薄壁高墩刚构桥稳定性研究简

修建薄壁高墩大跨度桥梁，确保桥墩的稳定性是首要考虑的问题。此文以黔江高速公路某高墩特大桥为例，根据设计的该桥结构和尺寸，基于稳定性理论，建立计算模型利用MIDAS空间计算软件计算5种模态下的安全屈曲系数，据此分析所选用桥墩材料和桥墩高度变化与桥墩稳定性的关系。通过计算与分析，随着所采用混凝土强度等级的提高，结构安全屈曲系数在逐渐增加，且桥墩的稳定性与墩高成反比。为进一步增强桥梁的稳定性，可在顺桥向增加横向支撑。

Study of Thin - wall high - pier Rigid Framework Bridge Stability

It is the primary consideration to ensure the stability of the bridge pier for the construction of thin - wall high - pier rigid framework bridges. Taking a high - pier bridge of Qianjiang highway for example, ac- cording to the constructure and size and based on the stability theory, the safety buckling coefficient un- der five kinds of mode are calculated by setting up calculation model and MIDAS space calculation soft- ware, based on which, the relationship between the selected materials and height change and stability of bridge piers are analyzed. Through calculation and analysis, it shows that with the increase of concrete strength grade, the structure safety buckling coefficient increase gradually, and the stability of the bridge piers and the pier top appear inverse ratio. In order to further enhance the stability of the bridge, the horizontal support can be increased along the direction of the bridge.