Experimental Research On Stressing Performances Of Recycled Concrete Simply-supported Beams

How to dispose more and more scrap concrete is a hot potato and need settle urgently for the government of each country.Through failing to pieces,classification and mixing according to certain proportion,the scrap concrete would form recycled concrete aggregate.Using propotion or full recycled concrete aggregate as aggregate concrete to structural engineering,tests and theory studies,such as experimental research on behavior of recycled concrete frame,are obligatory.The paper studies flexural and shear behaviors of recycled concrete beams by test.The intent of this paper is to investigate the flexural behavior of 4 recycled concrete simply-supported beams with same percenttage of reinforcement and axial compressive strength but different replacement ratio of recycled aggregate.Besides the flexural capacity of normal section,the characteristics of both deflection and cracking are analyzed.Based on the experimental results,the following conclusions are drawn.In bending,the recycled concrete beam also has elastic,cracking,yield and ultimate point.The average strain measured on cross-section obliges to the plane section assumption.Under same conditions,the cracking and ultimate moment of recycled concrete beam are similar to conventional concrete beam.At the end of the paper,after verifying the formula suggested by present code for Design of Concrete Structures(GB50010-2002)for recycled concrete beams, a conclusion can be drawn that the ultimate moment of recycled concrete beam can be estimated by the formula suggested by present code,whereas the cracking moment,the deflection and the width of crack can not.The intent of this paper is to investigate the shear behavior of 4 recycled concrete simply-supported beams with same percenttage of reinforcement and axial compressive strength but different replacement ratio of recycled aggregate.The characteristics of both shear capacity of oblique section and diagonal cracking are analyzed.Based on the experimental results,the following conclusions are drawn that the shear capacity of recycled concrete beam reduces with is similar to the natural aggregate concrete beam.Finally,a formular related to the shear capacity of recycled concrete beams is proposed and recommeded.Finally, the bending regidity formula is studyed.The coefficient of formula is corrected.