| Based on the principles of geopolymerization and resin curing and cross-linking,this study proposes a research idea for the consolidation of sand tailings using geopolymers and resins as gelling agents.In order to investigate the consolidation effect of two gelling agents on sand tailings,a geopolymer-fine powder composite material and unsaturated resin-based polymer.The experimental study of fine powder composite materials explores the influence of factors such as the type of alkali activator,the amount of fine powder added,the amount of glass fiber added and the system of fine powder modification on the compressive strength of geopolymer;Investigated the effects of resin type and relative content,styrene content and curing temperature on the compressive strength of unsaturated resin-based polymers.Taking the type of alkali activator as the test factor and the compressive strength of the polymer test block as the detection index,under the conditions of temperature 80 ℃ and humidity 80%,the alkali activator’s excitation effect on low calcium fly ash is in order from good to poor.For: K-water glass> Na-water glass> industrial NaOH;when K / Na-water glass is used as the alkali activator,the compressive strength of the polymer decreases with the increase of the water glass modulus,and with the mass ratio of fly ash to water glass.the 3d and 7d compressive strength of the K-water glass polymer test block is higher than that of the Na-water glass polymer test block compressive strength;Reduce the water glass’ modulus by adding ROH corresponding to the water glass cation.Compared with KOH,NaOH has low water absorption and high safety.Therefore,Na-water glass is used as the alkali stimulator of fly ash.When the modulus of Na-water glass is 1.0 and the solid content is 36%;The smaller the particle size of the fine powder,the less the amount of fine powder substitution corresponding to the peak of the polymer compressive strength;when the fine particle size is-0.045 mm,0.074-0.045 mm,and +0.074 mm,the fine powder corresponding to the peak of the polymer compressive strength replaces the fine coal,the ash content accounts for 0.19,0.26 and 0.26 of the quality of water glass.Determine the particle size of the fine powder is-0.045 mm,and the compressive strength of the geopolymer-fine powder composite material decreases first and then increases with increase in the amount of glass fiber added.When the amount of glass fiber added is 0.019 and 0.013 of the mass of water glass,the polymer correspondingly obtains the peak compressive strength of 3d and 7d.After modified by the coupling agent,the dispersion of the fine powder becomes better,the number of fine powder groups reduced,and the compressive strength of the polymer is significantly improved.The polymer test block achieved the peak compressive strength,and the-0.045 mm fine powder corresponding to the polymer obtains the highest compressive strength.The effect of the type and relative contents of resins on the compressive strength of the polymer were examined.The results show that under the curing condition of 80 ℃,with the increase of the mass ratio of the fine powder to the resin(η=1.0-2.5),the compressive strength curve of the epoxy resin-based polymer shows an upward convex shape,and the compressive strength curve of the unsaturated resin-based polymer shows a concave shape change regular,and the compressive strength of unsaturated resin-based polymer is greater than that of epoxy resin-based polymer.Taking the type of resin as the test factor,and the compressive strength of the unsaturated resin-based polymer as the detection index;Under the curing condition of 80 ℃,when the mass ratio of fine powder to 168 unsaturated resin is 1.0-1.6,1.7-2.5 and 2.6-3.0,the relative content of resin decreases,the main factors that determine the compressive strength of the polymer are different,the compressive strength curve shows different changing rules.When the mass ratio of fine powder to resin is 2.5,the compressive strength of the polymer is the largest,which is 87.43 Mpa.The effect of the amount of styrene addition on the compressive strength of the unsaturated resin-based polymer-fine powder composite test block was examined;when the mass ratio of fine powder to resin is 3.0,when the amount of styrene added accounted for 6.5% of the mass of the unsaturated resin,the polymer test block obtains the maximum compressive strength value,is about 85 MPa;when the addition amount of styrene is too high,the excess styrene will self-polymerize into polybenzene ethylene and volatilization of styrene will cause volumetric shrinkage of the polymer and decrease the compressive strength.The effect of curing temperature on the compressive strength of unsaturated resin-based polymer-fine powder composite materials were examined;the changing law of polymer compressive strength curve under different curing temperatures were different;curing different temperatures,different volatilization of low-molecular substances in the resin slurry,different decomposition rates of the curing agent and resin curing rate,resulting in differences in the size and uniformity of the polymer network structure;when the curing temperature is 60 ℃,the mass ratio of fine powder to resin when it is 2.4,the compressive strength of the polymer is the largest at 94.63 Mpa.Based on the single-factor test,the internal interaction of the three factors was analyzed by response surface method.Through the experimental analysis,it can be seen that the interaction of the amount of styrene added and the mass ratio of fine powder to unsaturated resin have a significant effect on the compressive strength of the polymer;The model obtained the best test formula: the amount of styrene added accounted for 5.5% of the resin mass,the curing temperature was 36°C,the mass ratio of fine powder to resin was 1.7,and the error between the verification test result and the simulation value was less than 2%.The compressive strength of geopolymer-fine powder composite material meets C20 concrete standard,and unsaturated resin-based polymer-micropowder composite material meets the strength requirements of JC/T 908-2013 and GB 50212-2002.There are 46 figures,19 tables and 107 references in this paper. |
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