针对目前膨胀土化学改良方法存在的缺陷，提出了一种采用风化细砂对膨胀土胀缩特性进行物理改良的方法．通过在膨胀土中掺入不同比例的风化细砂，并进行膨胀试验和收缩试验，研究不同掺砂比例对膨胀土的膨胀和收缩指标的影响．通过对不同比例掺砂膨胀土的胀缩特性数据分析发现，随着掺砂比例的增加，膨胀和收缩指标减小．当掺入风化细砂的比例达到10％时，对胀缩指标影响最显著，且胀缩总率为0．67％，自由膨胀率为31％，达到路基填料的标准．综合经济性和实用性考虑，最佳掺风化砂比例为10％．%Based on the defects of expansive soil chemical modification methods, a physical improvement meth- od mixing weathered fine sand with expansive soil is proposed. Weathered fine sand mixed with different pro- portions of expansive soil, expansibility index and shrinkage index experiments have been made, and the influ- ence of different sand ratios on expansive soil expansibility indexes and shrinkage indexes has been concluded. Analyzing expansibility and shrinkage characteristics of expansive soil of different proportions of dope fine sand data, the doped sand is effective to inhibit the expansion and contraction of expansive soil. With the increasing in the proportion of doped sand, expansibility indexes and shrinkage indexes are both decreasing. When the incorporation of a weathered fine sand ratio reached 10% , the influence on the swell-shrinking index is the most significant. The swell-shrink total ratio is 0.67% and the free expansion rate is 31% , achieving the standard of roadbed filler. In the comprehensive economic and practical view, the optimum mix proportion of weathered fine sand is 10%.
展开▼
