消石灰、水泥改良粉土的强度及变形特性研究

Strength and deformation characteristics of silt modified with slaked lime or cement

以泰州市东风路南段的低液限粉土为研究对象,通过添加消石灰、水泥及消石灰和水泥对粉土进行改良,并对改良后的粉土进行室内研究。研究结果表明:消石灰、水泥及消石灰和水泥改良粉土的无侧限抗压强度均有大幅度提高;改良粉土的无侧限抗压强度均随养护龄期增长逐渐增大,但在14~28 d之间的增长速率较大,28 d之后的增长速率较小;改良粉土的无侧限抗压强度随压实度的增加明显提高;消石灰和水泥联合改良粉土抵抗变形的能力显著提高;3%消石灰+5%水泥联合改良粉土不仅能够满足路基填料的设计要求,且比较经济,是较佳改良方案。试验结果具有参考价值,实际工程中可以依据强度要求确定不同的石灰+水泥掺量。

Taking the low liquid limit silt located in Taizhou area as the research object, we improved the silt by adding slaked lime, cement and both, and carried a laboratory experiment on the modified silt. Results show that the unconfined compressive strength of the modified silt got dramatic improvement, which increased with the growth of the ages. Especially between the 14 to 28 days, the growth rate was larger. And after the 28 th days, the growth rate was smaller. The unconfined compressive strength of the modified silt was dramatically improved with the increase of compactness. The ability of deformation resistance of silt treated by slaked lime and cement got great improvement. Silt modified with 3% slaked lime and 5% cement can meet the design requirements of roadbed packing, and it is also economical, which is a better improvement scheme. The test results have certain reference value, and the mixing amount of slaked lime and cement can be determined according to the strength requirement of practical engineering.