Study On The Compressive Properties Of Fly Ash Geopolymer Concrete

In order to alleviate the current situation of traditional Portland cement industrial pollution problems and improve the utilization rate of fly ash in China,this paper focuses on the replacement of cement fly ash as cementitious materials were studied.Based on the mechanical properties of the traditional experimental study of mechanical properties of this dissertation is also on the Fly Ash Geopolymer concrete constitutive relationship research to provide reliable support for improving the performance of fly ash geopolymer concrete and related experimental data accumulated for this new type of material preparation and engineering application have guiding significance.The main contents of this dissertation are as follows:1.Fly Ash Geopolymer cementitious material preparation: including the proportioning design of cementitious materials and the mechanical properties test.The cementitious material mix design including fly ash,cement,superplasticizer,alkali and water ratio is determined by the basic performance experiments include adhesive;glue cement and water reducer compatibility experiment,mortar strength test(3d intensity and 28d).Experiments on the compatibility of Fly Ash Geopolymer cementitious materials and superplasticizer,the saturation point of experimental methods were determined.The results show that: there are significant differences in different reducing agent and compatibility of geopolymer cementitious material the,The Calcium Lignosulfonate with good compatibility,naphthalene superplasticizer of polycarboxylic superplasticizer and its compatibility with the worst;while the experimental study also shows that the temperature on the Fly Ash Geopolymer cementitious material flow has a certain impact,with the increase of alkali,liquidity and slightly weakened;the mechanical properties of mortar surface,when the alkali dosage of 10% Fly Ash Geopolymer cementitious material reaches the maximum strength.2.Fly ash geopolymer concrete working performance and strength test: this part mainly focuses on the fly ash geopolymer concrete specimens 3d and 28 d compressive strength test and slump test,research shows that NaOH in the admixture of 10% reachedthe maximum concrete compressive strength;the study also shows that lignin calcium content is 0.4% concrete the biggest slump,the workability of the best.3.Study on constitutive relationship of 3.fly ash geopolymer concrete with water binder ratio and loading rate for the experimental parameters,the fly ash geopolymer concrete analysis of the stress-strain curve with peak stress,peak strain,elastic modulus and Poisson's ratio,and then analyzes two kinds of concrete experimental variance experiment.Show that the loading rate and water cement ratio on the fly ash geopolymer concrete compressive constitutive relations law: loading rate of 1.0mm/min peak stress reached the maximum water cement ratio increased to the peak stress decreases,the elastic modulus decreases.