钢筋与FRP筋混杂配筋混凝土梁的抗弯性能

Flexural performance of hybrid steel and FRP reinforced concrete beams

为了在试验基础上研究钢筋与纤维增强复合材料(fibre reinforced plastic,FRP)筋混杂配筋梁的抗弯性能,运用有限元软件ABAQUS对已有混杂FRP筋试验梁进行建模和非线性分析,研究了FRP筋种类、混凝土强度、等效配筋率等因素的影响.基于有限元结果拟合出了适筋破坏时混杂FRP筋梁的FRP筋应力表达式和承载力计算公式,并运用已有试验数据验证其正确性.结果表明:等效配筋率对混杂FRP筋梁的承载能力和变形性能影响最为显著,其次为FRP筋种类;混凝土强度对承载力有一定的影响,但对刚度影响较为有限;FRP筋应力表达式能较准确计算混杂FRP筋梁抗弯承载力.

To conduct an experimental study of the flexural theory of hybrid steel and fibre reinforced plastic(FRP)reinforced beams,the finite element software ABAQUS was used to model and nonlinearly analyse existing hybrid FRP/steel reinforced test beams.The effects of FRP bar type,concrete strength,and the equivalent reinforcement ratio on the bending performance of hybrid FRP/steel reinforced beams were then studied.Finite element results revealed that the stress expression of FRP bars could be obtained and a formula for the bearing capacity of hybrid FRP reinforced beams could be derived.Finally,experimental data were used to verify the correctness of the formula.Results showed that the equivalent reinforcement ratio had the most significant effect on the bearing capacity and deformation performance of hybrid FRP bars beams,followed by FRP bar type.The strength of concrete had a certain effect on the bearing capacity but had little effect on stiffness.Based on the stress expression of FRP bars in this study,the flexural capacity of hybrid FRP reinforced beams were accurately calculated.