Influence of grain size distribution and cement content on the strength and aging of treated sandy soils

Abstract

Deep mixing is a method commonly used for various applications ranging from ground improvement and confinement to foundations. With the growth of the use of deep mixing for foundations, it is important to better define the mechanical behaviour and ageing of the material, depending on the cement content and grain size distribution. This study aims to quantify the impact of these parameters as well as the percentage of fines on the mechanical behaviour of the mixed material. A number of unconfined compression tests were carried out. The results showed that it was possible to predict the strength of the mixed material after seven and 28 days of curing, depending on the cement content and the percentage of fines. Also, it was shown that a uniform sand treated with cement presents the same hardening trend for all cement contents. Conversely, a soil with a larger spread of grain size distribution will show different hardening processes, depending on the cement content.

Keywords:

• cement
• unconfined compression tests
• mechanical behaviour
• sand
• deep soil mixing

Acknowledgements

This study is part of a research project funded by Soletanche-Bachy. The authors would like to thank Sonia Fanelli as well as Jean-Louis Tacita for their help in this study.