刚构悬索组合体系桥梁抗震性能研究

刚构悬索组合体系桥梁可以改善常规大跨径连续刚构桥跨中持续下挠问题。文章选择一座跨径组合的刚构悬索组合桥梁为研究对象, 采用 OpenSees 软件建立其弹塑性三维动力有限元模型, 对其进行非线性时程分析和易损性分析。结果表明, 刚构悬索组合体系的动力特性与刚构桥类似。矢跨比会对横桥向地震作用下的塔顶位移、塔底弯矩和墩顶弯矩产生影响。易损性分析结果显示, 桥塔在地震作用下基本保持弹性。

Rigid-frame suspension composite bridges can relieve the problem of continuous mid-span deflection of traditional long-span continuous rigid-frame bridges. In this paper, a rigid-frame suspension composite bridge with span combination was selected as the case study. The elastoplastic three-dimensional dynamic finite element model of the bridge was built by OpenSees software. Nonlinear time history analysis and fragility analysis were carried out. The results show that the dynamic characteristics of the rigid-frame suspension bridge are similar to those of rigid-frame bridge. The rise-span ratio affects the displacement at the top of tower, the bending moments at the bottom of tower and at the top of pier under transverse earthquake. The results of fragility analysis show that the bridge tower remains elastic under earthquakes.