Recycle Aggregate Concrete Mixture Proportion Method Design And Experimental Study Of Mechanical Property Based On Pulp Content

The residual mortar is the main factor that influence the properties of RCA andRAC,But it has not been received enough attention in traditional recycled aggregateconcrete mix proportion design.In this paper, combining the idea of EMV and the mixtureproportion method based on free water cement ratio, we propose a new mixture proportionmethod of recycled aggregate concrete－Recycled aggregate concrete mixture proportionmethod based on pulp content.This method aimed to reduce residual mortar influence onthe properties of recycled aggregate concrete.The main content of this paper is as follows:(1)Pulp content shows the content of residual mortar on recycled coarse aggregatesurface.Firstly, this paper demonstrated the important relationship between pulp contentand basic properties of recycled coarse aggregate through experiment,has been clear aboutthe necessity of proposing the mixture proportion method based on pulp content.Secondly,comparing with different mixing proportion method by recycled aggregateconcrete working performance and mechanical properties through the testresults.Thirdly,analysis of the effect of pulp content to the properties of recycled aggregateconcrete.The results show that:The test mixture proportion method can improve recycledaggregate concrete cube compressive strength, splitting tensile strength,flexuralstrength.And recycled aggregate concrete compressive strength, splitting tensile strength,flexural strength decreases with the increase of pulp content.(2)The test research mix proportion with36different recycled coarse or fineaggregate content of recycled aggregate concrete.It test the working performance andmechanical properties of recycled aggregate concrete, and orthogonal analyze testresults.The test shows:It got the relationship between coarse or fine aggregate content andrecycled aggregate concrete various properties.Also it got the optimum content of recycledcoarse and fine aggregate under mixture proportion method based on pulp content.At lastthe paper obtained the relationship formula through between the recycled concretesplitting tensile strength and compressive strength through statistical regression analysis oftest data.(3)Using Recycled aggregate concrete mixture proportion method based on pulp content, the test compounded premixed recycled aggregate concrete of four strength grade,and tested its mechanical properties.The recycled concrete’s mechanics performanceindexes are greater than ordinary concrete with same water/cement ratio,so the papersuggests that increase water/cement ratio to get the premixed recycled concrete of samestrength grade.