京沪高速铁路南京大胜关长江大桥节段模型试验研究

【作者】 胡文军；

【导师】 叶梅新；

【作者基本信息】 中南大学 ， 结构工程， 2008， 硕士

【摘要】 南京大胜关长江大桥是京沪高速铁路上一座6线铁路三主桁的六跨连续钢桁梁(拱)桥,桥式布置为(108+192+336+336+192+108)m,桥面系采用混凝土板与钢正交异性板相结合的道碴整体桥面结构,多横梁体系,该桥式结构新颖,受力复杂。本文对该桥完成了桁段和拱段两个节段模型试验研究,较为系统地考察了三主桁整体桥面结构的受力性能。完成的主要工作如下:1、设计、制作了两个六节间1:6的节段模型,一个桁段模型,模拟实桥(108+192)m钢桁梁段受力;另一个是拱段模型,模拟实桥336m钢桁拱段受力。2、提出了桥面加载辅以节点加载的“组合加载”方式,节点加载补充了节段模型的“第一系统”受力,实现了用节段模型模拟全桥受力的试验目的。3、提出了用不同的支承方式模拟实桥钢桁梁正弯矩区段和中支座负弯矩区段受力状态的试验方法。每个模型完成了7个工况的试验,考察了三主桁整体桥面结构不同区段各荷载工况下的受力性能。4、对拱段纯钢模型和钢混模型各完成了7个工况的试验,模拟了实桥拱段各种荷载作用下的受力,考察了三主桁拱整体桥面结构的受力性能。5、对拱段纯钢模型和钢混模型的试验结果进行了对比分析,研究了混凝土桥面板对桥梁刚度和受力行为的影响。结果表明:考虑了混凝土道碴板后,桥面系的整体刚度增加;系梁、纵梁和非桥面系杆件应力有所降低;节点横梁正应力有所增加。6、将模型试验结果与实桥有限元分析结果进行了对比分析,考察了有限元分析结果的正确性。结果表明:模型的应力水平与实桥的应力水平大体相当,有限元分析结果正确,用节段模型模拟全桥受力的模拟方法可行。本文的研究成果为南京大胜关长江大桥设计、施工提供了依据,对其他模型试验也有参考价值。更多还原

【Abstract】 Nanjing Dashengguan Yangtse River Bridge is a steel truss girder (arch) bridge with six spans, three-truss, six railway lines on the high-speed railway from Beijing to Shanghai. The span arrangement is (108+192+336+336+192+108) m. It takes the form of multiple transversal girder system with the orthotropic steel ballast monolithic deck. The mechanical behavior of this new type bridge is very complicated. Two model tests were performed. One is truss segment model test, the other is arch segment model test. The mechanical behaviors of three-truss monolithic deck structure were systematically investigated in this paper. The main work has been done as follows:1. Two 1:6 six-segment models were designed. One is from the span (108+192) m to simulate the mechanical behaviors of truss girder span; the other is from the span 336m to simulate the the arch span.2. "Combined loading" method that deck loading combined node loading was proposed. Node loading compensates the "first system" stress to ensure that the segment model can perform as the real bridge.3. In truss segment model, both positive moment zone and negative moment zone near support of steel truss girder span were simulated using different support modes. Seven load cases were completed to simulate the mechanical behaviors of the steel truss girder span under various loads, and to study the mechanical behaviors of three-truss monolithic deck structure.4. In arch segment model, steel model test and steel-concrete model test were performed. Seven load cases were completed to simulate the mechanical behaviors of the arch span under various loads, and to study the mechanical behaviors of three-arch monolithic deck structure.5. The results of steel model test and steel-concrete model test were researched comparatively. The influence of concrete deck on mechanical behavior of the bridge was studied. The results showed that: considering the concrete ballast slab, the integral stiffness of the floor system increases, the stress of the tie beam, the stringer and the members of non-floor system decreases, and the stress of the transversal girder in the joint increases.6. The results of segment model test and FEM for real bridge were researched comparatively. The correctness of FEM was investigated .The results showed that: the stress level between the model test and the real bridge is close, the FEM result is correct, and the simulation method that segment model simulates the real bridge is correct.The production of this paper can provide the basis for the design and the construction of Nanjing Dashengguan Yangtse River Bridge and provide references for other model test.更多还原