新型装配式拱圈节段的转动刚度分析与设计研究

Rotational Rigidity Analysis and Design Study of Arch Ring Segment for New Type Prefabricated Arch Bridge

牛路河特大桥为应用缆索吊装技术施工的拱桥,拱圈节段间采用企口加胶接与临时精轧螺纹钢组合的新型连接形式,但如何确定其平面内转动刚度还没有可参考的计算方法。以此桥为研究对象,为了便于工程应用将混凝土刚体化,且忽略混凝土接触面之间胶的作用,探究了新型连接形式下节段间转动刚度的计算方法,然后与精细化有限元模拟的结果进行了对比,吻合较好;最后建立了计算转动刚度与刚接下的拱圈Midas施工阶段模型,对比计算结果发现相对于拱圈节段间刚接,计算转动刚度下拱圈在施工阶段的最大拉应力和最大压应力都有所减小,且与实际监控数据更吻合。

The Niulu River Bridge is a prefabricated arch bridge which is constructed by cable hoisting,and the connection between arch ring segments applies a new composite form consisting of tongue-and-groove,glued connection and fine-rolled rebars.For this type of connection,calculation method for determining its in-plane rotational stiffness is needed to be investigated.Thus,based on this bridge,a calculation method for the rotational stiffness between segments of this new connection form was carried out,in which the concrete was assumed as rigid to facilitate engineering application and the glue effect between the concrete contact surfaces was ignored.By comparing the results between this calculation method and refined finite element simulation,it showed good agreement.Finally,different Midas construction models of the arch ring using proposed rotational stiffness and rigid joint were established,respectively.Compared with the calculation results of the rigid connected arch rings,the maximum tensile stress and the maximum compressive stress of the arch ring using proposed rotational stiffness in the construction stage were smaller,which were more consistent with the actual monitoring data.