GGBS及其激发剂固化合肥湖积软土的试验研究

将CaO和石膏作为激发剂掺入粒化高炉矿渣微粉(GGBS)制备GGBS+CaO+石膏固化黏土,通过无侧限抗压强度试验研究固化黏土的强度变化规律,基于正交试验确定GGBS、CaO和石膏三掺量的最佳配合比。研究表明:单掺GGBS对软土有一定的固化效果,但固化速度慢、效果差;将CaO、石膏和GGBS混合后固化效果明显,固化土3d(天)即可形成一定强度。养护28d后,固化黏土最大强度可以达到2.9MPa;利用极差分析得出石膏掺量变化对抗压强度的影响最大,GGBS次之,CaO影响最小;GGBS、CaO和石膏三掺量固化黏土最佳配合比分别为11%、3.5%和5%。上述研究成果为在合肥滨湖地区应用矿渣类软土固化剂提供了理论依据。

Experimental Study of Lacustrine Soft Soil Solidification in Hefei Area by adding GGBS and Activators

Calcium oxide (CaO) and gypsum as activators are added into granulated blast furnace slag (GGBS) to prepare GGBS plus CaO and gypsum solidified clay. Study of solidified clay intensity variation was carried out through unconfined compressive strength experiment. The optimum mix ratio of three contents GGBS, CaO and gypsum was obtained based on orthogonal experiment. Experimental results show that single GGBS has only a bit effect on soft soil solidification with slow solidification speed. The solidifying effect is obvious by mixing CaO, gypsum and GGBS, and the solidified soil will present certain intensity after three days. The maximum strength of solidified soil will reach 2.9MPa after 28 days. Based on the range analysis, the maximum effect on compressive strength is contributed by gypsum, next one comes from GGBS, calcium oxide contributes the minimum impact. It is found that the optimum mix ratio of solidified soft soil is 11% GGBS, 3.5% CaO and 5% gypsum. Above results provide theoretical reference for application of GGBS to solidify lacustrine soft soil in Hefei lakeside new district.