(1 泰禾集团设计研发部, 北京 100022; 2 约翰马丁工程顾问 (北京) 有限公司, 北京 100020;3 福建省万博宇建设技术开发有限公司, 厦门 361009)

摘要: 从钢筋或型钢与混凝土间的界面性能、中震可修验算方法、受剪计算模式、可能的破坏模式、构件延性、截面设计等方面研究了超限高层结构中小偏心受拉混凝土(组合)框架柱名义组合应力的控制方法和标准。 结果表明:型钢对界面粘结的需求较钢筋低,会较早地参与工作从而减小混凝土部分的拉应力水平;由《高层建筑混凝土结构技术规程》(JGJ 3—2010)方法计算所得名义拉应力限值对应着混凝土充分开裂而退出工作这一物理状态,属于正常使用极限状态的验算范畴;本文建议的名义组合应力方法适用于中震可修或偶遇风压下的可修验算,名义拉应力控制方法或名义剪应力控制方法均为这种方法的特例,名义拉应力和名义剪应力限值在非地震工况下分别可取 2. 5ftk 和0. 5ftk,在地震工况下分别可取 2ftk 和 0. 4ftk,当所受剪力较小时可直接采用名义拉应力控制方法;当名义拉应力达到上述限值时,宜考虑纵筋直接受剪的破坏模式,当超过上述限值时,属于承载能力极限状态验算范畴,宜计算钢筋或钢板的组合应力,同时应考虑稳定性验算。 最后,以一实际工程为例,验证了本文建议方法和限值的可行性。

关键词: 混凝土框架柱; 组合框架柱; 小偏心受拉; 名义拉应力; 名义剪应力; 名义组合应力

中图分类号:TU398,TU318 文献标志码:A 文章编号:1002-848X(2022)13-0054-08

DOI:10. 19701 / j. jzjg. 20181387

Research on nominal tensile stress controlling method of concrete or composite small eccentric tension frame column in code-exceeding tall structures

TIAN Shuming1,3, ZHENG Xuanpeng2

(1 Department of Design, Research & Development, Tahoe Group, Beijing 100022, China;2 John A. Martin & Associates (Beijing) Co. , Ltd. , Beijing 100020, China;3 Fujian Wanboyu Construction Technology Development Co. , Ltd. , Xiamen 361009, China)

Abstract: Nominal composite stress controlling method and criteria of concrete or composite small eccentric tension frame column in code-exceeding tall structures were discussed in terms of interface performance between rebar ( steel ) and concrete, check method of recoverability under moderate earthquake, shear calculation mode, possible failure modes, member ductility, section design, etc. The results show that demand of steel for interface bond is below rebar, steel will be active earlier to decrease the nominal stress of concrete; nominal tensile stress limit value calculated by the method of Technical specification for concrete structures of tall building( JGJ 3—2010) is corresponding with the physical state that the concrete is fully cracked and out of work, which belongs to the verification category of serviceability limit state; the suggested nominal composite stress method by this paper is suitable for recoverability check under moderate earthquake or occasionally occurred wind load, nominal tensile stress controlling method and nominal shear stress controlling method are particular cases of this method, the limit values of nominal tensile stress and nominal shear stress can be taken as 2. 5f tk and 0. 5 f tk respectively under non-seismic design cases, and 2ftkand 0. 4ftkrespectively under seismic design cases, nominaltensile stress controlling method is preferred when shear force is smaller; the failure mode that longitudinal rebar is sheared directly should be considered when nominal tensile stress reaches the above values, the composite stress of rebar or steel should be calculated when nominal tensile stress exceeds the above values, which belongs to ultimate limit state and need check the stability. Lastly, an actual engineering was applied to confirm the feasibility of the suggested method and limit values by this paper.

Keywords:concrete frame column; composite frame column; small eccentric tension; nominal tensile stress; nominal shear stress; nominal composite stress