某高速公路穿越泥岩地层，该地层泥岩风化程度高，直接作为路基填料填筑时，易产生路面鼓包、路基不均匀沉降、承载力不足等工程问题，严重威胁道路运输安全。为了消除泥岩风化路基土的不良特性，采用了石灰、粉煤灰、水泥对泥岩风化路基土进行室内改良试验研究。利用电子显微镜观察改良土微观结构，并应用 IPP 软件提取 SEM 中改良土体微观参数，研究分析泥岩改良土的微观改良机制，与改良土改良效果试验对比，分析3种改良剂改良效果。结果表明，石灰改良土的孔隙比降低，孔隙改良效果明显；粉煤灰改良土整体的孔隙比与素土基本持平；水泥改良土孔隙改良效果差，但是孔隙中生长了大量的钙矾石，使得水泥改良土的宏观强度性质有较大提高。%One highway through the purple mudstone stratum with great weathering degree of the mudstone,it is easy to generate engineering problems such as road surface bulge,uneven settlement, and insufficient bearing capacity when it is used as subgrade filling directly,which is a serious threat to road transportation safety.In order to eliminate the bad properties of weathering mudstone soil, lime,fly ash and cement are adopted for indoor experimental study of weathering mudstone soil im-provement.Using electron microscope to observe the microstructure of modified soil,microscopic pa-rameters in SEM by IPP software are extracted,the micro mechanism of modified soil is studied,and the modified results are contrasted by three kinds of modifiers.The results show that the void ratio of lime modified soil is obviously decreased and the modified result is good.Fly ash modified soil's void ratio is almost equal to that of Prime soil.The pores of cement modified soil are not modified greatly, but make the growth of a large number of ettringite crystal in pores,the macroscopic strength proper-ties of cement modified soil is improved greatly by the reason.
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