不同配比下机场高填方边坡重塑土变形特性研究-《建筑科学与工程学报》

文章信息/Info

Title:: Study of Deformation Characteristics of Remoulded Soil at Airport High Fill Slope Under Different Proportions

Author(s):: ZHU Yan-peng, JIANG Huai-jun, YANG Xiao-hui, ZHU Jun-chuan, SHI Zhan-bin; Key Laboratory of Disaster Prevention and Mitigation in Civil Engineering of Gansu Province, Lanzhou University of Technology

Keywords:: high fill slope; silty clay; red sandstone; deformation characteristic; hyperbola function model; secant modulus

摘要:: 为研究不同配比下某机场高填方边坡重塑土体在最优含水率条件下的压缩变形特性，采用固结仪对40组160个试样进行压缩试验，总结出孔隙比垂直荷载曲线变化规律。通过分析土体在侧限条件下垂直压应力与垂直压应变关系，拟合出最佳应力应变曲线公式，并推导出试验土体所符合的本构关系，最后进行沉降预测。结果表明：粉质黏土与红砂岩质量比为2∶8的土体压缩性比质量比为4∶6的土体压缩性低，更适合做高填方填料；不同配比的土体在各压实度下的应力应变曲线均符合双曲线函数模型；相对于规范推荐法，采用割线模量法得到的沉降量计算值与实测值更为接近，具有较好的适用性。

Abstract:: In order to study the compression characteristics of remoulded soil in an airport high fill slope under different proportions and the condition of optimum water, the compression test which contained 160 specimens in 40 groups was carried with compression apparatus, and the change rules of void ratio-vertical load curves of soils under lateral confinement condition were summarized.Through analyzing the relation between vertical pressure and vertical strain of remoulded soil, the optimum stress-strain curve formula was fitted, and the constitutive relation suit for the test soil was derived, at last the settlement was forecasted. The results show that the compressibility of remoulded soil with 20%(mass ratio) silty clay and 80% red sandstone is smaller than that of remoulded soil with 40% silty clay and 60% red sandstone, so the former is fit for high fill filler. The pressurestrain curves of remoulded soil under the condition of different mixture ratio and different compactnesses are all suit for hyperbolic function model. Compared to the standard recommendation method, the calculation values of settlement by secant modulus method are closer to measured values of settlement, and have better applicability.