[关键词]
[摘要]
文中使用将水泥与化学固化剂和机械力脱水三种方法相结合的方式对东湖淤泥进行固化处理,通过界限含水率、强度试验(包括CBR和直剪试验)以及渗透试验研究了在使用水泥固化过程中水泥掺量、养护龄期以及压实度对固化土工程性质的影响。结果发现:仅使用化学固化剂和机械脱水固化处理后的淤泥属于高液限粉土,CBR强度低,不能满足路基填料的要求。使用水泥能够有效提高一次改性固化土的CBR强度和直剪黏聚力,养护龄期对CBR强度影响很小,而水泥掺量、养护龄期和压实度对内摩擦角的影响均不大。此外,在水泥掺量从0 %增大到8 %的过程中,渗透系数呈现出先增大后减小的趋势,在水泥掺量为2 %时达到最大值。综合分析,在水泥二次改性过程中,为符合路基填筑要求,水泥掺量宜为8 %,压实度宜大于92 %。
[Key word]
[Abstract]
This paper uses a combination treatment of cement, chemical stabilization and mechanical dehydration to stabilize the East Lake sludge. The effect of cement content, curing age and compaction degree on soil engineering properties has been researched by limit moisture test, strength test (including CBR and direct shear test) and permeability test. The results showed that the East Lake sludge stabilized by chemical stabilization and mechanical dehydration is high liquid limit silt with low CBR strength, and cannot meet the requirements of subgrade. Cement can effectively improve the CBR strength and cohesion of the secondary modified cement stabilized soil. Curing age contributes little to CBR strength. Cement content, curing age and compaction degree have little effect on internal friction angle. In addition, permeability coefficient increased at first and then decreased in the process of cement content increasing from 0% to 8%. The cement content is 2% when permeability coefficient reaches the maximum. According to the comprehensive analysis in the process of sludge modified by cement, the cement content should be 8%, and compaction degree should be more than 92% to meet the requirements of subgrade filling.
[中图分类号]
[基金项目]
国家自然科学基金资助项目(51479148); 中建三局投资发展有限公司科技项目(250000270)