某不规则超限高层结构优化设计方案探讨

Optimization Design of an Irregular Out-of-code High-rise Structure Scheme

框架-核心筒结构是高层结构常用的结构体系。为满足建筑实现多功能用途,通常在底部楼层开大洞以获得通高大厅,而楼板开大洞会导致结构水平传力受阻,楼层发生刚度突变,易使结构成为超限高层建筑结构。为消除结构薄弱层,改善结构的不规则程度,在原框架-核心筒工程实例的基础上,采用梁上“设缝立柱”形成二次结构对原结构方案进行调整,在6、7度抗震设防条件下,利用SATWE和MIDAS软件对2种结构设计方案进行了弹性和弹塑性状态下抗震性能分析,比较地震作用下结构构件受力、变形及结构构件塑性损伤。经结构指标定量分析发现,在多遇地震下,以“设缝立柱”结构方案可有效降低整体结构扭转变形和控制楼层承载力突变,改善结构不规则程度;罕遇地震作用下,“设缝立柱”方案能够有效缓解构件塑性损伤程度,提高结构抗震性能。本研究可为同类建筑在低烈度区的工程结构设计提供参考和设计建议。

The frame-core tube structure is a prevalent system for high-rise buildings.To meet the multi-functional requiremnts of the building,a large hole is often created on the bottom floor to obtain a high hall.However,such openings in the floor can obstruct the horizontal force transmission within the structure and cause an abrupt change in floor stiffness,potentially making the structure become an out-of-code high-rise building structure.In order to eliminate the weak layer in the structure and improve its irregularity,in the light of the original frame-core tube engineering example,this research adopts a secondary structure formed by“the disconnecting through gap and setting columns”on the beam to adjust the original structural scheme.Under seismic fortification conditions of six and seven degrees,SATWE and MIDAS software were utilized to analyze the seismic performance of the two structural design schemes under both elastic and elastic-plastic conditions.Furthermore,the stress,deformation and plastic damage of structural members under earthquake were compared.Through a quantitative analysis concerning structural indexes,it is found that under frequent earthquakes,the structural scheme of disconnecting through gap and setting columns can effectively minimize the torsional deformation of the whole structure,control the abrupt changes in floor bearing capacity and improve the irregularity of the structure.Under the action of rare earthquakes,this proposed structural scheme can effectively alleviate the plastic damage degree of components and improve the seismic performance of the structure.This study can provide reference and design suggestions for the engineering structure design of similar buildings in low intensity area.