代换梁法在自锚式悬索桥上的推广应用

EXTENSIONAL APPLICATION OF SUBSTITUTIONAL BEAM METHOD TO SELF-ANCHORED SUSPENSION BRIDGE

为了解决自锚式悬索桥活载内力计算问题,按照我国著名学者李国豪教授提出的代换梁法的基本原理,分析了自锚式悬索桥和传统地锚式悬索桥的构造和受力的不同点,对自锚式悬索桥提出了新的计算模型,由此导出了因活载对主缆产生水平拉力分量的计算公式,从而解决了确定自锚式悬索桥加劲梁内力的问题。通过一座桥例的分析,用该方法所得到的计算结果与空间及平面有限元法的分析值基本吻合。因此,该方法对设计具有实用意义。

In order to calculate the internal force of the self-anchored suspension bridge under live loads, a new computing model is established. The new model adopts the fundamental principle of substitutional beam method provided by Chinese famous professor Li Guohao, and accounts for the differences in configuration and loading between self-anchored suspension bridge and traditional suspension bridge. A formula is derived to calculate the horizontal component of the pulling force of the cable caused by live loads; thereby, the internal forces of the girder in self-anchored suspension bridge can be determined. The proposed method is illustrated with a bridge. Comparing with results from two-dimensional and three-dimensional FEM, the accuracy of this method is demonstrated to be reasonable. Therefore, the proposed method can be used in bridge design.