玻璃纤维复材筋与混杂纤维混凝土黏结性能研究

RESEARCH ON BOND BEHAVIOR BETWEEN GFRP BARS AND HYBRID FIBER REINFORCED CONCRETE

通过对24个混杂纤维混凝土试件的拉拔试验,研究玻璃纤维复材(GFRP)筋与混杂纤维混凝土的黏结性能,分析钢纤维和聚乙烯醇(PVA)纤维的体积率对黏结性能的影响。研究表明:钢-PVA纤维混凝土与GFRP筋的黏结滑移曲线可以分为上升段、下降段和残余段,在残余段内黏结强度呈往复上升下降的衰减过程,峰值每次下降40%～50%。总纤维体积率为0. 9%时,随着钢纤维体积率占比增大,GFRP筋与混杂纤维混凝土之间的黏结性能逐渐提高,且拉拔过程中耗能逐步增加。最后,根据试验得到的黏结滑移曲线进行拟合,提出黏结滑移的本构关系。

By the pullout tests of 24 hybrid fibers reinforced concrete specimens, the bond behavior between glass fiber reinforced polymer ( GFRP ) bars and different fibers volume fraction of hybrid fibers reinforced concrete was discussed.The results showed that the bond-slip curve of steel-PVA fiber concrete and GFRP bars could be divided into ascending, descending and residual sections. In the residual section, the bond strength decreased with a reciprocating rise and fall, and the peak value decreased by 40% to 50% each time. When the total fiber volume ratio was 0. 9%, the bond performance between GFRP bars and concrete and the energy consumption gradually increased during the drawing process. Finally, the corresponding GFRP bars and concrete bond-slip curve were fitted out and the bond-slip constitutive relation was proposed according to the result of the test.