نوع مقاله : مقاله کامل پژوهشی
1 گروه ژئوتکنیک، دانشکده عمران، دانشگاه آزاد اسلامی تبریز
2 گروه عمران، دانشکده فنی، دانشگاه آزاد اسلامی تبریز
3 گروه عمران دانشگاه آزاد تبریز
عنوان مقاله [English]
The process of forming cemented alumino-silicate bonds in the presence of an alkali activator is referred to as geopolymerization, which has been proposed as the third generation of binders after lime and cement to improve problematic soils. In the present study, this technique was used to improve the green marl soil and the mechanical properties of the modified samples were evaluated with the uniaxial tests. For this purpose, zeolite and metaclay were used separately as sources of alumina silicate and sodium hydroxide solution as alkali activator, and the effect of additives, alkali activator molarities and curing time on the compressive strength of the samples was investigated. The test results indicate the appropriate effect of the geopolymerization in improving the resistance characteristics of carbonate clay, so that in the optimal samples of zeolitic and metaclayey geopolymer, the compressive strength of the samples is 12 and 7 times of the pure green marl sample, respectively. The optimal concentration of alkali solution for zeolite and metaclay geopolymeric samples is 12M, and enhancing the molarity to more than 12M in zeolite geopolymeric samples has negative effect on the uniaxial strength of the samples, but it is not significant in metaclay ones. At concentrations above 4M of alkaline solution for all weight percentages of zeolite or metaclay, the uniaxial strength of zeolite geopolymeric samples is higher than that of metaclay ones. Finally in geopolymer samples, the failure strain has decreased by 25 to 50% compared to the pure green marl sample.