某高层综合楼改造加固结构设计

Structural Strengthening Design for the Renovation of a High-rise Complex Building

某20层综合楼,使用功能需要将层3,4活荷载标准值由设计时的4kN/m^2提高至10kN/m^2。检测发现,原设计层3,4框架柱的混凝土强度等级为C50,实测值分别为C30,C34;梁、板的混凝土强度等级为C30,实测值为C24。为避免对原有梁、板进行加固,楼板采用柱网间的板下沿对角线设置交叉钢梁加固方案,按构件实测强度进行整体结构分析的结果,对不满足承载力或抗震构造要求的框架柱采用钢构套加固方案。加固施工期间基本不影响相邻楼层的正常使用。

Because of the service function change on the 3rd and 4th floor of a 20-story high-rise complex building,the characteristic value of live load is raised to 10kN/m^2 from 4kN/m^2.In the 3rd and 4th floor,the designed strength grades of concrete for columns is C50,for beams and slabs is C30,nevertheless by means of concrete strength inspection,the actual strength grades for the 3rd and 4th floor columns is C30 and C34 respectively,for beams and slabs is C24.To avoid strengthening the existing beams and slabs,steel beams along the diagonal of the column grid below the slabs were adopted to reinforce the slabs.According to the structural analysis results using the member actual strength,the method of structure member strengthening with steel frame was used to strengthen the columns which do not satisfy the requirements of carrying capacity or details of seismic design.During the strengthening construction,the adjacent floors were still on service.