偏心受拉钢筋混凝土构件截面强度分析研究

根据平截面假定和《混凝土结构设计规范》(GBJ10 89)所规定的基本原则 ,考虑不同的受力情况 ,分别对钢筋混凝土偏心受拉构件正截面强度进行了分析。对按规范公式计算的结果与根据平截面假定计算的结果进行了比较 ,同时还分析了受拉区配筋率和受压区配筋率对钢筋混凝土偏心受拉构件正截面破坏形式和弯矩 -纵向拉力相关曲线的影响。结果表明 :增加受压区配筋率和受拉区配筋率均可增大m -n相关曲线所包围的面积 ,提高钢筋混凝土偏心受拉构件的承载能力。根据受压区配筋率、受拉区配筋率和纵向拉力位置的不同 ,钢筋混凝土偏心受拉构件的破坏形式也不同。对于小偏心和大偏心的适筋破坏形式 ,规范公式精度较好 ,但对超筋破坏形式 ,规范公式误差较大 ,且偏于不安全。

ANALYSIS OF THE SECTION STRENGTH FOR REINFORCED CONCRETE ECCENTRIC TENSION MEMBERS

The section strength for the reinforced concrete eccentric tension members is analyzed based on the traditional “plane sections remain plane” assumption (the Bernoulli′s principle) and the Code of Design of Concrete Structures(GBJ10\|89) respectively.The results calculated by the equations of GBJ10\|89 and equations based on the Bernoulli′s principle are compared.It is also analyzed that steel ratios of tension reinforced and compression reinforced affect the failure mode and the relationship between the moment factor m and tension factor n .The analyzed results indicate that increasing the steel ratio of tension reinforced and compression reinforced can increase the capacity of the reinforced concrete eccentric tension members.The failure modes of the reinforced concrete eccentric tension members are different according to varying the steel ratio of tension reinforced and compression reinforced and the location of tension force.The results calculated by the equations of GBJ10\|89 have good precision for the modes of full tension section and the under\|reinforced section of partial tension section.But the error of results is excessive and on the unsafe side for the failure mode of over\|reinforced section.