Abstract:
The use of Mechanically Stabilized Earth Systems is becoming increasingly popular owing to simple construction techniques along with saving in cost and time. Geosynthetic materials such as HDPE strips and grids have replaced the conventional ribbed steel strips used to reinforce the earth mass. Since HDPE materials are not being produced by the local industry, their import offsets the essential benefits of low cost and quick construction. The present study investigates the use of alternate materials including steel wire and nylon rope mesh to compare their performance with HDPE geosynthetic strips.
A total of 36 pullout tests were conducted using four different reinforcing materials. (a) Nylon Rope Mesh with 100mm grid. (b) Ribbed Steel Wire Mesh with 100mm grid. (c) Hexagonal Steel wire mesh. (d) HDPE Strips. A customized box measuring 1.52m x 0.9m x 0.9m was fabricated and samples were prepared using backfill materials in accordance with AASHTO/FHWA specifications. All materials were tested under normal pressures of 4kPa, 6kPa and 8kPa. Test results demonstrated Nylon rope mesh to be most efficient reinforcement material followed by HDPE strip. Numerical modelling using Plaxis 2D, carried out to predict the performance of MSE walls of different heights, also validated the results of experimental study.
The study concludes that locally available different reinforcing materials can be effectively used as soil reinforcement and achieve the desired performance at a much lower cost. A trial embankment in the field is also recommended to monitor actual field performance.
