Experimental and Numerical Investigation on Undrained Behavior of Geogrid Reinforced Pond Ash

Abstract

Geogrid reinforced pond ash is an effective composite material, which can be utilized as a construction material for various geotechnical engineering purposes. In this study, both experimental and numerical investigations have been carried out on shear strength characteristics of unreinforced and geogrid reinforced pond ash samples under undrained condition. Consolidated undrained (CU) triaxial tests have been performed on 100 mm x 200 mm cylindrical ash samples under static compressive loading. The investigations include the influence of confining pressure and number of geogrid layers on stress–strain characteristics of pond ash. Finite element package PLAXIS 2D was used for numerical simulation of unreinforced and geogrid reinforced pond ash models under undrained condition. Both experimental and numerical results show that the peak deviatoric stress increases as confining pressure increases for both unreinforced and reinforced ash samples. For a particular confining pressure, with increase in number of geogrid layers the value of peak deviatoric stress increases and its corresponding strain decreases. The increase in peak deviatoric stress is about 27%–93% for one-layer geogrid reinforced sample and 37%–117% for two-layer geogrid reinforced sample compared to unreinforced ash sample. Finite element analysis shows a good match in the stress–strain plot with the experimental result.