南京地铁三号线主动桩基托换工程设计

Design of Active Pile Foundation Underpinning Project of Nanjing Metro No.3 Line

龙蟠南路高架桥是南京市南北向重要通道,交通繁忙。地铁三号线下穿位于雨花站至卡子门站区间,地铁隧道左线穿越龙蟠南路高架桥侵入桥台桩基;隧道右线穿越龙蟠南路高架桥侵入高填土路基挡土墙预制方桩,直接截取桩基对地铁盾构施工及桥梁结构本身受力存在安全隐患,需对其主动桩基托换处理。该文介绍了其工程设计。为维持高架桥正常通车,不中断交通,分别从劲性托换梁方案和承台补偿方案进行对比分析,优化选定了承台补偿方案,并对承台补偿方案的整体结构计算分析与设计作了论述,有效地解决了桥台主动桩基托换难题,具有较好的应用价值。

Longpan(S) Road Viaduct is an important south – north passage of Nanjing City with the busy traffic.Metro No.3 Line underpasses the area located between Yuhua Station and Kazimen Station.The left tunnel of the metro passes through Longpan(S) Road Viaduct intruded into the pile foundation of the abutment,and the right tunnel of the metro passes through Longpan(S) Road Viaduct intruded into the prefabricated square piles of retaining wall for the high-filling soil roadbed.The direct cutting up of pile foundation has potential safety problem for the shield construction of metro and its stress of bridge structure.It is required to carry out the underpinning treatment of active pile foundation.The article introduces its engineering design.In order to continue the normal traffic of viaduct without interrupting traffic,the article compares and analyzes the stiff underpinning beam scheme and base slab compensation scheme,optimizes and selects the base slab compensation scheme,discusses the calculation analysis and design of the integral structure of base slab compensation scheme efficiently to solve the active pile foundation underpinning difficulty of the bridge abutment,which have better application value.