Experimental Study On Axial Compression Behavior Of Concrete Column With Recycled Clay Brick Aggregate

With the rapid development of urbanization in our country,quite a number of building materials need to be replacement and considerable amount of buildings need to be demolished due to damages caused by artificial and natural factors.During this period,a lot of wasted clay bricks are produced,which become construction waste.Therefore,the disposal and utilization of these wasted clay bricks become an urgent problem in the building construction industry.In this paper,the wasted clay bricks are reused to partly replace natural coarse aggregate in the production of concrete and concrete column,then the properties of concrete and concrete column are studied.The physical properties of coarse aggregate are tested,which is made by the crushing and screening of clay bricks.Concrete specimens with clay brick recycled aggregate replacement rate of 0%,10%,20%,30%,40%,50% are prepared,of which the compression strength test is conducted.According to the analysis of the experiment results,concrete columns with clay brick recycled aggregates replacement rate of 0%,20%,25%,30%,35% are produced,of which the axial compression strength test is conducted.Through the analysis of physical properties of clay brick recycled aggregates and analysis of compression strength tests of concrete specimens and concrete columns under different aggregate replacement rates,conclusion are drawn as follows:1)There are differences in density,water absorption,crushed value between clay brick recycled aggregate and natural aggregate.From the point of requirement values of aggregate,the clay brick recycled aggregate is feasible for the preparation of concrete.2)The clay brick recycled aggregate concrete compressive specimen has similar damage forms with that of natural aggregate concrete.With the admixture amount increasing of clay brick recycled aggregate,the compression strength of concrete become lower.This results has great relationship with properties of recycled aggregate,water absorption of it,skeleton effect of natural aggregate and workability of it.Taken safety and economy factors into consideration,the compressive strength of clay brick recycled aggregate concrete can be calculated in accordance with the natural aggregate concrete when the replacement rate is lower than 30%,but a reduction factor need to multiply for the compressive strengthcalculation.3)The bearing process of recycled aggregate concrete column also contains the elastic stage,the plastic stage and failure stage.Under the same loading condition,the larger admixture amount of recycled aggregate the concrete has,the bigger its axial displacement is;the smaller failure load and larger axial displacement show that recycled aggregate improves the plasticity of concrete column.The design value of compression bearing capacity of recycled aggregate concrete column normal section can refer to code for design of concrete structures and the value should be multiplied by a corresponding reduction factor.4)Through the comprehensive beneficial analysis of clay brick recycled aggregate concrete,we come to the conclusion that it has certain economic benefits,environmental benefits and social benefits;so the clay brick recycled aggregate concrete has certain application prospect.