玻璃纤维增强套管钢筋混凝土组合柱偏压承载力计算

对9根不同长细比和6根不同偏心距的玻璃纤维增强(GFRP)套管钢筋混凝土组合柱进行试验研究。试验结果显示:偏心距和长细比对GFRP套管钢筋混凝土组合柱的力学性能有很大的影响。随着偏心距的增大,试件的破坏形态逐渐由压缩破坏向拉伸破坏转变;随长细比的增大,试件的破坏形态则由材料破坏向失稳破坏过渡。试件的极限承载力亦随偏心距和长细比的增大而降低,但降低的幅度变缓。在试验的基础上,对试验数据进行统计回归,得到GFRP套管钢筋混凝土组合柱的长细比折减系数和偏心距折减系数,进而得到轴压组合长柱及偏压柱的承载力计算公式。按建议的组合柱承载力计算公式计算的结果与前人文献中的试验结果吻合较好,说明本文建议的组合柱承载力公式有一定的实际意义。

CALCULATION OF BEARING CAPACITY OF ECCENTRICALLY LOADED CONCRETE-FILLED GFRP TUBULAR LONG COLUMNS

A total of 15 concrete-filled glass fiber reinforced polymer(GFRP) tubular columns were tested and the specimens were divided into two groups.One group consisted of 6 specimens considering the eccentricity changes,the other consisted of 9 specimens considering the slenderness ratio changes.The test results showed that the eccentricity and slenderness ratio had great influence on mechanical properties of the concrete-filled GFRP tubular columns.With the increase of eccentricity,the destruction configuration of test specimens took place transformation from compression to tension failure gradually,and with the increasing of the slenderness ratio,the failure form of specimens changed from material damage to the instability destruction.The ultimate bearing capacity also decreased with the increasing of the eccentricity and slenderness ratio,but the amplitude of reducing slowed down.Based on the test data statistical regression,the reduction coefficient of the slenderness ratio and eccentricity of composite columns was obtained,and then the bearing capacity calculation formula of the axis pressure long columns and the eccentric-loaded columns was derived.The calculated results were compared with the experimental results,which showed a good agreement.These indicated that the proposed bearing capacity formula of the composite columns had a certain practical significance.