地锚式单跨独斜塔斜拉桥受力特点研究

Mechanical Characteristics of Earth-Anchored Cable-Stayed Bridge with Single Inclined Pylon and Single Span

芙蓉江大桥为地锚式单跨独斜塔斜拉桥,具有"斜塔"、"地锚"、"单跨"、"全混凝土"和"大跨"五大特点。为研究其受力特点和设计要点,选取地锚箱位置、主塔倾斜角、斜向高度、主塔和主梁自身刚度5种关键参数详细研究了它们对大桥受力的影响,进而得到了全桥受力较为合理的参数取值。研究表明:地锚箱距离主塔较远时,锚索对主塔整体刚度的提升效果较好,但对主梁竖向刚度影响很小;增大主塔或主梁自身刚度对提高全桥刚度和振动频率作用很小,调整地锚箱位置等关键参数作用很大。

Furongjiang River Bridge is an earth-anchored single span and single inclined pylon cable-stayed bridge, with five major characteristics, that is ＂pylon＂, ＂earth-anchored＂, ＂single span＂, ＂full concrete＂, and ＂large span＂. Five key pa-rameters, namely, the earth anchorage box position, the inclination angle and oblique height of pylon, self-stiffness of pylon and girder were selected to study their impacts on bridge stress. And then, more reasonable parameter values of the fullbridge stress state were obtained. The results show that anchor cable has more contribution on the overall stiffness of the pylon when the earth anchorage box position is far away from the pylon, but it has little impact to the vertical stiffness of girder. Increasing self-stiffness of pylon and girder has very little effect on the full-bridge stiffness and vibration frequency, while adjusting key parameters, for example, the position of earth anchorage box, is more efficient.