采用直接观察与图像色彩参数对比相结合的方法，对桐油和糯米汁改良后的粉土外观色彩还原性进行定量的对比和分析。首先制备不同质量比的改良土样，并静置养护至色彩稳定。然后采用直接观察方法首先对改良土外观色彩的变化予以初步判断。接着，在固定光源条件下，对土样表面色彩L*a*b*参数进行软件提取，利用色差计算公式计算改良前后土样的明度差、彩度差及色差值。结合两种方法，分析桐油和糯米汁对改良土外观颜色变化的影响。结果表明，改良土中，糯米汁的掺入有使土体轻微发白的作用，桐油的掺入有使土体明显变黑的作用，当桐油、糯米汁和土三者质量比为5∶10∶85时，改良土体颜色与未改良土保持最佳的一致性；而当色差值ΔE>5时，改良土样存在肉眼可观察到的颜色变化。因此，在土遗址加固改良工程中，应保证改良前后土体色差ΔE<5；而采用桐油和糯米汁对遗址土体进行改良时，应采用5∶10∶85的质量配比。

In order to qualitatively and quantificationally contract and analyze the influence of soil surface color treated by tung oil and sticky rice juice, the methods of direct observing and color parameter comparison are used. Firstly, soil specimens treated by tung oil and sticky rice juice in different mass ratios are prepared and maintained till the surface color invariable. Secondly, the change of the soil surface color is qualitatively estimated by observing, then the photograph of the specimens is taken under fixed light source to obtain the L*a*b* parameters including the lightness difference, the chroma difference and the total color difference, and the influence caused by the tung oil and sticky rice juice are quantificationally analyzed. The results show that the sticky rice juice could turn the treated soil white and bright slightly while the tung oil could turn the soil black and dark obviously. The treated soil specimen at the mass ratio (tung oil to sticky rice juice to soil) of 5∶10∶85 has the closest surface color compared to the untreated soil specimen. When the color difference ΔE>5, the difference of the surface color could be observed with naked eyes. The color difference of the treated and untreated soil should be ensured at ΔE<5 in the conservation project of the earthen sites. When using tung oil and sticky rice juice to improve the soils, the mass ratio should be controlled at 5∶10∶85 to guarantee the best consistency of the surface color.