开展了19根素混凝土柱极限承载力试验,提出了素混凝土柱长细比和偏心率的合理取值范围,采用非线性有限元方法对试验柱承载力进行计算,通过理论分析和试验数据回归,提出了素混凝土柱极限承载力计算方法。计算结果表明:当试验柱长细比大于15与偏心率为0.3时,素混凝土柱的破坏模式为截面受拉破坏,未能充分发挥混凝土以受压为主的材料性能;当试验柱长细比不大于15与偏心率不大于0.3时,其破坏模式为截面受压破坏。承载力有限元算法计算值与试验值的平均比值为0.995,方差为0.0018,计算值与试验值吻合较好,有限元算法可用于素混凝土柱的参数分析。提出的素混凝土柱极限承载力计算方法考虑了长细比和偏心率对承载力影响的耦合作用,其计算值与有限元算法计算值的平均比值为0.976,方差为0.003,表明提出的算法具有较高的精度,且偏安全。
The tests of ultimate bearing capacity for 19 plain concrete columns were carried out. The reasonable scopes of slenderness and eccentricity of plain concrete columns were proposed. The bearing capacities of test columns were calculated by nonlinear finite element method.A calculation method of ultimate bearing capacity for plain concrete column was presented by theoretical analysis and regression of test data. Calculation result shows that when the slendernesses of test columns are higher than 15 and the eccentricities are 0.3,their failure modes are section tensile failure,which can not play full material performance of compression.When the slendernesses are not higher than 15 and the eccentricities are not higher than 0.3,their failure modes are section compression failure.The mean ratio of calculated values by the finite element method to test values is 0.995,the variance is 0.001 8,so the calculated value fits well with test value,and the finite element method can be used for the parameter analysis of plain concrete column.Based on considering the coupling influence of slenderness and eccentricity on bearing capacity,in the proposed calculation method of ultimate bearing capacity,the mean ratio of calculated values by the proposed method and the finite element method is 0.976,the variance is 0.003,which indicates that the proposed method has high precision and high safety.2 tabs, 17 figs,20 refs.