Research On Sulphate Salty Soil Reinforced By Geopolymer

Chemical saline soil stabilizers is processing the saline soil with a curing agent to meet the requirements about the foundation strength, durability and water stability in different engineering. It’s one of the effective methods of solving the adverse engineering problems such as saline soil dissolving and sinking,salt expansion, corrosion, ect. Geopolymer is one of the materials that be researched very active in recent years. It has a very broad application prospect because of its advantages like abundant raw materials, low cost, energy conservation, environmental protection and so on. On the effect of the alkaline activation, geopolymer can be systhesised by fly ash. The sodium silicate is one of widely used chemical grouting materials with non-toxic, low cost, adaptability, ect. In the same time, sodium silicate is usually used as alkaline activation. This paper studied the mechanical strength of sulphate salty soil reinforced by geopolymer. In order to find the way of modification of geopolymer which used in reinforcement in sulphate salty soil region, the uniaxial compressive strength test, X-ray diffraction, chemical analysis and scanning electronmicroscope were carried out.⑴ When the lime content lower than 8﹪, the sodium silicate can improve the strength characteristic of sulphate salty soil greatly. And the strength of sulphate salty soil reinforced by sodium silicate, lime and fly ash is bigger than those solidified by lime and fly ash. The higher concentration the sodium silicate is, the stronger the reinforced soil. The relationship between them is almost linear.⑵ The mineral composition of sulphate salty soil reinforced by sodium silicate, lime and fly ash is similar to the natural sulphate salty soil. Compared to the natural sulphate salty soil and reinforced sulphate salty soil with lime, fly ash, the diffraction intensity of thenardite decreased and noncrystal material increased. The content of sulfate ion in solidified salty soil reduced sharply.⑶ The alkali-activated action on fly ash caused by sodium silicate, the hydrolytic action of sodium silicate and adsorption between sodium silicate and saline soil generate mass gels. The findings indicate that the increased gels caused to increased contact area and decreased pores among the grains. The mechanism of saline soil reinforced by sodium silicate is due to the reinforcement of the bond strength among the framework grains and formation of three dimensional networks of frame. Meanwhile, the salt expansion of saline soil have been greatly improved because of the sharp reduce in the content of SO42-. The mechanism of saline soil reinforced by sodium silicate is due to the reinforcement of the bond strength among the framework grains and formation of three dimensional networks of frame. Meanwhile, the salt expansion of saline soil have been greatly improved because of the sharp reduce in the content of SO42-.