【摘要】 外包角钢与碳纤维布(CFRP)复合加固钢筋混凝土柱是一种新型加固方式。对6根复合加固柱及1根未加固对比柱进行低周反复受剪性能试验研究,探讨影响复合加固柱抗剪性能的因素,并分析不同条件下CFRP与外包钢缀板的应变情况。试验结果表明,复合加固方法能显著提高钢筋混凝土柱的抗剪承载力,试验中最大提高47%,且复合加固柱在破坏时延性得到较大程度的改善。在轴压比较低的范围内,复合加固柱的抗剪承载力随轴压比的增大而增大,但其延性下降。随着钢缀板加固量的增大,复合加固柱的抗剪承载力随之增大。随着复合加固柱剪跨比的增大,其抗剪承载力随之降低,但外加片材应变增大。CFRP与角钢复合加固体系能很好的约束混凝土的横向变形,两种材料能良好地共同工作,但约束材料强度的发挥是有限的,在达到极限承载力时,两种加固材料都不能被充分利用。更多还原

【Abstract】 The objective is to develop an innovative strengthening system for concrete columns by using a combination of externally bonded carbon fiber reinforced polymer(CFRP)sheets and externally bonded steel angles.Experiments were carried out for a non-strengthened control column and six columns strengthened with a combination of bonded CFRP and bonded steel angles,and the strengthening effect on the shear performance were investigated under axial load and cyclic shear load.Factors that affect the shear behavior of the strengthened columns as well as the strains of CFRP and the bonded steel pieces under various conditions were discussed.Experimental results reveal that strengthened columns exhibit higher shear capacity and superior ductility in comparison with the control column,with the shear capacity being increased by up to 47%.At relatively low axial load ratio,shear capacities of the strengthened columns increase with the increase of axial load ratio.With the increase of shear-span ratio,shear capacities decrease,whereas the strains of the bonded materials increase significantly.The combination strengthening system can effectively restrain the transverse deformation of concrete columns,and both CFRP and steel angles can work well with the concrete.However,the restraint effect of the combination strengthening system is limited,neither CFRP nor steel angles can make the best of its strength at ultimate shear capacity state.更多还原