中文摘要：

根据几何、物理以及边界条件相似原则,设计绵阳城南新区1号桥桥塔钢—混凝土结合段的缩尺试验模型。对试验模型分别进行正常使用极限状态与承载能力极限状态加载,测试试验模型控制断面和主要构件的应力、变形随加载历程的变化。试验结果表明：结合段钢结构、混凝土结构及PBL键贯穿钢筋的应力水平较低,钢箱与混凝土之间相对滑移量较小,钢箱与混凝土之间共同受力工作性能良好,钢结构的荷载被比较顺畅地传递到混凝土结构上,这说明该桥结合段的设计合理,满足安全性要求,且具有较高的安全储备。

英文摘要：

Based on the similarity principle of geometry,physics and boundary conditions,a reduced scale test model of the steel-concrete joint section of the No.1 bridge tower in the new south district in Mianyang was designed.The test model was loaded according to the serviceability limit state and ultimate limit state separately,and the variations of stress and deformation of the control sections and main members with loading history were obtained.As shown in the results,the stress of the steel structure,the concrete structure and the steel reinforcement of PBL shear connector in the joint section is lower.The relative slip between steel box and concrete is smaller.The steel box and concrete work together well,and the load from the steel structure is smoothly delivered to the concrete structure.It indicates that the joint section of the bridge is reasonably designed.It has enough emergency capacity and meets safety requirements.