考虑P-δ效应的钢筋混凝土框架柱设计方法  

Design methods of reinforced concrete frame column considering P-δ effect

作　　者：魏巍[1] 朱爱萍[2] 刘毅[1] 白绍良[1] 

机构地区：[1]重庆大学,重庆400045 [2]中国建筑科学研究院,北京100013

出　　处：《建筑结构学报》2006年第5期64-71,共8页Journal of Building Structures

基　　金：国家自然科学基金资助项目(59678035)

摘　　要：针对工程界对《混凝土结构设计规范》(GB 50010—2002)及《高层建筑混凝土结构技术规程》(JGJ 3—2002)考虑二阶效应的设计方法中是否已充分考虑了单柱P-δ效应的疑虑,通过有限元分析算例,对框架结构在P-δ效应作用下一阶弯矩的影响规律进行了详细说明。在指出美国规范ACI Committee 318和欧洲规范Eurocode 2对考虑P-δ效应的柱等效长度取值不尽合理以及考虑框架柱端不等偏心距影响的折减系数Cm取值过于粗略后,利用框架的有限元分析结果提出了等效长度的定义和设计取值方案,并结合试验结果和分析给出了更为合理的Cm系数取值建议。本文的建议为进一步完善考虑二阶效应的框架柱设计方法提供了参考。Motivated by the doubt whether P-δ effect of a single column is considered thoroughly in the design procedure of second-order analysis, such as the ＂Code for design of reinforced structures（GB 50010---2002）＂ and ＂Technical specification for concrete structures of tall building （JGJ 3--2002）＂, this paper presents a detailed illustration of the rules of first-order moment of frames influenced by P-δ effect based on a series of FEM analysis. The inappropriate determination of P-δ effect, equivalent length and reduction factor Cm considering the influence of column end moment asymmetric eccentricity in frames according to ACI 318 and Eurocode 2 are pointed out. Consequently, a better definition and a more reasonable value of the equivalent length are proposed based on FEM analysis, an improved value of reduction factor Ca is also proposed on the basis of experimental results. This paper attempts to provide a reference for refined design methods of frame column considering second order effect.

关 键 词：钢筋混凝土 二阶效应 P-Δ效应 等效长度 

分 类 号：TU375.4[建筑科学—结构工程]