充分利用桐油防渗性好、附着力强、耐酸碱、耐水、耐日光大气等性能和糯米汁黏糊度高、吸附强、胀度小等特点,将桐油、糯米汁掺入黏土中改善其环境土工特性。渗透、强度、等温吸附和扩散试验结果表明:黏土经桐油、糯米汁改良后,在最优质量比例为90∶5∶5时,渗透系数比未改良土下降2个数量级,同时对金属离子的吸附能力明显增强,尤其对Cu^2+的吸附能力显著提高,并且明显地降低Cu^2+的扩散系数。用扫描电子显微镜(SEM)对未改良土和混合土进行了微观形态结构研究,结果表明桐油能很好地分散并渗入黏土表面形成附着良好的包膜层。萧山黏土混合桐油和糯米汁后极大地改善了其作为黏土衬垫的环境土工特性。
The mechanical and geoenvironmental characteristics of the improved Xiaoshan clay mixed with tung oil and sticky rice juice were investigated. Tung oil with the performance of seepage prevention, strong adsorbability, acid/alkalescence-resistant, water-resistant and sunproof and sticky rice juice with high glutinousness, low expansibility and good tenacity were selected as the additives. From permeability tests, shearing tests, adsorption tests and diffusion tests, it was shown that when the mass ratio of the soil, sticky rice juice and tung oil was 90 : 5 : 5, the mixed soil had lower coefficient of permeability than crude soil by 2 orders of magnitude. Meanwhile, the adsorption capacity of the mixed soil for metal cation distinctly increased, especially for Cu^2+. Morphological microstructure of the mixed soils was studied by scanning electron microscopy (SEM). Tung oil could scatter and penetrate into pores between the soil particles or slices and form solid tenacious polymer film that was strongly bonded to the surface of Xiaoshan clay. It was indicated that better mechanical and geoenvironmental characteristics would be obtained by mixing the clayey soil with tung oil and sticky rice juice.