Sand properties at the construction work sites play an important role in both the design and the construction phases of projects. It is important sometimes to think about modifying the sand (soil) properties in order to increase its strength and compaction to levels that enable it to carry heavier loads, experience less settlement and perform much better during and after construction.
Fluid viscosity is considered one of the major factors affecting sand performance. Treating sand (soil) at the work sites with different viscosity level fluids improve some of its major and important characteristics. This paper presents the affect of various levels of fluid viscosity on sand through two characteristics: shear strength parameters of the sand and the sand compaction.
Laboratory experiments were carried out in professional geotechnical laboratory using: the direct shear test apparatus for the shear strength parameters of sand, and the modified proctor test for the sand compaction. Five different sand types have been used in the sand compaction tests and one sand type in the direct shear. Three fluids were used with different viscosities.
It was found that, for the modified proctor test, the fluid viscosity has a significant effect on each the optimum fluid content and the sand maximum dry density. The sand maximum dry density was found to be increased as the fluid viscosity increases, and the optimum fluid content was found to be decreased as the fluid viscosity increases. On the other hand, for the direct shear test, the sand apparent cohesion was found to be inversely proportional to the fluid viscosity; while the sand internal angle of friction was found to be directly proportional to fluid viscosity up to a certain viscosity then it has a inversely proportion with the fluid viscosity.