Circular arch is rational for big rise - span ratio , but each has his strong point for small rise - span ratio . ( 3 ) the common used rise - span ratios are 1 / 6 - 1 / 12 . by the decrease of rise - span ratio , the internal forces are increasing linearly except of the moment of open spandrel beam ( 3 )空腹式刚架拱桥的矢跨比一般为1 6 1 12 ，随着矢跨比的减小，除了空腹段加劲梁的弯矩值线性减小外，其余截面的内力值均为线性增大。
On the basis of the basic theories and methods about stability analyses , arc - length method is used to analyze the geometrical nonlinear stability of the structure . and the effects of the rise - to - span ratio and the prestress in cables etc . on the structural stability are discussed 本文在介绍了结构稳定分析理论和方法的基础上，采用弧长法解算了环状索杆结构的几何非线性稳定性问题，并研究了矢跨比、预应力等结构参数对其稳定性的影响。
Compared with the relevant single - layer reticulated dome , the dynamic characteristics is studied and the effects of the rise - to - span ratio and the prestress in cables etc . on the dynamic characteristics are discussed in this thesis . some proposals can be applied to practical engineering 文中研究了环状索杆结构的动力特性，分析了矢跨比、预应力、约束方式等结构参数对结构自振特性的影响，并与相应的单层网壳结构作了对比，得出一些有益于结构设计的结论。
Finally a fact double - layer reticulated spherical shell is analyzed . the change of parameters , such as ratio of height - span , shell ' s thickness , stochastic flaw and disposal of load so on is considered , and more than 200 results on ultimate load - carrying capacity are obtained 利用本文程序对一个双层球面网壳结构的工程实例进行了分析:考虑网壳结构设计中的主要参数如矢跨比、网壳厚度、初始缺陷以及荷载分布等变化,计算结构的极限承载力,共得到200多个结果。
This paper introduced the composition and classification of suspendome , generalized the nonlinear finite element computing methods . analysis to suspend - dome and single layer reticulate is conducted separately to the five type suspendomes which have same span but different rise - span , including force , displacement , eigenvalue buckling , nonlinear buckling , load - displacemnt tracking and nonlinear ultimate carrying capacity , every performance of suspendome was expatiated in the paper 通过对同一跨度、不同矢跨比的5种弦支穹顶结构和单层网壳进行的静内力、节点位移、结构体系应变能、特征值屈曲、非线性屈曲、非线性极限承载力、荷载-位移平衡路径跟踪分析和比较,阐述了弦支穹顶结构的各项性能,通过与单层网壳的比较,阐明了弦支穹顶结构的优越性。
The software ansys6 . 0 is used to analysis the stability of the state after construction of tongwamen bridge , linear method is used in analyzing the finite element model of the bridge , the coeffient of stability of different state after construction is given . on the basis , the effect of different factors such as the arrangement of lateral brace , the sloping angle of arch ribs , the stiffness of bridge deck system , the effect of non - orientedly conservative loadings of the hanger and tie bar etc is discussed . the different coefficients of stability of changing these factors are given , so the factors that are vital to the lateral stability of x - type arches are found , and the rationality of the methods taken to enhance the lateral stability of tongwamen bridge is evaluated 本文应用有限元分析商业软件ansys6 . 0 ，采用线弹性方法，通过对该桥的空间有限元模型进行稳定性分析，得出其成桥运营阶段各种工况下的稳定安全系数。在此基础上，本文还通过有限元模型分析，就拱的矢跨比、吊杆(立柱)的非保向力效应、桥面系的刚度、横撑布置形式、拱肋侧倾角等因素对该桥整体稳定性的影响展开探讨与研究。文中给出了各因素变化情况下的稳定安全系数，指出了对钢管混凝土提篮拱横向稳定性有显著影响的因素及其合理变化范围，并对铜瓦门大桥提高横向稳定性的措施的经济合理性进行了分析。
The effects of the cable arrangement on the structural performances are discussed in this thesis . the effects of the rise - to - span ratio and the prestress in cables with different cable arrangement are studied and the optimized cable arrangements are found . finally , some conclusions are summarized and the topics for further research are put forward 本文研究了布索对大型环状索杆结构力学性能的影响，同时分析矢跨比、预应力等结构参数变化时不同布索工况下结构的力学性能的变化，得出各类索对结构力学性能的影响，并由此得到几种优化的布索组合。
In addition , the analysis and test for the entire stability and limited carrying capacity are completed and results show that pingsheng bridge is also safe enough . 4 . the influence on the static performance for pingsheng bridge of structural parameters , such as rise - span ratio of main cable , stiffened girder rigidity , main tower rigidity and main cable rigidity , is studied 对平胜大桥和与之具有相同结构参数的地锚式悬索桥模型进行了动力特性分析,并研究了主缆矢跨比、恒载集度、加劲梁刚度、主塔刚度、主缆抗拉刚度、吊索抗拉刚度等结构参数变化对两类悬索桥动力特性的影响。
Dynamic characteristic of orthogonal vierendeel dome was discussed , and the influence on vibration characteristic acted by difference including rise - to - span ratio , shell thickness , section area and constraint condition was studied . vibration shapes - separation - spectra - method and time - history method were adopted to analyze the dynamic response of orthogonal vierendeel dome under common earthquake . by comparing dynamic response in different direction and dimension seismic excitation , the value and distribution of dynamic internal force were obtained 本文研究了正交空腹网壳结构的动力特性，分析了矢跨比、网壳厚度、腹杆截面和支座约束条件对结构自振特性的影响；采用反应谱法和时间历程法对正交空腹网壳的地震响应作了详细的分析，分别研究了结构在不同方向地震激励下和在不同维数地震激励下动力响应的数值大小和分布规律，并比较了两种方法的结果差异，对抗震设计具有参考价值。
That the arched roadway with the ratio of 0 . 2 between arch rise and roadway width is substituted fur rectangular roadway can obviously improve the stress state of roadway surrounding rocks , reduce the deformation and the plastic yield area of roadway surrounding rocks , greatly strengthening the stability of roadway surrounding rocks 采用矢跨比为0 . 2的圆弧拱巷道代替矩形巷道，可显著改善巷道围岩应力状况，减小巷道围岩变形量，减少围岩塑性屈服区域，加强巷道围岩的稳定性。
