This paper experimentally investigated the flexural behavior of reinforced recycled aggregate concrete(RAC)beams reinforced with glass fiber-reinforced polymer(GFRP)bars.A total of twelve beams were built and tested u...This paper experimentally investigated the flexural behavior of reinforced recycled aggregate concrete(RAC)beams reinforced with glass fiber-reinforced polymer(GFRP)bars.A total of twelve beams were built and tested up to failure under four-point bending.The main parameters were reinforcement ratio(0.38%,0.60%,and 1.17%),recycled aggregate replacement ratio(R=0,50%,and 100%)and longitudinal reinforcement types(GFRP and steel).The flexural capacity,failure modes,flexibility deformation,reinforcement strains and crack distribution of the tested beams were investigated and compared with the calculation models of American code ACI 440.1-R-15,Canadian code CSA S806-12 and ISIS-M03-07.The tested results indicated that the reinforcement ratio has great influence on the ultimate load,crack width and deflection of GFRP-RAC beams,the recycled aggregate replacement ratio has little influence on it.However,it was found that the reinforcement ratio has no obvious influence on the cracking load which was only related to the recycled aggregate replacement ratio.The average cracking load decreased by 5%and 15%as the recycled aggregate replacement ratio increased from 0 to 50%and 100%.For the steel-RAC beams,the ultimate load was found to be about 1/2 of the ultimate load of GFRP-RAC beam under the same condition and the trend of strain,deflection and crack width were different from GFRP-RAC beams.This is due to the different material properties of GFRP bars and steel rebar.On the other hand,the calculation results showed that ACI 440.1-R-15 and CSA S806-12 underestimated the ultimate load of GFRP-RAC beams.Moreover,the deflection prediction of GFRP-RAC beams by CSA S806-12 is relatively accurate compared with ACI 440.1-R-15 and ISIS-M03-07.As for the prediction of crack width,the results of ACI 440.1-R-15 prediction were in good agreement with the experimental results at the ultimate load,with the average value of 1.09±0.28.展开更多
A variety of new materials in the field of concrete technology have been developed during the past three decades with the ongoing demand of construction industry to meet the functional, strength, economical and durabi...A variety of new materials in the field of concrete technology have been developed during the past three decades with the ongoing demand of construction industry to meet the functional, strength, economical and durability requirements. Though reinforced concrete has high strength and is most widely used construction material it suffers from disadvantages like corrosion of steel, susceptibility to chemical and environmental attack. In order to overcome the above deficiencies of reinforced concrete new materials （special concrete composites） have been developed over the past three decades. Glass Fibre Reinforced Polymer （GFRP） is one such material with wide range of applications. Based on the preliminary investigations on GFRP bars, an optimum fiber/resin ratio of 7：3 was arrived. The tensile strength of GFRP bars is comparable to that of the mild steel as per the tests carried out, but the modulus of elasticity is about 25-30 percentage of that of steel bars. This paper deals with the experimental investigations carried out on small slab panels supported on all four edges with effective spans of 0.9 m ~ 0.45 m, which is a part of large research problem undertaken with different ratios of 10ng span to short span with different support conditions. The test results are compared with similar slab panels reinforced with conventional mild steel bars.展开更多
基金The authors gratefully acknowledge the support of the National Natural Science Foundation of China(51704029)Liaoning Revitalization Talents Program(XLYC1807044,XLYC1807050).
文摘This paper experimentally investigated the flexural behavior of reinforced recycled aggregate concrete(RAC)beams reinforced with glass fiber-reinforced polymer(GFRP)bars.A total of twelve beams were built and tested up to failure under four-point bending.The main parameters were reinforcement ratio(0.38%,0.60%,and 1.17%),recycled aggregate replacement ratio(R=0,50%,and 100%)and longitudinal reinforcement types(GFRP and steel).The flexural capacity,failure modes,flexibility deformation,reinforcement strains and crack distribution of the tested beams were investigated and compared with the calculation models of American code ACI 440.1-R-15,Canadian code CSA S806-12 and ISIS-M03-07.The tested results indicated that the reinforcement ratio has great influence on the ultimate load,crack width and deflection of GFRP-RAC beams,the recycled aggregate replacement ratio has little influence on it.However,it was found that the reinforcement ratio has no obvious influence on the cracking load which was only related to the recycled aggregate replacement ratio.The average cracking load decreased by 5%and 15%as the recycled aggregate replacement ratio increased from 0 to 50%and 100%.For the steel-RAC beams,the ultimate load was found to be about 1/2 of the ultimate load of GFRP-RAC beam under the same condition and the trend of strain,deflection and crack width were different from GFRP-RAC beams.This is due to the different material properties of GFRP bars and steel rebar.On the other hand,the calculation results showed that ACI 440.1-R-15 and CSA S806-12 underestimated the ultimate load of GFRP-RAC beams.Moreover,the deflection prediction of GFRP-RAC beams by CSA S806-12 is relatively accurate compared with ACI 440.1-R-15 and ISIS-M03-07.As for the prediction of crack width,the results of ACI 440.1-R-15 prediction were in good agreement with the experimental results at the ultimate load,with the average value of 1.09±0.28.
文摘A variety of new materials in the field of concrete technology have been developed during the past three decades with the ongoing demand of construction industry to meet the functional, strength, economical and durability requirements. Though reinforced concrete has high strength and is most widely used construction material it suffers from disadvantages like corrosion of steel, susceptibility to chemical and environmental attack. In order to overcome the above deficiencies of reinforced concrete new materials （special concrete composites） have been developed over the past three decades. Glass Fibre Reinforced Polymer （GFRP） is one such material with wide range of applications. Based on the preliminary investigations on GFRP bars, an optimum fiber/resin ratio of 7：3 was arrived. The tensile strength of GFRP bars is comparable to that of the mild steel as per the tests carried out, but the modulus of elasticity is about 25-30 percentage of that of steel bars. This paper deals with the experimental investigations carried out on small slab panels supported on all four edges with effective spans of 0.9 m ~ 0.45 m, which is a part of large research problem undertaken with different ratios of 10ng span to short span with different support conditions. The test results are compared with similar slab panels reinforced with conventional mild steel bars.
