斜拉桥施工索力计算及施工偏差分析

Calculation of cable-stayed bridge construction cable force and analysis of construction deviation

以某大跨径宽桥面预应力混凝土斜拉桥为分析对象,从桥梁施工工序着手,以合理成桥状态下的弯矩和索力值为控制参数,采用正装迭代法求解桥梁斜拉索的张拉索力,并将拉索索力值、控制截面弯矩值、桥面线形与设计成桥状态进行了对比分析,闭合程度高,成桥效果良好,满足了施工和设计要求。重点分析了主梁自重、索力、弹性模量和温度四个参数的偏差对结构状态的影响。研究表明,主梁自重、索力和温度偏差对成桥状态影响较大,而混凝土弹性模量偏差则影响较小。

Taking a large-span, wide-deck prestressed concrete cable-stayed bridge as the analysis subject,starting from the bridge construction process, using the bending moment and cable force values under areasonable final bridge state as control parameters, the direct installation iterative method is employed to solvethe tensioning cable forces of the bridge’s cable stays. The cable force values, bending moment values at controlsections, deck profile, and design final bridge state were compared and analyzed, showing a high degree ofclosure with good final bridge results that met both construction and design requirements. The impact ofdeviations in four parameters, main girder self-weight, cable force, modulus of elasticity, and temperature-on thestructural state was analyzed in detail. The study shows that deviations in main girder self-weight, cable force,and temperature have a significant effect on the final bridge state, while the deviation in the elastic modulus ofconcrete has a relatively smaller impact.