保利增城金融总部办公塔楼结构设计

Structural design of office tower building of Poly Zengcheng Financial Headquarters

保利增城金融总部办公塔楼建筑高335m,为带三道转换桁架的矩形钢管混凝土框架-钢筋混凝土核心筒混合结构。分析环带与伸臂桁架敏感性发现,由于外框柱不连续导致环带与伸臂桁架对刚度贡献较小,故结构不另外对其设置。在节点区混凝土可能存在浇筑不密实,不考虑混凝土有利作用,对转换桁架节点钢材板件有限元分析,通过加厚板件并提高钢号,可实现大震弹性与强节点弱构件性能目标。因建筑效果,首层核心筒外墙在穿梭梯入口处需开大洞,且梯间墙厚由1.2m减薄至0.6m,导致首层外墙薄弱与剪力墙偏心问题,通过壳元偏心应力分析发现,偏心弯矩主要在墙厚变化位置的楼板处平衡,在穿梭梯洞口上设置SRC转换梁,使其在穿梭梯间柱破坏时仍满足大震不屈服,形成二道防线。桁架转换层转角区域径向梁由于其上下柱与环向梁不共面,产生拉力,通过中大震性能验算对其加强。

The office tower of Poly Zengcheng Financial Headquarters has a total height of 335 m and is a composite system of rectangular concrete-filled steel tube frame and reinforced concrete core with three transfer trusses. According to the analysis of sensitivity of belt trusses and outriggers, it is found that due to the discontinuity of the outer columns, the belt truss and outrigger have little contribution to the stiffness of the tower, thus they are not used in this project. In the joint area, casting of concrete may not be dense, thus the beneficial effects of concrete are ignored when analyzing the joint area. The finite element analysis of the transfer truss joint steel plate found that, the performance objectives of elastic performance under large earthquakes and strong connection and weak members can be achieved by increasing the steel plate thickness and steel grade. Due to the architectural requirements, the outer wall of the core on the first floor needs to have a large opening at the entrance of the shuttle elevator, and the wall thickness of the staircase has been reduced from 1.2 m to 0.6 m, which resulting in the weakness of the first floor and the eccentricity of the shear wall. The eccentric stress analysis of shell elements found that the eccentric bending moment was mainly balanced at the floor where the wall thickness changed. The SRC transfer girder was set at the entrance of the shuttle elevator so that it would not yield under large earthquake when the column of the shuttle elevator was damaged, and form a second line of safety. Due to the non-coplanarity of the upper and lower columns and the ring beams, tensile forces are generated in the radial beams in the corner area of the transfer truss floor. Therefore, the radial beams are strengthened under the performance checking of moderate and large earthquakes.