矿渣碱激发胶凝材料固化盐渍土试验研究

Experimental Study on Solidification of Saline Soil Using Alkali-activated Slag Materials

为解决盐渍土路基铺设存在的溶陷、变形等问题,采用矿渣碱激发胶凝材料固化的方法对盐渍土的综合性能进行优化。通过击实试验和无侧限抗压强度试验研究了矿渣碱激发胶凝材料对盐渍土抗压强度的影响,并利用XRD和SEM分析了试样的物相组成和微观形貌。结果表明,矿渣碱激发胶凝材料固化盐渍土效果显著,掺入适量矿渣碱激发胶凝材料盐渍土的抗压强度和水稳定性显著改善,反应产物中C-S-H凝胶相含量明显增多,形成了结构稳定的胶凝-网状混合结构。水化反应生成了新的水化产物片状晶体和针棒状晶体,形成了C-S-H凝胶相和钙矾石的结构。

To solve the problem of subsidence and deformation in the paving of saline soil roadbed, the solidification through alkali-activated slag is adopted to improve the engineering performance of the saline soil. The compaction test and unconfined compressive strength test are used to study the effects of alkali-activated slag on the compressive strength of saline soil, and the X-ray diffraction（XRD） and scanning electron microscope（SEM） are used to characterize the phase composition and microstructure of samples. The results show that the solidified roles of alkali-activated slag is remarkable.A moderate amount of alkali-activated slag can effectively improve the compressive strength and the water stability of saline soil. The morphology of the C-S-H gel phase and ettringite is assoiciated with the crystal plate and needle stick crystals, respectively.