碱渣改良膨胀土室内试验研究

通过室内试验，探讨利用碱渣作为添加剂对膨胀土改良的可行性和改良效果和碱渣改性土的基本物理力学性质和膨胀性。研究结果表明，随着掺渣率的增加，碱渣改性土的黏性成分的含量降低，粗颗粒含量增加，导致相对密度、液限、塑性指数、自由膨胀率、有荷膨胀量均呈明显减小趋势，这说明碱渣对膨胀土膨胀性的改良有显著效果；碱渣改性土可击实含水率范围较之膨胀土宽，这给碱渣改性土的施工带来很大方便；经过7 d养护后的土样无侧限抗压强度和抗剪强度都显著增加，并在掺渣率为30%时存在一个峰值点。抗剪强度增强主要体现在黏聚力显著增加，而内摩擦角变化不大。

Experimental research on expansive soil improved by soda residue

By laboratory test,the potential use and effectiveness of soda residue as an additive for improving expansive soil are evaluated.The tests research the features of the basic physico-mechanical properties and expansibility of soda residues treated soil.The result shows that the increase of blending residue ratio has made the viscous composition decreased while the percentage of coarse granule increases so that the plasticity index,liquid limit,relative density,free swell index,load swell index are reduced significantly with the increase of soda residue.The test indicates that the soda residue has significant impact on the improvement of the expansibility of expansive soil.The range of compaction water content for soda residues treated soil is larger than expansive soil’s.It brings great convenience for the construction of soda residues treated soil roadbed.After 7 days conservation,there is a remarkable increase in unconfined compression strength and shear strength.Furthermore,a peak appears when the blending ratio of residue has come up to 30%.The remarkable increase in cohesion reflects the shear strength enhancement.However,the angle of internal friction changes little.