高层建筑地下室的抗浮设计方案研究

Research on anti-floating design scheme of basement of high-rise building

以郑州某高层办公楼地下室为研究对象,探讨了抗浮设计中关键参数的取值和依据。同时建立了综合考虑上部结构、筏板与抗浮锚杆的有限元模型,对抗浮锚杆的抗拔刚度、布置方案、上部结构刚度等因素进行了多参数分析。结果表明:常规设计时采用的抗浮锚杆根数简化计算方法的经济性与安全性均较差,应采用考虑多因素的整体分析模型,确保地下室结构抗浮设计安全、经济;抗浮锚杆抗拔刚度对地下室抗浮设计影响较大,应通过抗浮锚杆承载力试验推导出实际刚度作为设计输入条件,从而达到地下室抗浮设计的优化;抗浮设计依赖抗浮锚杆抗拔与筏板弯曲共同作用,本质上是筏板弯曲配筋设计与抗浮锚杆设置两者平衡的过程。

Taking the basement of a high-rise office building in Zhengzhou as a research object, the values and basis of key parameters in anti-floating design were discussed. At the same time, a finite element model that comprehensively considers the above-ground structure, baseplates and anti-floating anchors was established. The multi-parameter analysis of the anti-floating anchor′s pull stiffness, layout scheme, and above-ground structure stiffness was performed. The results show that the simplified calculation method of the number of anti-floating anchors is without advantage in economics and safety in conventional design, and the overall analysis model considering multiple factors should be adopted to ensure the safety and economy of the anti-floating design of the basement structure. The pull stiffness of the anti-floating anchors has a greater impact on the anti-floating design of the basement. The actual stiffness should be derived from the anti-floating anchor bearing capacity test as the design input condition to achieve the optimization of the basement anti-floating design.The anti-floating design relies on the joint action of the anti-floating anchor pull resistance and the baseplate bending, which is essentially a process of balancing the design of the raft bending reinforcement and the anti-floating anchor setting.