膨胀土填筑路堤的处理技术

Treatment Technology of Expansive Soil Filling Embankment

公路建设中利用膨胀土填筑路基时,需要注意避免直接将自然膨胀土作为公路路基填料,以防止出现路基变形、沉陷、边坡失稳、结构损坏等重大危害;同时将挖出的大量膨胀土直接弃用将造成严重的环境破坏,造成水土流失及工程经济浪费。依据改进CBR试验快速测定膨胀土强度的方法及膨胀土中掺入石灰加强CBR强度的理论,研究利用膨胀土作为公路路基填料有效性的问题,并给出了掺入7%石灰的膨胀土填芯、膨胀土填芯+黏土包边的路堤填筑组成方案。通过两段实体工程试验,验证改良膨胀土及填筑方案的技术有效性和经济合理性,以达到膨胀土在公路建设中的最佳运用。

Using expansive soil to fill subgrade in highway construction,avoid using natural expansive soil directly as highway subgrade filler,which will cause major hazards such as subgrade deformation,settlement,slope instability,structural damage,etc;At the same time,a large amount of excavated expansive soil will be directly discarded,which will cause serious environmental damage,soil erosion and engineering economic waste.According to the improved CBR test method for rapid determination of the strength of expansive soil and the theory of adding lime to the expansive soil to strengthen the CBR strength.This paper studies the effectiveness of using expansive soil as the filling material for highway subgrade,and gives the composition scheme of embankment filling with 7%lime.Through two sections of physical engineering tests,the technical effectiveness and economic rationality of the improved expansive soil and filling scheme are verified to achieve the best application of expansive soil in highway construction.