钢-UHPC轻型组合梁桥面板结构型式研究

摘要

To address the issue of cracking in traditional steel-concrete composite bridge,the steel-UHPC lightweight composite bridge structure was proposed.① Light-weight steel-UHPC composite beam was compared with the traditional steel-concrete composite beam conventional steel-concrete composite bridge from aspects of economy and mechanical properties,it''s a new promising structures has lighter self-weight,superior mechanical performance and convenient construction,as well as satisfactory lift-cycle economic performance.② Three kinds of deck slabs including rectangular slab,thinner rectangular slab with longitudinal ribs and Waffle deck panel was analysied by means of finite element analysis.Results indicate that the Waffle deck panel has largest stiffness,resulting in the lowest deflection.For the deck panel with longitudinal (and transverse) ribs,the severest longitudinal tensile stresses located in the bottom of longitudinal ribs so that the longitudinal tensile rebar can be only collocated in the bottom of longitudinal ribs.Based on the scheme of Waffle deck panel,full-scale strip model was designed and tested.The experiment shown that the first crack stresses subjected to positive and negative moment are 19.4 MPa and 9.4 MPa,respectively.And the crack stress can meet the crack width limit of the serviceability limit state.%提出了钢-UHPC轻型组合桥梁结构,以克服传统钢-混凝土组合结构桥梁混凝土桥面板的不足.① 从基本力学性能和经济性方面对轻型组合梁和传统组合梁进行对比,表明轻型组合梁具有自重低,力学性能优越,施工方便快捷,全寿命经济效益显著等特征,具有较好的应用前景.② 对等厚板、带纵肋桥面板、华夫桥面板3种结构型式的UHPC桥面板进行有限元分析,结果表明:华夫桥面板竖向位移最小,整体刚度最大;带纵(横)肋桥面板仅纵肋下缘纵向拉应力最大,只需在纵肋下缘配置纵向受拉钢筋;华夫桥面板方案横向拉应力峰值小于较带纵肋方案.③ 基于华夫桥面板方案开展了足尺条带模型试验,正负弯矩试验的初裂应力分别为19.4 MPa和9.1 MPa,华夫桥面板方案能够满足正常使用极限状态的裂缝限值.