Interface frictional properties of geogrid-reinforced pond ash

Abstract

The performance of any reinforced soil (RS) structure mainly depends on the soil-geosynthetic interface friction mechanism. Nowadays, due to the non-availability of conventional backfill materials and unsuitability of locally available soils, the exploration has started to find an alternative material for backfilling. One of such materials is pond ash, generated as a waste by-product from thermal power plants. In this regard, the present work is aimed to find the interfacial frictional characteristics of geogrid reinforced pond ash in terms of coefficient of interface friction (Ci) and pullout frictional factor (f*) by conducting large direct shear test and pullout tests using two biaxial geogrids (GG1 and GG2) of different stiffnesses. From the experimental results, it was observed that the coefficient of interface friction (Ci) values were in the range of 0.84 to 0.66 and pullout frictional factor (f*) values were in the range of 0.43 to 0.28 for the applied normal stresses of 50 kPa, 100 kPa and 150 kPa respectively. Further, GG1 shows higher frictional characteristics compared to GG2 because of its structural geometry and stiffness characteristics.