角钢-玻璃纤维布复合加固砖柱轴压性能研究

Research on Masonry Columns Strengthened with the Combination of Angle Steel and GFRP Under Axial Load

采用角钢-玻璃纤维布复合加固砖柱,对8根试件(7根加固砖柱和1根未加固砖柱)进行轴心受压试验.将角钢单一加固、玻璃纤维布单一加固及角钢-玻璃纤维布复合加固3种方法分别应用于砖柱加固,对试件的破坏形态、荷载-位移曲线和极限承载力进行研究分析.试验结果表明,不同方法加固砖柱的承载力和延性相比未加固砖柱均有大幅提高,复合加固砖柱将角钢和玻璃纤维布加固的优点有机地结合起来,承载力和延性增大幅度大于单一方法加固砖柱;加固砖柱的承载力随着玻璃纤维布层数的增加而上升,但玻璃纤维布层数增加到一定数量后,加固柱承载力增长不明显;玻璃纤维布对砖柱端角部的约束比中间强,加固柱中有强、弱约束区.在试验的基础上,提出了角钢-玻璃纤维布复合加固砖柱轴压承载力计算方法,计算结果与试验结果吻合良好.

A strengthening technique for masonry columns with the combination of angle steel and GFRP was proposed in this study.Eight specimens(seven strengthened masonry columns and one control column)were tested under axial load.Masonry columns strengthened with angle steel,GFRP and a combination of them were investigated,respectively.The failure modes,load-deformation relationship and bearing capacity of different specimens were analyzed.The test results indicate that the bearing capacity and ductility of strengthened columns increase significantly,and that the composite strengthening scheme combines the advantages of angle steel and GFRP.The bearing capacity of specimens increases with the increase in number of GFRP layers,though the strengthening efficiency decreases when the number reaches a certain extent.In addition,the corner area of masonry columns has stronger confinement than the core area of masonry columns,demonstrating the co-existence of both strong and weak confinement area in specimens.Based on the test results,an analytical model was proposed to calculate the bearing capacity of the composite strengthened masonry columns.The calculating results agree well with the test data.