多元固废基胶凝材料配比设计及优化研究OA

[Objective]To achieve the goals of resource utilization of bulk solid waste and carbon emission reduction,this study explores the preparation of solid waste-based cementitious materials from bulk industrial solid waste,optimizes the pro-portion design method,improves material performance,and realizes high-value-added application of bulk solid waste.[Methods]Taking compressive strength and flowability as indicators,an orthogonal test was adopted to optimize the composi-tion of multi-solid wastes,and the Dinger-Funk model was further used to optimize the particle gradation of the multi-solid waste powder,thereby obtaining the optimal composition design of the multi-solid waste-based cementitious material.[Results](1)When the slag content was 40%,the mass ratio of fly ash to steel slag was 3∶2,and the contents of desulfu-rized gypsum and carbide slag were both 10%,the 28-day compressive strength of the paste prepared from the solid waste-based cementitious material reached 35.4 MPa,with a flowability of 185 mm.(2)Compared with slag and steel slag,fly ash exhibited better grindability.Fly ash,when ground for 60 minutes,exerted an optimizing effect on the composite gradation of the solid waste-based cementitious material.(3)Mercury intrusion porosimetry tests revealed that the proportion of macro-pores larger than 1 000 nm in the solid waste-based cementitious material was high at the early age.After being filled and re-fined by late hydration products,most of these macropores(>1 000 nm)were transformed into micropores smaller than 50 nm.[Conclusions]The mechanical and working properties of the multi-solid waste-based cementitious materials designed through the combination of orthogonal experiments and the Dinger-Funk model meet the engineering requirements.This design method has positive significance for promoting the application of bulk solid waste.