Static and dynamic properties of a lightly cemented silicate-grouted sand

This paper describes the results of an experimental investigation on the behaviour of a lightly grouted loose medium sand under both monotonic and cyclic loading. The experimental programme in the present study was carried out on both untreated and treated sand specimens stabilized with a silica-based grout, and comprises isotropic triaxial compression tests equipped with bender elements, drained triaxial monotonic shearing tests, and undrained cyclic tests in a simple shear (SS) apparatus. The results highlight that the weak cementation level induced by chemical treatment was sufficient to moderately increase small-strain stiffness and stress–dilatancy of the grouted sand during drained monotonic shear. A small cohesion intercept was observed in the analyzed failure envelope, while cyclic liquefaction resistance exhibited a much more significant increase, with a different pattern of behaviour between low and high stress levels. Finally, undrained cyclic SS test results evidenced that silicate grout employed in this research improves undrained cyclic shear strength in a manner similar to densification of the same material up to a density index of approximately 75%.