Research On Performance Of Recycled Aggregate Of Construction Waste For Cement Stabilized Crushed Stone Base

With China’s rapid urbanization,the construction industry has also ushered in a vigorous development opportunity.Construction industry produces a large number of construction waste,which will cause serious environmental pollution.simultaneously,the construction industry and highway construction need a large number of natural stone,and the lack of natural stone resources is increasingly prominent.How to recycle construction waste has become a hot research topic.Cement stabilized gravel base is widely used in asphalt pavement base due to its good performance,and the relevant specifications do not have high requirements for the strength of the pavement base.Therefore,the appropriate graded brick mix recycled aggregate made by removing impurities from construction waste will be used feasibility in cement stabilized macadam base material.In this paper,the recycled aggregate of construction waste is used to replace the natural aggregate for pavement base,and the performance of cement stabilized macadam base mixed with recycled aggregate of construction waste is mainly studied firstly.The paper studies the composition of construction waste and the production process of recycled aggregate,and determines the production process of recycled aggregate;secondly,it studies the properties of recycled aggregate,concrete aggregate and natural aggregate;then it uses six different recycled aggregate content of brick to stabilize the mixture,forming and curing the specimen,and carries out the mechanical properties tests(compressive strength test,splitting strength test)Test),shrinkage test(dry shrinkage test,temperature shrinkage test)and anti-erosion test.The results show that the recycled aggregate has the characteristics of small density,large crushing value and high water absorption;with the increase of the recycled aggregate,the maximum dry density of the mixture decreases,while the optimum moisture content increases;with the increase of the recycled aggregate,the compressive strength of the mixture first increases and then decreases,and the splitting strength gradually increases,all of which meet the specification requirements;the loss of quality owing to anti-erosion test also increases with the increase of recycled aggregate content.When the content is more than 40%,the anti-erosion properties of the mixture decreases significantly.With the increase of recycled aggregate content,the dry shrinkage coefficient and temperature shrinkage coefficient of the mixture will increase,which has a significant impact on the shrinkage of the mixture.In practical engineering,it is necessary to control the amount of recycled aggregate or take some measures to reduce the adverse effect of recycled aggregate on the shrinkage and anti-erosion properties of cement stabilized mixture;The road performance of 5%cement dosage of brick-concrete recycled aggregate cement stabilized crushed stone can meet the relevant specifications of pavement base,and it can be applied to semi-rigid base with considerable economic and social benefits.