高速铁路桥梁桥基边坡稳定性及稳定坡角研究——以西成高铁养家河大桥为例

Study on Stability and Stable Slope Angle of Bridge on high speed railway——Take Yangjia River Bridge on Xi'an-Chengdu High Speed Railway as an Example

确定高陡岩质边坡的稳定坡角涉及桥梁墩台安全,是一项复杂的岩体工程问题。现有规范和研究在涉及到桥基荷载作用下岩体边坡稳定性分析及稳定坡角确定方面存在缺憾。以西成高铁养家河大桥成都侧桥基边坡为例,采用FLAC3D数值分析方法,对其不同工况下的稳定性进行分析,计算出边坡的稳定坡角。在此基础上,结合现场岩体情况,综合确定桥基边坡的稳定坡角,并得到工程的验证。研究结果表明,对于强度控制型高陡岩质边坡,首先通过数值计算确定稳定坡角,其次分析现场实测自然边坡高度、坡度、岩体产状、节理发育程度等因素,最后综合确定桥基边坡的稳定坡角。工程验证表明,该方法确定的稳定坡角既安全可靠,又经济合理,是一种有益的尝试。

It is a complex rock mass engineering issue to determine the stable slope angle of high steep rock slope, which involves the safety of bridge abutment. The existing norms and researches are deficient in the analysis of rock slope stability and in the determination of stability slope angle under the influence of bridge tbundation load. In this paper, a FLAC3D numerical analysis method is used to analyze the stability of Chengdu-side slope of Yangjia River bridge on Xi＇an-Chengdu high speed railway and to calculate the stability of the slope. On this basis, the stable slope angle of the bridge slope is determined according to the site rock mass, and the engineering is verified. The results show that the stable slope angle of the high steep rock slope with strength control is determined by numerical calculation, and the factors of natural slope height, slope, rock mass yieht and joint development are analyzed. The engineering verification demonstrates that the stable slope angle determined by this method is sat~, reliable, economical and reasonable.