矮塔钢-混凝土组合梁斜拉桥的索力优化

文章根据矮塔斜拉桥的结构形式和受力特点,采用钢-混凝土组合梁为主梁,充分发挥钢-混凝土组合梁钢筋受拉、混凝土抗压的性能优点,进一步研究矮塔钢-混凝土组合梁斜拉桥的索力优化。针对该类桥型确定成桥状态和索力优化的方法,以弯曲能量为目标函数1]、基于最小二乘法原理和影响矩阵法,确定最优索力(即施工时的合理张拉索力)。利用有限元程序MIDAS/CIVIL2017对以钢-混凝土组合梁为主梁的矮塔斜拉桥进行索力优化,并对优化前后主梁的挠度、内力以及应力结果进行对比分析。通过MIDAS/CIVIL2017对索力的优化,可以更好的发挥出钢-混凝土组合梁较强的承受竖向荷载能力的特点,改善主梁的内力、弯矩、应力分布。

Optimization of Cable Force of Low-Pylon Cable-Stayed Bridge with Steel-Concrete Composite Girder

According to the structural form and mechanical characteristics of the low-pylon cable-stayed bridge, the steel-concrete composite beam is adopted as the main beam in this paper to give full play to the advantages of steel-concrete composite beams in tension and compression. This paper studies the cable force optimization of the low-pylon steel-concrete composite beam cablestayed bridge. For this type of bridge, the optimal cable force(i.e. the reasonable tension force during construction) is determined based on the bending energy as the objective function, the least square method, and the influence matrix method. In this paper, MIDAS/civil2017 is used to optimize the cable force of the cable-stayed bridge with the steel-concrete composite beam as the main beam, and the results of deflection, internal force and stress of the main beam before and after optimization are compared and analyzed. Through MIDAS/civil2017 to optimize the cable force, the steel-concrete composite beam can better play the characteristics of strong vertical load-bearing capacity and improve the internal force, bending moment, and stress distribution of the main beam.