Influence of geogrid layer on the integrity of compacted clay liners of landfills

The objective of this paper is to examine the influence of geogrid layer on the integrity of clay liners of landfills. A series of centrifuge model tests were performed on model clay liners subjected to non-uniform settlements with and without a geogrid layer embedded within the top one-third portion of the clay liner moist-compacted on the wet side of its optimum moisture content at 40 g. The model clay liner material has been selected in such a way that it envelopes the material characteristics of the clay liners, which are used for constructing an impermeable barrier in a lining system. By maintaining type and location of the geogrid within the clay liner as constant, the thickness of clay liner is varied to check the possibility of reducing the thickness of a geogrid reinforced clay liner. Digital image analysis technique was employed to ascertain the initiation of cracking and to compute strains both on the surface and along the cross-section of the clay liner with and without any geogrid layer. It was observed that clay liners compacted at moulding water content towards wet side of their OMC found to experience multiple cracking at the onset of non-uniform settlements. Contrary to this, geogrid reinforced clay liner was observed to sustain large distortions and experience only tiny cracks limited up to a location of a geogrid. With an increase in thickness of the clay liner reinforced with a geogrid, geogrid reinforced compacted clay liner was observed to retain its integrity and restrains cracking completely

Studies on the deformation behaviour of randomly reinforced soil liners in a geocentrifuge

This paper deals with the use of a geocentrifuge to model the deformation behaviour of moist compacted soil liners with and without polypropylene tape fibers. A special device for inducing non-uniform settlements during centrifuge test has been custom designed, developed and calibrated. Centrifuge tests were performed in a 4.5 m radius large beam centrifuge facility available at Indian Institute of Technology Bombay. The study is focused in understanding the deformation behaviour of moist compacted soil liners with and without randomly reinforced fibers. Three centrifuge model tests were performed on a compacted soil liner with and without fibers. The influence of the randomly reinforced fibers on the integrity of compacted soils liners at the onset of non-uniform settlements has been demonstrated through centrifuge modeling technique adequately