掺砂软黏土一维压缩和渗透性状研究

Research on One‑dimensional Compression and Permeability Properties of Sand‑doped Soft Clay

针对真空预压法加固软黏土地基存在深层土体加固效果差的问题,提出掺砂改良软黏土压缩和渗透特性的方法。通过室内掺砂软黏土的一维固结渗透试验,探讨了掺砂率对软黏土压缩性状和渗透性状的影响规律,建立了掺砂土体的归一化压缩公式,得出了如下结论:不同掺砂率土体的压缩曲线形态相近;与初始孔隙比相比,1600 kPa荷载下的孔隙比减小幅度均在45%左右;可根据参数e/eL对压缩曲线进行归一化处理;孔隙比相同时,渗透系数随着掺砂率的增大而增大;掺砂土体的压缩系数、压缩指数和渗透指数均随掺砂率的增加呈幂函数减小规律。

In order to solve the existed problem of poor reinforcement effect of deep soil in soft clay foundation reinforced by vacuum preloading method,a method of sand mixing to improve the compression and permeability characteristics of soft clay was proposed.In this paper,one‐dimensional consolidation and permeability tests of sand-doped soft clay are carried out indoors,the influence of sand ratio on the compression and permeability properties of soft clay is discussed,the normalized compression formula of sand-doped clay is established.The results are listed as follows:compression curve morphology of soils with different sand mixing ratios is similar.Compared with the initial pore ratio,the pore ratio decreases by about 45%under the 1600 kPa load.The compression curves can be normalized according to the parameter e/eL.As the pore ratio is the same,the permeability coefficient increases with the increase of sand mixing ratio.The compression coefficient,compression index and permeability index of sand-doped soil decrease by power function with the increase of sand mixing ratio.