Experimental Study On Ratio And Masonry Basic Mechanical Properties Of Recycled Aggregate Concrete Block

With the accelerated process of urbanization in china, there is rapid developmentof the construction industry and which produces a large amount of construction wasteat the same time. These construction waste after processing of recycled aggregateconcrete hollow block is in the line with the six key principles of sustainabledevelopment, with good economic and environmental benefits. However, the recycledaggregate concrete hollow block is a new type of wall materials, we need to set up asound system in order for real application in practical engineering. Based on theproportioning of recycled concrete block and masonry theoretical analysis andexperimental study on basic mechanical properties, this paper provides a theoreticalfoundation and recommended for wide range of regeneration concrete hollow blockin practical engineering applications.This article designed27different proportioning of recycled concrete, whichbased on design concepts of the free cover. Recycled concrete cubs were tested inaccordance with existing norms on compressive strength. Then we analyzed therelationship between aggregate replacement rate, water cement ratio and compressivestrength. In addition, Fitting out the formula of recycled aggregate concrete withcoarse and fine aggregate replacement rate and water cement ratio as parameters. Atlast, concrete mix tables of different strength grade are given.Through the compressive strength test of28concrete hollow block masonryspecimens, the failure modes of masonry, compressive strength, stress-strainrelationship, young’s modulus and Poisson’s ratio were studied. In addition, theimpact on masonry compressive strength of mortar strength and block strength wasalso analyzed. Results show that block strength is the main influencing factors ofcompressive strength of masonry block. When the grade block strength increase alevel, masonry compressive strength will increase55%. However, with the increasingstrength of mortar, masonry compressive strength has increased, but gains are limited.Through the study in experiment, the design values of compressive strength of recycled aggregate concrete hollow block masonry in accordance with values of thecode for design of masonry structures of normal concrete hollow block masonrystrength design values.Through the40recycled concrete hollow block masonry shear test, shear failuremode and shear strength of masonry were studied. Then the factors affecting shearstrength of masonry were analyzed. Results show that the shear performance ofregeneration concrete hollow block masonry is essentially similar to normal concretehollow block masonry. Shear strength of masonry is mainly influenced by mortarstrength. When mortar strength increase a level, the measured shear strength ofmasonry will increase8.7%. Measured value of recycled concrete hollow blockmasonry shear strength along the straight joint formula section is less than thetheoretical value. A fixed formula for the average values of masonry shear strength isgiven.