下穿河道和桥梁基础的某地铁车站设计方案探讨

南宁市轨道交通1号线石埠站下穿石埠河和石埠河桥基础,因受工程条件制约而采用明挖法施工,为此需解决河道导流、基坑支护和桥梁还建等三个设计难题。根据现场环境条件,分析三者之间的相互制约关系,提出"围堰+导流管导流、锚索+内支撑基坑组合支护体系和箱涵还建桥梁"的综合设计方案,并对具体的设计方法进行介绍,指出各项设计的要点。该设计方案的实施使得地铁车站施工和桥梁还建施工顺利完成,并确保河道的行洪能力,达到预期设计效果,表明该方案是合理可行的。

Discussion on Design of a Metro Station Passing Underneath Riverway and Bridge Foundation

Based on the Nanning subway Line 1,the station of Shibu is designed to pass underneathShibu river and its bridge foundation. Due to the constraint of engineering conditions,the cut-andcover method is adopted to resolve three designproblems including river diversion,foundation ditch support and re-construction of bridges. According to the in-situ circumstances,the correlation between the three is analyzed,and an integrated design scheme is proposed,which is composed of cofferdam plus diversion by draft tube,anchor cable plus internal support system and construction of bridges with box girder. Subsequently,the specific design approach is introduced and the main points of design for each item are put forward. The construction of the metro station and re-construction of bridges are successfully implemented due to the application of this design scheme and the designed flood carrying capacity is guaranteed,which demonstrates the rationality and feasibility of the scheme.