Centrifuge model tests on geogrid reinforced soil walls with marginal backfills

摘要

For the past three decades, there is steep increase in the construction of geogrid reinforced soil walls. Due to non-availability of granular materials, in many situations, marginal backfills are being used in the construction of geogrid reinforced soil walls. The objective of this paper is to address the deformation behaviour of geogrid reinforced soil walls constructed with three different backfill materials by performing model tests at high gravities using a large beam centrifuge facility at IIT Bombay. Three different backfill materials having varying percentages of fines were formulated and used in the present study as backfill soils. A short series of centrifuge tests on geogrid reinforced soil vertical walls with a wraparound facing was carried-out at constant acceleration by varying backfill type and by maintaining height of the wall, type, spacing and length of geogrid reinforcement layers as constant. Surface settlements and facing movements were monitored. The peak reinforcement strains and normalized face movements were found to be greater with the addition of fines in backfill. The presence of fines in backfill shifted the peak strain concentration towards the top of wall.