太中银铁路地震液化带桥梁深基坑开挖施工技术

对太巾银铁路地震液化带桥梁深基坑开挖的施工技术进行了研究.首先依据太中铁路地震液化带地区的地质特点,详细地分析了地震液化带软上地区桥梁深基坑开挖过程中存在的施T技术问题;提出了真空轻型井点降水、钢管桩围堰和两者相结合的方案来解决太中银铁路地震液化带桥梁深基坑开挖施工过程中可能出现的喷砂冒水和滑坡等灾害.通过分析和试验结果的研究表明,在地震液化带区域采用井点降水和钢管桩围堰及其相结合的方法进行深基坑开挖支护是可行和有效的.

Excavation Technology of Deep Foundation Pits for Railway Bridge on Taiyuan-Zhongwei-Yinchuan Railway in Earthquake Liquefaction Belt

The technology for excavation of deep foundation pits for a railway bridge on the Taiyuan-Zhongwei-Yinchuan Railway in earthquake induced liquefaction belt is studied.In the paper,the technical problems in excavation of deep foundation pits for the railway bridge in the soft soil in the earthquake induced liquefaction belt are analyzed in detail on the basis of the geological conditions of the earthquake induced liquefaction belt on the Taiyuan-Zhongwei-Yinchuan Railway.Vacuum light-duty well points for dewatering,construction of steel tubular pile cofferdams and an alternative combining both methods are proposed to overcome the problems of sand and water emission and landslides which may develop during the excavation of deep foundation pits for the railway bridge on the Taiyuan-Zhongwei-Yinchuan Railway in earthquake induced liquefaction belt.The results of tests and analysis show that it is feasible and effective to employ the method of dewatering by well points and construction of steel tubular pile cofferdams as well as the alternative combining both methods to excavate and brace up the deep foundations in earthquake induced liquefaction belts.