ABSTRACT
The study investigates the effectiveness of sand-rubber mixtures (SRM) as trench infill material for mitigating ground-borne vibrations induced by impact pile driving. Full-scale field experiments were conducted at a site 20 km north of Chennai, where the subsurface primarily consists of clayey strata within the top 3 m, underlain by sandy strata. Both open trenches and SRM-infilled trenches (containing 30% rubber by weight) were implemented as vibration screening measures. Acceleration time histories were recorded at multiple locations before and after the trenches during pile driving. The experimental results indicate that SRM-filled trenches exhibit vibration attenuation comparable to that of open trenches, particularly in soft to medium stiff clay and loose to medium dense sand layers. Additionally, finite element (FE) simulations using PLAXIS 2D, employing the Mohr-Coulomb constitutive model for soil and SRM layers, captured the predominant trends in the measured acceleration response, although the numerical model slightly overestimated vibration amplitudes.
