【摘要】 茅草街大桥是洞庭湖区上的一座特大型桥梁,地处湖区淤泥质软土地层。淤泥质软土地基力学性质差,承载力较低,施工难度大。根据施工现场条件做好施工准备工作,制定施工方案。大孔径钻孔灌注桩钻孔时,采用钻机反循环低档钻进的方法,成孔后开始导管反循环清孔。钻孔灌注桩水下混凝土采用提升导管法施工,水上混凝土灌注采用拔球的施工技术,介绍了施工注意事项及应对措施。施工完毕后,经检查54根钻孔灌注桩全部合格,满足设计和相关规范要求。更多还原

【Abstract】 As an oversize bridge,Maocaojie bridge is located in mucky soft soil layer of Dongting Lake.Based on poor mechanic properties,low bearing capacity and difficult construction of the foundation,preparing task and construction scheme were made according to construction conditions.Reverse circulation method with low gear was adopted during construction of large-diameter bored pile which was followed with reverse circulation method to clear bore.Underwater concrete of bored piles were poured by lifting conduit method,while overwater concrete pouring adopted drawing ball technique.According to the inspection when construction was finished,all the fifty-four bored piles reach the requirements of design and standard.更多还原