Alkalin-Active Red Clay Brick Powder Used As Cementation Materials

Today,as energy conservation and environmental protection become the focus of attention increasingly,the utilization of solid construction waste gains more and more attention at the same time.Solid red brick waste accounted for more than half of the total construction wastes in China,it is typical silicate substance and has chemical activity under the action of active agent,but because of the lack of related research and management measures,there were regarded as useless garbage and were stacked or landfilled casually,caused the waste of resources and the pollution of environment.At this experiments,red clay brick was dried and grounded to be powder(RCBP),RCBP served as major cementation materials under the action of alkalin active to manufacture pastes and mortars,fly ash served as a comparison to RCBP as its similar chemical composition to RCBP so as to evaluate the difference of this two materials.In this experiment,active mineral admixture granulated blast furnace slag(GF)and metakaolin(MT)were added into RCBP in different proportion,NaOH and Na2SiO3 solution used as active agent to active their potential activity.Fluidity,water demand of mix slurry,compressive flexural strength,porosity,microstructure of hardened slurry were tested to determine the optimal composition and dosage of raw materials as well as active and cure condition in the preparation of pastes.On the basis of pastes experiment,mechanism sand and natural sand used as fine aggregate,three different types of mortars were manufactured with a S/B 1/3 to analysis and evaluate the difference among this three mortars so as to evaluate the properties of RCBP-based mortars.Compared to former research other scholars focused on solid red clay brick,this experiment investigates the feasibility of RCBP served as cementation materials,GF and MT were used to improve the defects of low calcium levels,large water demand and low early strength of single RCBP,the alkaline composition in GF had auxiliary active effects on raw materials on the same time.At mortar experiments,0、50%and 100% three different replace rate were used for mechanism sand to replace natural river to manufacture mortars,that was a good incorporation between alkalin-active materials and mechanism sand,provided theoretical support for integrate utilization in mortar level towards solid construction waste.