Overview of Performance-Based Design of Building Structures in China 中国建筑结构性能化抗震设计概况 Abstract Guo-Qiang Li Yan-Bin Xu The development history, the cur

Transcription

1 ctbuh.org/papers Title: Authors: Subjects: Keywords: Overview of Performance-Based Design of Building Structures in China Guo-Qiang Li, Professor, Tongji University Yan-Bin Xu, Engineering Master Candidate, Tongji University Fei-Fei Sun, Research Professor, Tongji University Structural Engineering Code Compliance Performance Based Design Publication Date: 2012 Original Publication: Paper Type: CTBUH th World Congress, Shanghai 1. Book chapter/part chapter 2. Journal paper 3. Conference proceeding 4. Unpublished conference paper 5. Magazine article 6. Unpublished Council on Tall Buildings and Urban Habitat / Guo-Qiang Li; Yan-Bin Xu; Fei-Fei Sun

2 Overview of Performance-Based Design of Building Structures in China 中国建筑结构性能化抗震设计概况 Abstract Guo-Qiang Li Yan-Bin Xu The development history, the current situation and the future of performance-based seismic design in China are presented. The evolution of performance-based seismic design specified in the Chinese codes for seismic design of 5 editions (Edition 1974, 1978, 1989, 2001 and 2010) are introduced and compared. This paper details the provisions of performance-based seismic design in different codes ( Code for Design of Buildings and Technical Specification for Concrete Structures of Tall Building ), which presents the concepts and methods of performance-based seismic design adopted in Chinese codes. Lastly, according to those mentioned above, this paper points out the imperfections of current performance-based seismic design in China and proposes the possible direction for further improvement. Keywords: Performance-based seismic design; Out-of-codes High-rise Building Structures 摘要 Fei-Fei Sun Guo-Qiang Li, Yan-Bin Xu & Fei-Fei Sun Building of Civil Engineering, Tongji University 1239 Siping Road Shanghai China tel ( 电话 ): fax ( 传真 ): ( 电子邮箱 ): gqli@tongji.edu.cn, xuyanbin @163.com, ffsun@tongji.edu.cn Prof. Guo Qiang Li is currently a professor of structural engineering at the College of Civil Engineering in Tongji University and the director of Research Center of Education Ministry for Steel Construction. He is also a vice-chairman of China Association of Construction Standardization and the Chairman of China Association for Fire-Resistance of Steel Construction. His main research topics are on behavior of multi-story steel buildings and earthquake- and fire-resistance of steel structures. He is an author of 12 technical books and more than 400 journal papers in English and Chinese on his research topics. 李国强, 目前担任同济大学土木工程学院结构工程教授, 教育部钢结构工程研究中心主任 另兼任中国工程建设标准化协会副理事长, 中国钢结构协会钢结构防火与防腐分会理事长 主要研究领域为多高层建筑钢结构及钢结构抗震与抗火 出版研究专著 12 部, 发表中英文学术期刊论文 400 多篇 Mr. Yanbin Xu graduated from the College of Civil Engineering, Tongji University in July 2011 with acquisition of his Engineering Bachelor s degree. Studying now for Engineering Master s degree since September 2011 in the research area of high-rise buildings of steel and steel structure fire resistance. 许炎彬,2007 年 9 月进入同济大学土木工程学院就读,2011 年 7 月毕业, 获工学学士学位,2011 年 9 月进入同济大学建筑工程系, 攻读工学硕士学位 现研究方向为多高层建筑钢结构及钢结构抗火 Dr. Feifei Sun is a research professor of Advanced Research Institute of Civil Engineering at Tongji University. He acts as a member of Resistance of Tall Buildings at Branch of Proof and Disaster Reduction of China Building Society. His main research topics are on behaviour of multi-story steel buildings and earthquake-resistance of steel structures. 孙飞飞博士是同济大学土木工程系的高等研究所的一名教授, 同时也是中国建筑协会防震减灾分会高层建筑抗震方面的委员 孙先生主要的研究课题为多层钢结构建筑的表现和钢结构的抗震性 本文探讨了中国性能化抗震设计历史 现状及未来 首先, 针对不同时期的五个版本的抗震规范, 明确了性能化抗震设计出现 发展 变化的历程 其次, 介绍了性能化抗震设计在相关规范 建筑抗震规范 高层建筑混凝土结构技术规范 中的内容, 并对中国规范范围的性能化抗震设计要求做了介绍 最后, 指出了中国性能化抗震设计尚存的问题并提出了对未来的改进提出了建议 关键词 : 性能化设计超限高层建筑 Introduction In China, 5 editions of seismic design codes have been promulgated so far. These are Antiseismic Design Code of Industrial and Civil Building (Trial) TJ 11-74, Anti-seismic Design Code of Industrial and Civil Building TJ 11-78, Specifications for anti-seismic construction design GBJ11-89 (implemented since 1990, partially revised in 1993), Code for Design of Buildings GB (partially revised after the 2008 Wenchuan ) and Code for Design of Buildings GB , hereinafter respectively referred to as Code74, Code78, Code89, Code01 and Code10. In Chinese codes, fortification intensity is regarded as criterion of seismic design requirements, corresponding to basic seismic intensity. The basic seismic intensity of a certain region in China is defined as the impact of the earthquake with 10 percent probability of exceedance in 50 years, divided into 12 degrees, demarcated by maximum ground acceleration and the earthquake impact or damage extent on landform or buildings (Table 1). Code74 and Code78 use single seismic Introduction 在中国, 至今共颁布了 5 个版本的建筑抗震设计规范, 分别是 : 工业与民用建筑抗震设计规范 ( 试行 )TJ 工业与民用建筑抗震设计规范 TJ 建筑抗震设计规范 GBJ 11 89( 于 1990 年开始实施,1993 年作局部修订 ) 建筑抗震设计规范 GB (2008 年汶川地震后作了局部修订 ) 建筑抗震设计规范 GB , 以下分别简称 74 规范 78 规范 89 规范 01 规范和 10 规范 中国以设防烈度作为建筑结构抗震设计要求的基准, 而设防烈度一般情况下与地震基本烈度相对应 中国任一地区的地震基本烈度的定义为该地区 50 年超越概率为 10% 的地震影响程度, 共分为 12 度, 以地面最大加速度 地震对地貌或建筑物的影响或破坏程度来标定 ( 表 1) 中国 74 规范和 78 规范均采用单一水准设防 ( 表 1), 规定了 7 度和 7 度以上设防, 均要求结构在设防水准地震下不坏, 即控制地震下的结构变形和保证结构足够的抗震承载力, 在抗震设计的概念上这两部规范没有实质性区别, 在前者中规定, 对于一般建筑物, 设计烈度可比基本烈度降低一度, 基本烈度为 7 度时不降低 ; 在 1976 年 656

3 demand level, see Table 1, taking design intensity of 7 degrees and above into consideration, requesting no damage under earthquakes of fortification level, which is to control structural deformation under earthquake and to ensure adequate structural seismic bearing capacity. In the former, for general buildings, the design intensity is one degree lower than the basic seismic intensity (not when the basic seismic intensity is 7 degrees) ; In the latter which was promulgated after the 1976 Tangshan, the design intensity is equal to the basic seismic intensity. In Code89, three-levels performance objectives of seismic design of buildings as no damage under minor earthquakes, repairable under moderate earthquakes, no collapse under severe earthquakes was proposed, which means or applicable without repair when suffered from frequent earthquake (minor earthquake), (10 percent probability of exceedance in 50 years); Applicable after normal repair when suffered from earthquake action of fortification intensity; No collapse or serious damage that can create hazard to life safety when suffered from predicted rare earthquake (severe earthquake), (2-3 percent probability of exceedance in 50 years). In Code89, to realize the three-levels of performance objectives, the two-steps seismic design method was developed, detailed as follows: 1st step, using ground motion parameter (ground motion peak acceleration and characteristic period of earthquake motion response spectrum) of minor earthquake, firstly calculate the elastic relative inter-story drift to be less than the limit value, in order to satisfy the requirement of no breaking for nonstructural component and no damage for structure of first level; secondly, combining the effect of earthquake action with effect of other loads to check the member bearing capacity, in order to satisfy the bearing capacity requirements of the first level. 2nd step, using ground motion parameter of severe earthquake, calculate the elastic-plastic relative inter-story drift to be less than the limit value, in order to satisfy the requirement of no collapse of building structure of third level. Code89 is one of the first codes in which the performance-based seismic design (hereinafter referred to as PBSD) was introduced. However, imperfections exists: 1) The requirements for no damage under minor earthquakes and no collapse under severe earthquakes were given, see Table 1, but not for the repairable under moderate earthquakes ; 2) In member bearing capacity checking of no damage under minor earthquakes, partial factor of earthquake action larger than 1.0 is introduced, thus the earthquake action is not exactly the same as that of minor earthquake with 10 percent probability of exceedance in 50 years. Code74 74 规范 Code78 78 规范 Code89 89 规范 Code 规范 Code 规范 First Level (Minor ) 第一水准 ( 小震 ) Member Bearing capacity Checking 构件承载力验算 Second Level (Moderate ) 第二水准 ( 中震 ) Third Level (Severe ) 第三水准 ( 大震 ) Member Bearing capacity Checking 构件承载力验算 1) Structural Elastic Structural Elastic-Plastic Deformation Checking Deformation Checking 结构弹性变形验算 结构弹塑性变形验算 2) Member Bearing capacity Checking 构件承载力验算 Table 1. design requirements of building structures of China 表 1. 中国建筑结构抗震设计要求 唐山大地震之后, 经过局部修改, 颁布了后者, 规定一般建筑物的设防烈度按基本烈度采用 在随后的 89 规范中, 中国即提出了 小震不坏 中震可修 大震不倒 的建筑结构抗震设计三个水准性能化目标, 即要求建筑结构 当遭受低于本地区设防烈度的多遇地震 ( 即小震 ) 影响时 (50 年超越概率为 10%), 一般不受损坏或不需修理仍可继续使用, 当遭受本地区设防烈度的地震影响时, 可能损坏, 经一般修理或不需修理仍可继续使用, 当遭受高于本地区设防烈度的预估的罕遇地震 ( 即大震 ) 影响时 (50 年超越概率为 2%-3%), 不致倒塌或发生危及生命的严重破坏 89 规范是通过 两阶段设计, 试图实现上述三水准抗震设防目标的 : 第一阶段设计, 采用 小震 地震动参数 ( 地震动峰值加速度和地震动反应谱特征周期 ), 先计算出结构的弹性层间位移角, 使其不超过规定的限值, 从而满足第一水准建筑结构的非结构构件不坏或结构不受损的要求 ; 然后计算出结构在弹性状态下的地震作用效应, 与风 重力等荷载效应组合, 进行结构构件承载力验算, 从而满足第一水准的结构承载力要求 第二阶段设计, 采用 大震 地震动参数, 计算出结构的弹塑性层间位移角, 使之小于规范规定的限值, 从而满足第三水准的防止建筑倒塌的要求 中国在 1989 年即颁布实施的 89 规范应该是世界上较早引入性能化思想的建筑抗震设计国家标准, 但该规范的缺陷是 :1) 规范只有 小震不坏 和 大震不倒 的性能设计要求 ( 见表 1), 而没有 中震可修 的性能设计要求 ;2) 在 小震不坏 的结构承载力验算要求中, 由于引入了大于 1 的地震作用分项系数, 因此进行结构承载力验算所采用的地震作用与 50 年超越概率为 10% 所对应的小震并不一致 Design Provisions of PBSD in China Provisions in Code for Design of Buildings GB In Code10, requirements of PBSD are specified in 3.10, titled as Performance-Based Design of Buildings. As it refers, when PBSD is adopted in designing, the objectives shall be evaluated both technically and economically, according to fortification intensity, site condition, structure type and irregularity, functional requirements of building and ancillary facility, investment, post-earthquake loss and repair cost. Objectives of PBSD could be targeted respectively to overall structure, parts of the structure, key members, important members, secondary members, construction members and electromechanical equipment. 中国建筑结构性能化抗震设计规定 GB 建筑抗震设计规范 的规定 GB 建筑抗震设计规范 3.10 节题为 建筑抗震性能化设计 规范中具体地指出, 当建筑结构采用抗震性能化设计时, 应根据其设防烈度 场地条件 结构类型和不规则性, 建筑使用功能和附属设施功能的要求 投资大小 震后损失和修复难易程度等, 对选定的抗震性能目标提出技术和经济可行性综合分析和论证 ; 建筑结构的抗震性能化设计, 应根据实际需要和可能, 具有针对性 : 可分别选定针对整个结构 结构的局部部位或关键部位 结构的关键部件 重要构件 次要构件以及建筑构件和机电设备支座的性能目标 建筑结构抗震性能化设计应符合如下步骤 : 首先选定地震动水准, 其次选定性能目标, 随后选定性能设计指标 可供选择的建筑抗震性能化设计的预期性能目标分为 1/2/3/4, 如表 2 所示 657

4 The PBSD steps are: 1) Select the seismic ground motion level; 2) Select the performance objectives; 3) Select the performance-based design demand. The anticipated performance objectives of PBSD dividing into 1/2/3/4 to choose from are listed in Table 2. The performance-based design demands on bearing capacity, inter-story drift and seismic grade of construction measures are then specified to realize the performance objectives. Provisions in Technical specification for concrete structures of tall building (JGJ3-2010) Similar to Code GB , the performance objective of tall buildings is divided into four grades named A/B/C/D. In addition, the aseismic performance level is divided into 5 levels named 1/2/3/4/5. Each performance objective corresponds to a group of aseismic performances under different earthquake levels, see Table 3. design provisions of out-of-codes high-rise buildings In China, for high-rise buildings over the limits of the relevant codes, we are naming this group out-of-codes high-rise buildings. Out-ofcodes high-rise buildings are divided into two types: 1) building height exceeding limits and 2) structure regularity exceeding limits. For the out-of-codes high-rise buildings, seismic tests shall be conducted when necessary and a peer review for the seismic design scheme shall be adopted. The additional requirements for design of out-of-codes high-rise buildings mainly are: Using two independent structure analysis software programs to proceed the seismic calculations, respectively; Elastic time-history analysis demanded; Elastic-plastic time-history analysis demanded for buildings over 200m; Using two independent structure analysis programs to proceed elastic-plastic time-history analysis for buildings over 300m; Considering the elastic deformation of floor. Conclusions and Suggestions Primary Achievements From the translation of Codes for Buildings in Zones of the former Soviet Union in 1955 to the publication of Code for Design of Buildings GB in 2010 with the proposition of the PBSD concept, significant achievements have been gained. These are: Level 地震水准 Frequent 多遇地震 Design 设防地震 Rare 罕遇地震 1 性能 1, in normal use, 正常使用 Nearly perfect, maintenance 基本, 检修后继续使用 2 性能 2 Nearly perfect, maintenance 基本, 检修后继续使用 Minor damage, repair 轻微至中等破坏, 修复后继续使用 3 性能 3 Minor damage, slight repair 轻微损坏, 简单修理后继续使用 Applicable after strengthening 其破坏需加固后继续使用 4 性能 4 Minor to moderate damage, deformation < 3 [ΔU e ] 轻微至接近中等损坏变形 < 3 [ΔU e ] Serious damage, overhaul 接近严重破坏, 大修后继续使用 Table 2. Anticipated performance objectives of PBSD for buildings 表 2. 建筑抗震性能化设计的预期性能目标 Note: ΔU e : maximum elastic inter-story drift caused by standard value of frequent earthquake action. 注 :ΔU e : 多遇地震作用标准值产生的楼层内最大的弹性层间位移 以上性能目标是一般意义上的要求, 具体针对承载力 层间位移和抗震等级, 规范还给出了更为细致的要求 高层建筑混凝土结构技术规程 (JGJ3-2010) 的规定与 GB 类似, 在 JGJ 中将高层建筑结构抗震性能目标分为 A B C D 共四个等级, 将高层建筑结构抗震性能水准分为 共五个水准, 每个等级的结构性能目标均与一组不同地震水准下的结构抗震性能水准对应见表 3 超限高层建筑的抗震设计规定中国对超出有关规范抗震设计限定的高层建筑称之为超限高层建筑 超限高层建筑分为建筑高度超限和结构规则性超限两类 超限高层建筑抗震设计时, 除须满足中国有关规范所有抗震要求外, 在结构抗震计算还需满足额外要求, 需要通过抗震专项专家审查的方式评判其抗震设计能否达到预定的抗震性能目标要求 超限高层建筑抗震计算的额外要求主要有 : 采用两个独立的结构分析软件进行结构抗震计算 ; 进行结构弹性时程分析 ; 高度超过 200m 的超限高层建筑, 应进行弹性时程分析 ; 高度超过 300m 的超限高层建筑, 应采用两个独立的软件进行弹塑性时程分析 ; 应考虑楼板的弹性变形影响 Performance Level 性能水准 Macroscopic Damage 宏观受损程度, no damage Nearly perfect, minor damage 基本, 轻微损坏 Slight damage 轻度损坏 Moderate damage 中度损坏 Quite serious damage 比较严重损坏 Key Member 关键构件 Minor damage 轻微损坏 Slight damage 轻度损坏 Moderate damage 中度损坏 Table 3. Anticipated post-earthquake performances 表 3. 各性能水准结构预期的震后性能状况 Damage Position 损坏部位 General Vertical Member No Damage 普通竖向构件 耗能构件 Minor damage 轻微损坏 Moderate damage of certain members 部分构件中度损坏 Quite serious damage of certain members 部分构件比较严重损坏 Minor damage 轻微至接近中等损 Slight damage, partially moderate damage 轻度损坏, 部分中度损坏 Moderate damage, partially quite serious damage 中度损坏, 部分比较严重损坏 Quite serious damage 比较严重损坏 Possibility to Continue Using 继续使用的可能性 Applicable without repair 不许修理即可继续使用 Applicable after slight repair 稍加修理即可继续使用 Applicable after repair 一般修理后可继续使用 Applicable after restoration or strengthening 修复或加固后可继续使用 Needy of overhaul 需排险大修 658

5 Three-levels of performance objectives for seismic design are no damage under minor earthquakes, repairable under moderate earthquakes, no collapse under severe earthquakes has been proposed.these include consideration for function, economy and life safety under earthquake, which is scientificly based; Different performance objectives are allowed to be adopted for different buildings, and performance-based aseismic requirements are proposed for different members; Additional performance-based aseismic requirements and judgement requirements are proposed for out-of-codes highrise buildings. Existing Problems A few problems exist requiring further development. They are: Performance-based aseismic requirements of structural bearing capacity are considered under elastic minor earthquake action, with no distinction to different ductile structures. In fact, dissipative capacity, which is closely related to ductile deformation ability, is more suitable in judging the structural aseismic capacity. For the structures of the same bearing capacity, there is a positive correlation between dissipative capacity and ductile deformation ability; that is to say, for the structures with the same performance-based aseismic requirement, the bearing capacity can be lower while the ductile deformability is higher; Construction detail requirements are related to ductile deformation ability.in the codes, the construction detail requirements are highly correlated to seismic fortification intensity and structure height; It relies mainly on bearing capacity but not the member ductile deformation ability in defining the different seismic performance levels of members. Improvement Suggestions Three-levels of performance objectives of seismic design shall be adjusted and clarified as: ensuring no damage under minor earthquakes by checking elastic deformation, ensuring repairable under moderate earthquakes by checking bearing capacity while determining the earthquake action with consideration to ductile deformation ability of different structures, and determining construction requirements according to structural ductile deformability, ensuring no collapse under severe earthquakes by checking elastic-plastic deformation. The definition for different seismic performance levels of members shall rely on ductile deformation ability aside from the bearing capacity. Appendix Basic design parameters specified in the codes of seismic design in China In Code89, the seismic influence is characterized mainly by the seismic intensity zoning of that time, and the characteristic period was brought in to reflect the influence to the design response spectrum caused by near and distant earthquakes. Since Code01, the basic design acceleration of ground motion and the characteristic period were brought in, see Table 4 and 5. 总结及建议 主要成就我国从 1955 年开始翻译出版苏联 地震区建筑规范, 到 2010 年出版 建筑抗震设计规范 GB , 正式提出性能化抗震设计的明确理念, 在建筑结构性能化抗震设计方面取得了可观的成就 : 提出了 小震不坏 中震可修 大震不倒 的建筑结构抗震设计三水准性能化目标 该目标兼顾了建筑功能在地震后的持续 建筑结构抗震的经济性 以及建筑结构应保证地震下的人员安全的综合要求, 具有科学性 ; 允许不同建筑抗震设计采用不同的性能化目标, 并对于不同性能化目标的建筑的构件, 提出了明确的不同构件下抗震性能设计要求 对于超限高层建筑, 提出额外的抗震性能设计与评审要求 存在问题目前中国建筑结构性能化抗震设计主要的问题体现在 : 结构承载力性能要求按小震弹性地震作用考虑, 不考虑不同延性结构对结构抗震承载力性能要求的区别 实际上, 结构延性变形抗震能力的衡量标准是结构耗能能力时比较合适来判断结构的抗震性能, 而结构耗能能力与结构承载能力和延性变形能力有关, 结构承载能力相同时, 结构延性变形能力越大, 耗能能力越大, 换言之, 在相同的抗震能力 ( 或耗能能力 ) 要求下, 结构延性变形能力越大, 结构承载能力要求可降低 规范中结构构造要求与结构延性变形能力有关, 但规范中构造要求与抗震设防烈度及结构高度相关, 而不与结构延性变形能力要求相关 对构件不同抗震性能水准的定义主要依据承载力水准, 而不考虑构件延性变形能力的不同 改进建议调整并明确建筑结构抗震设计三水准性能化目标的具体要求为 : 验算结构弹性变形, 保证 小震不坏 ; 考虑不同结构延性变形能力确定地震作用 ( 承载力要求 ), 验算结构承载力, 并根据结构延性变形能力要求确定结构构造要求, 以保证 中震可修 ; 验算结构弹塑性变形, 保证 大震不倒 对构件不同抗震性能水准的定义, 除依据承载力水准外, 应更主要依据考虑构件延性变形能力 附录 中国建筑抗震设计规范规定的设防基本参数对建筑所在地区遭受的地震影响,89 规范主要借助当时的地震烈度区划, 确定设防基本地震加速度值, 并引入了特征周期 ( 反映震中距 场地类别等因素影响的设计反应谱下降段起始点对应的周期值 ), 反映近震和远震对设计反应谱的影响 从 01 规范开始, 引入了 设计基本地震加速度 和 特征周期 表征设防基本参数, 如表 4 和表 5 所示 中国建筑抗震设计规范构件承载力验算要求在 10 规范中, 结构构件的截面抗震验算采用下列设计表达式 : Fortification Intensity 抗震设防烈度 Basic design acceleration of ground motion 设防基本地震加速度值 g 0.10(0.15)g 0.20(0.30)g 0.40g Table 4. Relationship between the intensity and basic design acceleration of ground motion 表 4. 抗震设防烈度和设计基本地震加速度值的对应关系 659

6 Checking requirements of member bearing capacity in codes of seismic design in China In Code10, the checking of seismic resistance of cross section shall be made using the following design expression: where: γ RE aseismic capacity factor, less than 1.0; R design value of bearing capacity of the structural member. S design value of the combination of inner forces, which shall be determined by the following equation: γ G partial factor of gravity load, which shall be taken as 1.2 in ordinary conditions; when the effect of gravity load is favorable to the bearing capacity of the member, such factor shall not greater than 1.0; γ Eh, γ Ev partial factors for horizontal and vertical earthquake action respectively, see Table 6; γ w partial factor of wind load, which shall be taken as 1.4; S GE effects for representative value of gravity load; S Eh effects for characteristic value of earthquake action in horizontal direction; S Evk effects for characteristic value of earthquake action in vertical direction; S wk effects for characteristic value of wind load; ψ w factor for combination value of wind load, which shall be taken as 0.0 for ordinary structures, and taken as 0.2 for tall building structures that the wind load is the controlling load. checking for deformation of codes of seismic design in China In Code10, elastic deformation checking and elastic-plastic deformation checking shall be made, and the maximum elastic interstory drift shall comply with the following requirement: Design Group 设计地震分组 1st Group 第一组 2nd Group 第二组 3rd Group 第三组 Table 5. Characteristic period value (s) 表 5. 设计特征周期值 (s) Site-Class 场地类别 I 0 I 1 II III IV γ RE 承载力抗震调整系数, 小于 1; R 结构构件承载力设计值 ; S 结构构件内力组合的设计值, 按下式计算 γ G 重力荷载分项系数, 一般情况应采用 1.2, 当重力荷载效应对构件承载能力有利时, 不应大于 1.0; γ Eh, γ Ev 分别为水平 竖向地震作用分项系数, 应按表 6 采用 ; γ w 风荷载分项系数, 应采用 1.4; S GE 重力荷载代表值的效应 ; S Eh 水平地震作用标准值的效应, 尚应乘以相应的增大系数或调整系数 ; S Evk 竖向地震作用标准值的效应, 尚应乘以相应的增大系数或调整系数 ; S wk 风荷载标准值的效应 ; ψ w 风荷载组合值系数, 一般结构取 0.0, 风荷载起控制作用的建筑应采用 0.20 中国建筑抗震设计规范结构变形验算要求在 10 规范中, 多遇地震下弹性变形验算和罕遇地震下薄弱层 ( 部位 ) 弹塑性变形验算, 应符合下式 : where: Δu e elastic inter-story drift caused by the characteristic value of the frequent earthquake action; Δu p elastic-plastic inter-story drift; [θ e ] Limit value of elastic-plastic relative inter-story drift, see Table 7; 式中 : Δu e 多遇地震作用标准值产生的楼层内最大的弹性层间位移 ; Δu p 弹性层间位移角 ; [θ e ] 弹性层间位移角限值, 宜按表 7 采用 ; [θ p ] 弹塑性层间位移角限值, 可按表 7 采用, 对钢筋混凝土框架 Action 地震作用 γ Eh γ Ev Material 材料 Type of Structure 结构类型 [θ e ] [θ p ] Only horizontal earthquake action Frame 1/550 1/50 仅计算水平地震作用 Only vertical earthquake action 仅计算竖向地震作用 Both horizontal and vertical earthquake action (horizontal predominant) 同时计算水平与竖向地震作用 ( 水平地震为主 ) Both horizontal and vertical earthquake action (vertical predominant) 同时计算水平与竖向地震作用 ( 竖向地震为主 ) Table 6. Partial factor of earthquake action 表 6. 地震作用分项系数 Reinforced Concrete 钢筋混凝土 Steel 钢 钢筋混凝土框架 Frame-wall, slab-column-wall, frame-core-tube 钢筋混凝土框架 - 抗震墙 板柱 - 抗震墙 框架 - 核心筒 Wall, tube-in-tube 钢筋混凝土抗震墙 筒中筒 Multi-story and tall structures 多 高层钢结构 Table 7. Limit value of relative inter-story drift 表 7. 层间位移角限值 1/800 1/100 1/1000 1/120 1/250 1/50 660

7 [θ p ] limit value of elastic-plastic relative inter-story drift, which may be taken in accordance with Table 7; h height of story. Foundation Interaction For reinforced concrete tall buildings using box-type or a relatively rigid raft foundation or box-pile foundation for intensity 8 and 9 and with site-class III or IV, and the fundamental period of the structure is within the scope of 1.2 to 1.5 times of the characteristic period of the site, if the foundation interaction is to be considered, the horizontal shear forces assumed for the rigid base may be reduced, and the story drift may be calculated according to the reduced shear force. Damping adopted in different editions of code (Table 8) Nonstructural Systems Gravity of nonstructural components and electromechanical components permanently attached to structures shall be taken into consideration in earthquake action calculations. Stiffness of members with a flexible connection can be neglected. For rigid nonstructural components implanted into the plane of lateral force resisting members, influence of its stiffness shall be taken into consideration. Generally, its earthquake resistant bearing capacity shall not be taken into consideration unless specific construction measures are adopted. For structural members which support nonstructural components, the effect of earthquake action of the latter shall be treated as an additional action. Inspection Procedures For general building structures, peer review shall be conducted by a qualified drawing review firm after the design has been completed. For out-of-codes high-rise buildings, peer review shall be conducted by the Expert Committee, organized by local or national construction department, according to the Management Provisions for design of Out-of-codes High-rise Building Structures. Concrete Structure 混凝土结构 Masonry Structure 砌体结构 Code10 10 规范 Table 8. Damping adopted in Code10 表 8.10 规范中对阻尼的考虑 Steel Structure 钢结构 结构, 当轴压比小于 0.40 时, 可提高 10%; h 计算楼层层高 基础的相互作用 8 度和 9 度时建造于 Ⅲ Ⅳ 类场地, 采用箱基 刚性较好的筏基和桩箱联合基础的钢筋混凝土高层建筑, 当结构基本自振周期处于特征周期的 1.2 倍至 5 倍范围时, 若计入地基与结构动力相互作用的影响, 其层间变形可按折减后的楼层剪力计算 抗震设计中对阻尼的考虑 ( 表 8) Frequent Height 50m 高度 50m 多遇地震 50m< Height <200m 50m< 高度 <200m Height 200m 高度 200m Rare 罕遇地震 非结构系统地震作用计算时, 应计入支承于结构构件的建筑构件和建筑附属机电设备的重力 对柔性连接的建筑构件, 可不计入刚度 ; 对嵌入抗侧力构件平面内的刚性建筑非结构构件, 应计入其刚度影响, 可采用周期调整等简化方法 ; 一般情况下不应计入其抗震承载力, 当有专门的构造措施时, 尚可按有关规定计入其抗震承载力 支承非结构构件的结构构件, 应将非结构构件地震作用效应作为附加作用对待 复核程序对于一般建筑结构, 在完成设计之后, 须由第三方有资质的审图公司对设计图纸进行审核 ; 对于超限高层建筑, 则应根据超限高层建筑工程抗震设防管理规定, 由当地建设部门组织专家委员进行抗震设防专项审查