The results of a model study comparing the dynamic behavior of sound walls supported on concrete cantilever (Caltrans Standard Type 1) and mechanically stabilized earth (MSE) retaining structures are presented. Different backfills representing a loose sand, a dense sand, and a cohesive material were studied. An additional test was runwith the loose sand and inclined reinforcing. The models were tested on a servohydraulic shaking table mounted on a centrifuge. Realistic earthquakes with peak input base accelerations of 0.65 g to 0.75 g were simulated. The sound wall response on the MSE system involvedaccumulated tilting due to nonsymmetrical resistance, and in some cases lift-off and impact of the slab. The behavior of sound walls onType 1 systems was much less sensitive to the backfill type. The MSE systems were generally more ductile than the Type 1 walls; they suffered larger permanent deformations but transmitted smaller accelerations to the sound wall. Sound wall accelerations on the Type 1 wall system were approximately twice those on the MSE system.
Abstract