纤维增强聚合物条带约束混凝土圆柱的耐久性

通过碳化、盐溶液干湿循环下碳纤维增强聚合物布(CFRP)和玻璃纤维布(GFRP)条带约束混凝土圆柱耐久性试验,对比分析了环境作用、纤维布类型、粘着剂类型(胶Ⅰ和胶Ⅱ)对混凝土圆柱轴压性能的影响.结果表明,无论是否受环境作用,纤维增强聚合物约束圆柱的轴向应力-应变关系基本呈双线性,其强度与延性都比无约束混凝土圆柱有一定提高.碳化环境对CFRP和GFRP约束圆柱基本没有影响,盐溶液干湿循环作用后FRP条带约束混凝土柱的强度、刚度和延性降低.CFRP约束柱比CFRP约束柱耐干湿循环性能好.此外,胶的种类对耐久性也有一定影响.

Experimental study on durability of concrete cylinders wrapped with fiber reinforced polymer strips

The effect of environment, type of fiber reinforced polymer strips and adhesives on durability of concrete cylinders are studied by comparing the compressive performance of specimens confined with carbon fiber reinforced polymer (CFRP) strip, glass fiber reinforced polymer (GFRP) strip and without strip, which are experienced carbonation test and wet dry cycles of salt solution. The experimental results show that the axial stress strain relationships of the cylinders wrapped with both kinds of FPP strips are basically bilinear, the strength and ductility of wrapped concrete cylinders are higher than those of cylinders without wrapped. Carbonation has no effect on the performance of concrete cylinders wrapped with CFRP and GFRP strips. The strength, stiffness and ductility of FRP strips reinforced concrete cylinders reduced after wet dry cycles in salt solution. The specimens confined with CFRP have higher resistance to wet dry cycles in salt solution than those confined with GFRP. Besides, the type of resin of adhesive to be used may have slightly effect on the resistance.