Research On Technical Performance Of Cement Stabilized Construction Waste Pavement Base

The demolition of buildings will generate a large amount of construction waste.Construction waste is usually treated by on-site open-air stacking and landfill landfill disposal.This treatment not only occupies a large amount of land,but also pollutes the soil,waters and air,has a certain impact on people's lives.At the same time,as the construction industry continues to develop,need to consume a lot of natural stone materials,resulting in a shortage of natural stone resources,how to recycle construction waste has become a research hotspot.It is of great significance to research on the application of construction waste recycled aggregate instead of natural gravel aggregate in roads.This paper focuses on the technical performance of construction waste applied to the pavement base.The paper processing sorting the construction waste into brick aggregate and concrete aggregate by certain methods and mechanical equipment,the technical properties of the two aggregates were analyzed.Cement stabilized concrete aggregate with different mix ratios(6 kinds of concrete aggregate content and 4 kinds of cement dosage)were prepared,through the compaction test and the 7d compressive strength test,the effects of concrete aggregate content and cement dosage on compaction characteristics and compressive strength were analyzed,and the concrete aggregate content and cement dosage applicable to the pavement base were recommended.Experimental research on the effect of concrete aggregate content on the strength(compressive strength,splitting strength,flexural strength),modulus(modulus of compression resilience and modulus of elasticity),shrinkage performance(dry shrinkage performance and temperature shrinkage performance)and durability(freezing resistance,water stability,dry-wet cycle characteristics and anti-scour performance)of the mixture,as well as the effect of snow melting agent on freezing resistance,water stability and dry-wet cycle characteristics of the mixture.The research shows that construction waste should be processed and sorted into brick aggregate and concrete aggregate,brick aggregate can be used for subgrade filling,concrete aggregate can be used for pavement base and subbase;as the concrete aggregate content increases,the maximum dry density of the mixture decreases,and the optimum moisture content increases;When using 100% concrete aggregate and 5% cement dosage,the strength of the mixture meets the strength requirements of the pavement base of the extremely heavy and heavy traffic grade pavement of highways and first-class highways.With the increase of concrete aggregate content,the compressive strength,compressive modulus and modulus of elasticity of the mixture increases first and then decreases lightly,and the splitting strength and flexural strength increase gradually;The increase of concrete aggregate content,has little effect on freezing resistance,water stability and dry-wet cycle characteristics of the mixture,but has a great influence on the shrinkage performance and anti-scour performance of the mixture,it should be fully considered in the design of pavement structure;The snow melting agent will impair the freezing resistance of the mixture,care should be taken to prevent the snow melting agent from penetrating into the pavement base.