压实作用对桂林重塑红粘土渗透性与强度指标的控制作用分析

Influence of Degree of Compaction on the Permeability and Shear Strength of Remolded Guilin Laterite Soils

红粘土作为一种典型的特殊土,在广西桂林市广泛分布,为保证红粘土路基的稳定性,针对桂林红粘土,通过湿法击实制备最佳含水率下的粘土试样,通过室内变水头渗透试验,发现红粘土渗透系数随着压实度增大呈指数关系下降;根据室内三轴试验,得到不同压实度下红粘土的抗剪强度指标变化规律,随着压实度增高,粘聚力呈指数函数关系增大,内摩擦角呈二次函数关系先增大后减小;综合所得结果分析了压实作用对广西红粘土性能的影响机理,建议路基施工中应控制压实度在94%以上。

Laterite soil is a typical special soils and it is widely distributed in？Guilin area.In order to ensure the stability of laterite soil subgrade,？the remolded Guilin laterite soil samples under the optimum moisture content were prepared from the wet side and the permeability of the soil samples were tested with falling head method.An exponential reduction in the permeability magnitude with the increase of degree of compaction.Under triaxial test conditions,the tested cohesion value increases exponentially with the increase of degree of compaction.The internal friction angle,however,has a quadratic polynomial relationship with the degree of compaction：it increases and then reduces with the increase of the degree of compaction.The paper recommends the degree of compaction of Guilin laterite soil for the roadway subgrade should be greater than 94%.