通过18根CFRP钢管混凝土轴压柱和用于对比的6根钢管混凝土轴压柱的承载力试验研究,初步探讨CFRP钢管混凝土轴压柱的受力性能以及CFRP对钢管混凝土轴压柱承载力的提高效果。分析了CFRP约束效应系数和长细比对CFRP钢管混凝土轴压柱承载力的影响。研究结果表明:在本次试验的参数范围内,CFRP可以有效提高钢管混凝土轴压柱的承载力;CFRP对钢管混凝土轴压柱承载力的抬高率近似随着CFRP约束效应系数的增加而增加、随着长细比的增加而减小,当长细比达到某一定值时,提高率为零。并根据试验所得到的长细比影响折减系数引入钢管混凝土的长细比影响折减系数,确定了CFRP钢管混凝土轴压柱承载力的计算方法,与试验结果比较吻合良好。
This paper presents an experimental work for concrete filled CFRP steel tubes subjected to concentrically axial compression. The mechanical properties and the increment ratio of load bearing capacity of the concentrically compressed concrete filled steel tube columns due to CFRP are studied. The test specimens include 16 concentrically compressed concrete filled CFRP-steel tube columns and 8 concrete tube columns without CFRP. Influences of the CFRP confinement index and the slenderness radio on the load bearing capacity of the concentrically compressed concrete filled CFRP-steel tube columns are analyzed. It is found: within the scope of the test, CFRP would enhance the load bearing capacity of the concentrically compressed concrete filled tube columns effectively; the increment ratio of load bearing capacity due to CFRP increases with the increment of CFRP tube confinement index and decreases with the increment of slenderness ratio. A slenderness ratio index is also presented, capable of predicting the axial load strength of concrete filled CFRP steel tube members. Experimental results are in good agreement with the predicted values.