STUDY OF COMBINED EFFECT OF GEOGRID AND WASTE PLASTIC STRIP REINFORCEMENT ON THE BEARING CAPACITY OF SAND by Alok Sharma
Abstract
Improvement of bearing capacity of soil can be achieved by using different types of reinforcement such as geogrids, geocells and fibers of different material etc. In the recent years, experts have extensively used geosynthetic materials as reinforcement for improving the bearing capacity of soil. Fibers/Strips have high tensile strength hence acts as good reinforcement material and increases strength of the soil because shear stresses in soil mobilize tensile resistance in the fibers. So in this study an effort has been made to investigate the combined effect of geogrid and plastic strips from waste water bottles having aspect ratio 3 as reinforcing material in sand. The main emphasis of this study is to explore the utilization of waste plastic along with geogrid for strength improvement of cohesionless soil. Plastic waste being a non-biodegradable material poses serious threat for its eco-friendly disposal and its use for geotechnical purposes may be a suitable solution. During Load settlement tests optimum depth of first geogrid layer from the bottom of footing was decided and found to be at 0.5 B, where B is the width of footing and increase in bearing capacity was observed to be 100% as compared to unreinforced sand. The optimum location of second geogrid layer was found out at the depth 0.7B from the bottom of the first layer of geogrid and increase in bearing capacity was observed to be around 280%. Optimum content of plastic strip reinforcement (1%) was mixed in the sand and sandwiched between two geogrid layers and about 450 % increase in bearing capacity was observed. Load settlement behaviour of soil indicates substantial improvement with the use of
plastic strips sandwiched between geogrid layers.
