度和垂度的限制。同时,在解决滑移问题时不需要复杂的迭代程序,计算速度快,且本文编写的折线索单元可与有限元软件中其它梁杆单元连接并协同工作。更多还原

【Abstract】 As a kind of efficient flexible tension member,the cable plays an important role in the structure of bridge,suspend dome and temerity.However,in the calculation theory of cable,the slid problem of continuous curve cables is unavoidable.It’s widely used in transmission lines erection,cable bridge construction,and transportation cableways.In this paper,a continuous curve cables sliding algorithm was proposed which can be implemented in general finite element software by reference and summary of research on continuous curve cable’s sliding at home and abroad,and used to guide engineering practice.Based on two kinds of curve cable theory of parabola and catenary,derive the analytic solution of cable’s force,length and sag by mathematical method.Starting from the common cable element,theoretical analysis is carried out on two-node line element based on the basic principle of finite element.Use virtual work principle to derive the expression of stiffness matrix and mass matrix of the continuous linear cable element.A finite element calculation program for linear cables was redacted using FORTRAN language,and write this element to ANSYS through the second development function of UPFS.In this paper,combination two-node cable element with three-node continuous linear cable element,simulate the curve line of continuous cables by shape finding calculation,and adding a linear cable at the support to satisfy the continuous condition.Layouts the three-node continuous linear cable element through slid direction and slid volume,and compile the algorithm flow chart.Then,test the feasibility of this method by examples.The comparison of the results with some analytical values and other literatures indicates that this present method has high accuracy,wide range of application,and is not limited by span and sag.At the same time,in solving the slid problem,no complicated iterative procedure is required,and the calculation speed is fast.In addition,the new element can be connected with other beam or cable elements in finite element software.更多还原