设计参数对钢管混凝土系杆拱桥力学性能的影响分析

以中承式钢管混凝土系杆拱桥为计算实例,采用通用软件ANSYS建立了拱桥的有限元计算模型,通过改变其主要设计参数,对该类桥梁在恒载作用下的受力情况进行了对比分析,得出了不同矢跨比、拱轴系数、主拱拱肋含钢率等设计参数对拱桥各控制截面内力、应力、位移变化的影响规律.研究结果表明:改变矢跨比和拱轴系数对系杆拱桥在恒载作用下的内力有较大的影响,且对恒载作用下全截面弯矩的影响比对轴力的影响更为显著;改变钢管的壁厚对于主拱肋各控制截面的轴力、弯矩及应力影响不大.该计算结果可为优化同类桥型的设计提供参考.

Analysis of influence of design parameters on mechanical characteristics of concrete-filled steel tubular tied arch bridges

A finite element computing model of a CFST tied riged arch bridge is built by general finite element software ANSYS to analyze the mechanical characteristics under dead loads by changing its design parameters.The results is obtained and compared;it is shown that the different design parameters such as rise-span ratio,arch axis coefficient and steel ratio of the arc ribs have different influence on internal force,stress and displacement of any control cross-sections of CFST tied riged arch bridges.It is indicated that the changing rise-span ratio and coefficient of arch axis of the bridge affects its internal forces under dead loads evidently;it has more influence on bending moment than on axial force.It has less influence on bending moment,axial force and stress of bridge's control cross-sections by changing thickness of steel tubes.The results and conclusions can provide referrences for optimization design of this kind of bridges.