考虑嵌固支座约束的钢筋混凝土柱数值分析研究

Numerical analysis on reinforced concrete columns with restraint of support

嵌固支座对钢筋混凝土柱根区域具有一定约束作用,而传统纤维单元中并未考虑此约束,对以弯曲破坏为主的钢筋混凝土柱进行数值模拟,发现不考虑嵌固支座约束时柱的承载力较试验值低,且轴压比越大偏低越多.分析混凝土强度和峰值应变对柱正截面抗弯承载力的影响,揭示嵌固支座约束对承载力的提高机理,分别采用修正系数K_(1)、K_(2)、K_(3)反映约束作用对破坏控制截面位置、混凝土强度和峰值应变的影响,建立了修正后的钢筋混凝土柱纤维模型,计算与试验结果吻合良好,表明所提方法有较好的适用性.

The support has a certain constraint effect on the root region of the reinforced concrete column,which is not considered by the traditional fiber element.The numerical simulation of the reinforced concrete column with bending failure is carried out,and it is found that the simulated bearing capacity of the column is lower than the test value,and the larger the axial compression ratio is,the lower it is.It is revealed that the restraint of support improve the bearing capacity by analyzing the influence of concrete strength and peak strain on column flexural bearing capacity of normal section,the parameters K_(1),K_(2),K_(3),are used respectively to reflect the effect of restraint of support on damage control section,the influence of concrete strength and peak strain,the modified fiber reinforced concrete column model is established,the calculation results coincide with the experiment,and shows that the proposed method has better applicability.