Abstract
A new construction technology has been proposed to increase substantially the vertical stiffness of GRS soil structures to make the deformation of the backfill in service essentially elastic, sufficiently large vertical preloading is applied to the backfill and to keep the stiffness of the backfill in service sufficiently high, preloading is not unloaded to zero, but sufficiently high vertical prestress is maintained within the backfill. In this study, a series of laboratory model tests were performed to quantitatively and separately evaluate effects of preloading and prestressing, and those of the use of tie rods for prestressing. It should be finally underlined that necessary and sufficiently large preload and prestress can be applied to the reinforced backfill. On the other hand, such levels of preload and prestress cannot be applied to usual unreinforced backfill without excessive deformation or even failure, therefore very high stiff backfill can be realized only when applying the preloading and prestressing method to appropriately designed reinforced soil structures.
