Research On Reducing Water Absorption Of Solid Waste Foam Concrete By Surface Treatment

In this thesis,the method of surface waterproof treatment is used to reduce the water absorption rate of solid waste foam concrete.The main contents are as follows:(1)Taking ordinary cement,methyl cellulose and water-repellent powder as raw materials,the effect of water absorption rate between JS waterproof system with JS waterproof emulsion and cement-based dry powder waterproofing system with gelatine powder and water was studied.The effect of additive sand on water absorption rate of solid waste foam concrete in JS waterproof system was studies.The best type of basic waterproof coating is JS waterproof coating.According to the single-factor variable control method,the influence of the composition of JS waterproof coating(cement type,water-repellent powder,methyl cellulose,dispersion medium)on water absorption rate of solid waste foam concrete was studied.The optimal formulation of the basic waterproof coating that can reduce the water absorption rate of solid waste foam concrete is determined: 500 g selfleveling cement +2.5g methyl cellulose(MC)+5g water-repellent powder(T80)+100ml JS waterproof emulsion.This provided a basic waterproof coating for the following structures designed to reduce water absorption.(2)From the point of view of composite design,waterproof mechanism of basic waterproof coating(JS waterproof coating)and four different kinds of outer coating(JS waterproof emulsion-BiXuan waterproof agent-RainHong 400 color high elasticity waterproof paint(hereinafter referred to as YuHong 400)and YuShiTu301),were considered with structural characteristics of solid waste foam concrete.Coating process was lay by lay.Three types of structures(JS waterproof coating-Rain Hong 400(or YuShiTu 301),JS waterproof coating-BiXuan waterproof agent-Rain Hong 400(or YuShiTu 301),JS waterproof coating-BiXuan waterproof agent-JS waterproof emulsion-Rain Hong 400(or YuShiTu 301)were designed.Water absorbance rate of solid waste foam concrete after being waterproof treated by these three structural surfaces was reduced to less than 1%.Among them,the structure of JS waterproof coating – BiXuan waterproof agent-JS waterproof emulsion-Rain Hong 400 is best.Under this structure,water absorption rate of solid waste foam concrete was reduced from 60% to 0.50%,with decent degree of 99.17%.(3)Contact angles,X-CT imaging technology,and software platform ORS Visual developed from AI Deep Learning and the Python,was carried to characterize and analyzed solid waste foam concrete after being surface waterproofed.It was found its surface was hydrophobic,the microstructure mechanism of the waterproof layer was studied.The pores of the solid waste foam concrete sample were almost completely blocked after surface waterproof treatment.The pore rate was decreased from 62.81% to 0.95%,with decent degree of 98.49%.This indicated that the structural design of the surface waterproof treatment effectively blocked the pores of the solid waste foam concrete sample block,and reduced the water absorption rate of the solid waste foam concrete sample.This design was in agreement with waterproofing mechanism of various types of coatings as well.