为了研究陕北地区毛乌素沙地中砒砂岩与沙复配土颗粒的胶结作用力，将砒砂岩与沙按不同的体积比配制复配土，采用拉曼光谱仪测试复配土粉末的拉曼光谱；根据复配土中化学成分SiO2在拉曼位移为464 cm-1处的特征峰峰位随砒砂岩含量的变化，研究了土体颗粒胶结作用力的变化。结果表明：沙的峰位为464.5 cm-1，随着砒砂岩含量增加，峰位逐渐减小；这是因为沙中砒砂岩的添加使得砒砂岩中的小颗粒占据了沙中部分大颗粒的位置，颗粒间的距离变大，颗粒间相互牵引而产生拉应力，从而导致拉曼特征峰红移；当砒砂岩与沙的体积比为1∶1时，峰位减小到463.6 cm-1；当砒砂岩与沙的体积比为7∶5时，土体结构发生坍塌，变得紧实，土体颗粒之间产生了压应力，导致峰位突然增大到464.2 cm-1，之后土体结构趋于稳定；随着砒砂岩含量进一步增加，仍有砒砂岩小颗粒对沙大颗粒的置换作用，导致拉应力逐渐明显，峰位不断减小，当复配土为全砒砂岩时峰位为463.1 cm-1。实验结果证实了可将SiO2分子拉曼光谱特征峰峰位的移动用于研究复配土颗粒间的胶结作用力。

To study cementation force of compound soil mixed by soft rock and sand in Mu Us sand land in northern Shaanxi, we mix the soft rock and sand in different proportions to prepare compound soil, and then test the Raman spectra of the compound soil. According to the peak position of SiO2 at Raman shift 464 cm-1 varying with contents of the soft rock in the compound soil, we study the change of the cementation force of the compound soil particles. The results show that the peak position of the sand is 464.5 cm-1. With the increase of the content of the soft rock in the compound soil, the peak position decreases. This is because that the addition of the soft rock causes small particles in the soft rock to replace the position of large particles in the sand, the distance between soil particles increases, and the tensile stress appears due to tow between particles, which leads to the red shift of the Raman characteristic peak. When the volume ratio of soft rock to sand is 1∶1, the peak position decreases to 463.6 cm-1. When the volume ratio of soft rock to sand is 7∶5, the soil structure collapses and becomes firm, which results in the generation of compressive stress between particles. The compressive stress results in sudden increase of the peak position to 464.2 cm-1. Then the soil structure becomes stable. With the further increase of the soft rock content, there is still the replacement of samll particles of soft rock to large particles of sand, the tensile stress is obvious gradually, and the peak position constantly decreases to 463.1 cm-1 when the compound soil is sand. It is proved that the shifting of the peak position of SiO2 in Raman spectra can be applied to the study of cementation force between particles in compound soil.