上承式现代竹拱桥的力学性能数值分析

Numerical analysis on mechanical performance of bamboo plywood bridge

基于ANSYS平台对上承式现代竹拱桥的力学性能进行了数值分析,计算出竹拱桥结构的强度(应力)、刚度(变形)值以及自振频率。为优化结构,建立了10个不同矢跨比拱桥模型,分别对它们的拱圈弯矩、轴力、挠度和拱脚处反力值以及自振频率等进行比较,从而获取合理矢跨比。结果表明:该结构拱圈应力远小于竹胶板抗压强度值,而其刚度要求成为设计控制指标。随矢跨比变化,拱圈弯矩、挠度与竖向频率呈抛物线形变化;拱圈轴力、侧向频率及拱脚处反力呈折线段变化。该拱桥合理矢跨比为1/3.6。

The type of modern bamboo arch mechanical performance was studied by numerical analysis based on the ANSYS platform,and the structure strength（ stress） and stiffness（ deformation） value were obtained. In order to optimize the structure,ten different rise span ratio of arch bridge model were built and calculated. Comparing the value of arch moment,axial force,deflection,natural frequency and force of supports,the reasonable rise-span ratio was gotten. The results show that the structure of arch stress is far less than the allowed value,and the stiffness requirement becomes the control index of design. The relationship curves of moment-rise-span ratio,vertical frequency-rise-span ratio and deflection-rise-span ratio are the parabola. The curves of arch axial force-rise-span ratio,lateral frequency-rise-span ratio and force bearing-rise-span ratio are broken line. The structure reasonable span is almost 1 /3. 6.