城市高架简支预制槽形钢混组合梁荷载横向分布研究

摘要:

本文以城市高架简支预制槽形钢混组合梁桥为研究对象，选取了桥面板与钢梁之间的滑移效应、跨间横梁的个数、桥面板板厚、桥梁宽度和跨径、以及主梁刚度等参数，应用有限元方法，全面分析了各因素对该桥型荷载最不利横向分布系数的影响。研究表明：组合梁的界面滑移效应对荷载最不利横向分布系数影响在5%以内；保证跨径一定，组合梁跨间横梁的个数对宽桥荷载最不利横向分布系数的影响在8%以内，对窄桥则更小；桥面板板厚的增加会使荷载横向分布更均匀，宽跨比越大的桥，板厚对最不利横向分布系数的影响越大；保证桥宽不变，随着跨径的增大，荷载最不利横向分布系数逐渐减小，主梁数相同时，随着宽跨比的增大，最不利横向分布系数逐渐增大。梁高的增加会使最不利横向分布系数更大，但最大增幅保持在5%以内。在今后的标准化设计中，可取某几种最不利参数将其余参数进行包络，从而节约设计成本、提高设计效率。

Abstract:

This paper takes urban elevated steel-concrete composite beams as the research object, the parameters such as sliding effect between deck and steel beam, the number of diaphragm beam, the thickness of deck, the width and span of bridges and the stiffness of main beams are selected, and the influence of various factors on the most unfavorable lateral distribution coefficient under vehicle load of this bridge type is comprehensively analyzed by using the finite element method. The research shows that the interface slip effect of composite beams is within 5% on the most unfavorable lateral distribution coefficient. Under the premise of ensuring the same span, the influence of the number of beams in the composite beam on the most unfavorable lateral distribution coefficient is within 8% and it is even smaller for narrow bridges. The increase in the thickness of the bridge deck will cause the load to be transverse distribution more uniform, and the greater the width-span ratio, the greater the influence of the plate thickness on the most unfavorable lateral distribution coefficient. As the span increases, the most unfavorable lateral distribution coefficient gradually decreases, when the number of main beams is the same, as the width-span ratio increases, the most unfavorable lateral distribution coefficient gradually increases. As the girder height increases, the most unfavorable lateral distribution coefficient gradually increases，but the increase of the t most unfavorable lateral distribution coefficient is within 5%. In the future standardized design, some of the most unfavorable parameters can be used to envelop the remaining parameters, thereby saving design costs and improving design efficiency.