Studies on scaling and instrumentation of a geogrid

Abstract

The scaling down of geosynthetic materials is essential in small-scale physical modeling studies in order to obtain the correct response of prototype structure. In this paper, similitude conditions concerning modeling of geosynthetic materials in 1 g and Ng conditions are examined with an emphasis on geogrids. In order to model soil–geosynthetic behavior satisfactorily, it was observed that there is a substantial requirement of modeling geosynthetic materials for studies pertaining to the behavior of reinforced soil structures. Secondly, one of the selected model geogrids was instrumented with special type of tiny strain gauges adhered to base material formed with strengthened epoxy adhesive and calibrated. Guidelines are presented for selecting scaled-down geogrids along with demonstration of an application through a centrifuge model test on geogrid reinforced clay liner and calibration aspects of the model geogrid. The geogrid layer was used as a reinforcement inclusion within the model clay liner subjected to non-uniform settlements in a geotechnical centrifuge. The results indicated that the model geogrid is required to be calibrated several times by loading and unloading cycles till a reproducible response is accomplished. The measured tensile strength and observations made during the centrifuge test were reported. The results revealed that the strain gauges can be used to measure in-plane tensile strength characteristics of embedded geogrid within the soil, however the influence of base material on the tensile strength–strain behavior of the geogrid need to be considered.