上海南京东路179号街坊成片保护改建工程结构设计

Structural design of integrated retrofit project of No.179 block Nanjing East Road, Shanghai

上海南京东路179号街坊成片保护改建工程原为4组共7栋建于20世纪20年代的建筑单体,通过改造既有建筑并加建1栋新建筑最终形成4栋新建筑,同时增设一个异形钢结构网壳屋盖将4栋新建筑相连。对于建筑立面和结构体系不得改变的三类优秀历史保护建筑,根据结构鉴定结果,确立了经济合理的改造设计标准,并采用增大截面、粘钢等方式对原结构构件进行加固。对于保留历史建筑,采取仅保留外墙、内部拆除重建的方案;保留的外墙利用带钢筋网片的自密实混凝土内衬墙进行加固,并通过特定的节点构造与内部新建结构连接。通过该节点,外墙在平面内自承重,平面外依靠在新建结构上。针对4栋单体结构动力特性差异较大的问题,提出了一种特殊的隔震支座,支座和主体结构的整体分析表明,该隔震支座减小了主体结构和柔性网壳在水平荷载作用下的相互影响,也满足了屋盖在风载作用下的抗拉性能要求。

The integrated retrofit project of No.179 block Nanjing East Road, Shanghai were 4 groups of 7 buildings built in 1920 s originally. Through retrofit of the existing buildings and increase of a new building, 4 new buildings were formed. The 4 new buildings were connected by adding an irregular steel shell roof. According to the structure detection results, the economic and reasonable renovation design criterion was established for the class Ⅲ outstanding historical preserved building. The building elevation and structural systems cannot be changed, and the original structure members were strengthened by increasing section and bonding steel plates. For the preservation of historical buildings, the plan was adopted that the outside walls were retained and the inside structure was demolished and reconstructed. The reserved outside walls were strengthened by the self-compacting concrete lining walls with reinforced mesh and connected to the new internal structure by a particular node. The outside walls were self-bearing of the weight in the plane and attached to the new structure out of the plane with the nodes. In view of the large differences in the dynamic characteristics of the 4 structures, a particular isolation bearing was proposed. The holistic modeling analysis of the main structure with the bearings indicates that the interrelation of main structure and the flexible shell under lateral loads is reduced effectively, and the tension performance requirement of the steel roof under wind load is also satisfied by the proposed bearing.