超高墩大跨连续刚构整幅双主墩计算长度系数的取值研究

Study on Value of Effective Length Coefficient of Full-wide Double Main Piers of Super-high Pier Long-span Continuous Rigid Frame

计算长度是受压构件承载力计算的一个重要参数。但对于规范采用的简化设计方法,构件是单独进行分析的,脱离了原来整体结构环境的约束,不能满足桥墩计算的实际需要。瓦厂特大桥主桥采用整幅双主墩,通过设置横撑将左、右幅连成一体,整体刚度较大,通过建立空间有限元压杆模型得出构件临界荷载,由欧拉公式反推桥墩计算长度系数,从而得到更接近工程实际情况的数值,对同类桥梁具有一定的指导意义。

The effective length is an important parameter for calculating the bearing capacity of compressed components. However, for the simplified design method to specifications, the component is analyzed separately, which is divorced from the constraints of the original overall structural environment and cannot meet the actual needs of pier calculation. The full-width double main piers are adopted for Wachang Bridge. The left and right spans are connected by setting the cross braces, and the overall stiffness is large. The critical load of the component is obtained by establishing the spatial finite element compression bar model, and the effective length coefficient of the pier is deduced from the Euler formula so as to obtain a numerical value closer to the actual situation of the project, which has certain guiding significance for similar bridges.