Abstract: The gravel soil along Mianyang-Jiuzaigou express way was selected to study the impact of water content and sand content on the performance of dimeric material modified gravel soil. The experiment results show that dimeric material has significant impact on the improvement of cohesion and water resistance of gravel soil; the water content has obvious effect on cohesion force of the reinforced soil, and when the water content is the limit value of the gravel soil, the cohesive force reaches the maximum value, which is 135 times as large as that of the natural gravel soil; but the water content is insensitive to the internal friction angle of the reinforced soil. With the increase of sand content, the shear strength parameters of the reinforced soil show a tendency of increase first and then decrease. When the sand content is 5%, the internal friction angle of soil samples increases to be the maximum.

Key words: highway engineering, gravel soil, moisture content, sand content, shear properties, water resistance

摘要： 选择绵九高速公路沿线碎石土进行试验，研究了不同含水率和掺砂量对双聚材料改良碎石土性能的影响。结果表明：双聚材料对提高碎石土的内聚力和耐水性有显著作用；含水率对加固土内聚力影响显著，当含水率为碎石土塑限值时，粘聚力达到最大值，是天然碎石土的135倍，但含水率对加固土内摩擦角的影响不敏感；随着掺砂量的增加，加固土的抗剪强度参数均呈现先增加后减少的趋势，当掺砂量为5%时，土样的内摩擦角提高到最大值。

关键词: 道路工程, 碎石土, 含水率, 掺砂量, 剪切特性, 耐水性