【摘要】 采用喷射短切玻璃纤维增强聚合物(GFRP)的方法对砖砌体受压标准试件进行抗压加固,通过对砖砌体轴心受压试件和偏心受压试件的抗压加载试验,探讨了该加固方法对砖砌体受压破坏形态、极限承载力和极限变形能力的影响,并研究了喷射加固层厚度、短切玻璃纤维长度以及加铺玻璃纤维粗网格布对砌体受压加固效果的影响.结果表明:喷射GFRP加固方法可以极大地提高砖砌体的极限受压承载力和变形能力,有效延缓砌体受压构件初始裂缝的出现和扩展,改善无筋砌体受压的脆性破坏特征;轴压加固试件的极限受压承载力和极限压应变分别平均提高79.9%和60.3%,偏心受压试件的极限受压承载力和极限压应变分别平均提高136.7%和90.8%;砌体受压加固的最佳喷射厚度为7mm,最佳短切纤维长度为25mm.文中还提出了喷射GFRP抗压加固矩形截面砌体柱的极限承载力简化计算公式,计算结果与试验结果吻合良好.更多还原

【Abstract】 In this paper,firstly,standard compressive specimens of brick masonry were strengthened with sprayed chopped glass fibre-reinforced polymer(GFRP).Then,the specimens were tested under both the concentrically and the eccentrically axial compressions,and the failure mode,the ultimate bearing capacity and the ultimate deformability of the strengthened specimens were explored.Finally,the strengthening effects affected by the spraying thickness,the chopped fibre length and the combination with glass fibre gridding sheet were investigated.The results indicate that(1) spraying GFRP significantly increases the ultimate bearing capacity and the deformability of brick masonry in compression,effectively postpones the emergence and propagation of initial cracks,and fairly improves the brittle behaviour of unreinforced masonry;(2) the ultimate compressive capacity and the ultimate compressive strain of the strengthened specimens under concentric compression averagely increase by 79.9% and 60.3%,respectively,while those of the specimens under eccentric compression averagely increase by 136.7% and 90.8%,respectively;and(3) the optimal spraying thickness and chooped fibre length for compressively-streng-thened brick masonry are 7mm and 25mm,respectively.In addition,the calculated values of ultimate bearing capacity obtained by the proposed simplified formula accord well with the test ones.更多还原