对称配筋偏心受压钢筋混凝土柱N_u-M_u曲线特性及数值分析

周清¹，国伟¹，齐麟²

1.滨州市规划设计研究院有限公司，山东 滨州  256600；2.中国民航大学交通科学与工程学院，天津  300300

摘要：为分析截面面积、配筋率、钢筋强度、混凝土强度等参数对对称配筋偏心受压钢筋混凝土（reinforced concrete，RC）柱的极限弯矩M_u与极限轴力N_u（N_u-M_u）曲线的影响，推导对称配筋偏心受压RC柱的M_u与N_u的函数关系式并绘制N_u-M_u曲线。采用软件ANSYS对RC柱进行数值分析，分析柱底截面的最大极限弯矩与最大极限轴力数值分析结果与理论计算结果的相对差。研究表明：极限轴力随截面面积、配筋率、钢筋强度、混凝土强度的增大而增大，截面面积对其影响最大，混凝土强度、配筋率对其影响较小，钢筋强度对其影响最小；最大极限轴力、最大极限弯矩的理论计算结果均大于数值分析结果；最大极限弯矩的理论计算结果与数值分析结果的相对差大于最大极限轴力，前者约为10%，后者约为5%。

关键词：偏心受压RC柱；对称配筋；N_u-M_u曲线；参数分析；数值分析

The characteristics of N_u-M_u curve and numerical analysis of eccentrically loaded RC columns with symmetric reinforcement

ZHOU Qing¹, GUO Wei¹, QI Lin²

1.Binzhou Planning & Design Research Institute Co., Ltd., Binzhou 256600, China;

2.College of Transportation Science and Engineering, Civil Aviation University of China, Tianjin 300300, China

Abstract: To analyze the influence of parameters such as cross-sectional area, reinforcement ratio, steel bar strength, and concrete strength etc., the relationship between the ultimate bending momentM_uand the ultimate axial forceN_u(N_u-M_u) curve of eccentrically loaded reinforced concrete (RC) columns with symmetrical reinforcement, the functional relationship between M_u and N_u for symmetrically reinforced eccentrically loaded RC columns is derived and the N_u-M_u curve is plotted. Software ANSYS for numerical analysis of RC columns is used to analyze the errors between the numerical analysis results of the maximum ultimate bending moment and the maximum ultimate axial force of the column base section and the theoretical calculation results. The study finds that the ultimate axial force increases with the increase of cross-sectional area, reinforcement ratio, rebar strength, and concrete strength, with the cross-sectional area having the greatest influence, concrete strength and reinforcement ratio having a smaller influence, and steel bar strength having the smallest influence; the theoretical calculation results of the maximum ultimate axial force and maximum ultimate bending moment are both greater than the numerical analysis results; the error between the theoretical calculation results and the numerical analysis results of the maximum ultimate bending moment is bigger than that of maximum axial force, the former is approximately 10%, while the latter is approximately 5%.

Keywords: eccentrically loaded RC column; symmetric reinforcement; N_u-M_ucurve; parameter analysis; numerical analysis