【摘要】 确定截面受压区对应圆心角2απ是钢筋混凝土圆柱正截面受弯承载力计算的关键问题。运用数值计算方法对α变化规律进行研究,结果表明轴压比和纵筋配筋特征值是影响α的两个主要因素。α随轴压比增加呈线性增加,同时纵筋配筋特征值对α和轴压比的线性关系也有显著影响。根据数值计算的结果进行回归,提出了用轴压比和纵筋配筋特征值直接表达的α计算公式,计算结果和数值计算结果吻合很好。在此基础上根据规范公式对正截面受弯承载力进行计算,数值计算结果和试验结果比较发现,在低轴压下规范公式计算结果偏于不安全。建议了正截面受弯承载力计算的新方法,计算结果精度较高,并且克服了规范公式在低轴压下偏于不安全的不足。更多还原

【Abstract】 The determination of the central angle,2απ,corresponding to compression zone is the key problem to calculate the flexural capacity of normal section of reinforced concrete circular columns.Numerical analysis was carried out to analyze the rule of α.The results show that the axial compression ratio and longitudinal reinforcement eigenvalue are the two main parameters which significantly influence α.The numerical analysis results show that α increases linearly with the increase of axial compression ratio,and longitudinal reinforcement eigenvalue can influence this linear relationship.Based on the regression of the numerical analysis results,the computing formula of α is established,in which axial compression ratio and longitudinal reinforcement eigenvalue are the only two parameters.It is found that the calculated flexural capacity from formula provided in the code is significantly larger than the numerical results and test results when the axial compression ratio is low.In order to overcome this deficiency,a new method is proposed to calculate flexural capacity,and the calculated results agree well with the numerical results.更多还原