（中国建筑西北设计研究院有限公司， 西安  710018）

［摘要］西咸新区1A楼高位三层整体向东、南方向突出，具有偏心布置、尺寸突变、竖向构件不连续等特性，属于特别不规则建筑，采用的是纯钢框架-中心支撑核心筒-悬挑桁架的结构体系。详细介绍了该项目在超限结构设计中五方面的设计难点：结构的选型、悬挑结构的处理、结构耗能机制及二道防线的计算、关键构件性能目标的确定、人字形中心支撑横梁不平衡力的验算方法等。同时，针对超限专家提出的意见采取了相应的加强措施。

［关键词］中心支撑核心筒； 悬挑桁架； 耗能机制； 结构选型； 人字形中心支撑； 不平衡力验算

中图分类号：TU391文献标识码：A文章编号：1002-848X(2020)14-0020-05

Analysis on difficulties for out-of-code structural design of 1A building in Xi-Xian New Area

ZHANG Tao, WANG Hongchen, CHU Ling

(China Northwest Building Design & Research Institute Co., Ltd., Xi′an 710018, China)

Abstract:The three stories in the high zone of the 1A building in Xi-Xian New Area protrudes to the southeast, with  eccentric layout, abrupt size changes, and vertical component discontinuity. It belongs to a special irregular building and  adopts the pure steel frame, concentrically braced corewall and cantilever truss in the structural system. The design difficulties of the project in five aspects of the out-of-code structural design were introduced in detail, including the selection of the structural system, the treatment of the cantilevered structure, the calculation of the energy dissipation mechanism of the structure and the calculation of the second line of seismic defense, the determination of the performance goals of key components, and the calculation method of the unbalanced force of the herringbone-shaped concentrically braced beam.At the same time, the corresponding strengthening measures were carried out in view of the opinions made by over\|limit experts.

Keywords:concentrically braced corewall; cantilever truss; energy dissipation mechanism; structural system selection; herringbone-shaped concentrically brace; calculation of unbalanced force

作者简介：张涛，硕士，高级工程师，Email：715022465@qq.com。