Jordan Journal of Civil Engineering

Field Plate Load Test to Investigate Stress Distribution in Soil Mass with and without Reinforcement - United Arab Emirates

Authors:

Maher Omar;

Abstract:

Strengthening of geogrid reinforcement of weaker soil for foundations is an established method for improving the bearing capacity and load-settlement characteristics of the soil. Plate load tests were performed in outdoor test pits excavated in natural ground to a depth of 3B measuring 2 m x 2 m x 1.30 m using a 0.45 m diameter steel plate of 25 mm thickness. The objective of this study is to investigate the effect of geogrid layers in improving the bearing capacity of foundations and decreasing the load transferred to sub-soil layers. Earth pressure cells were used to measure directly the vertical and horizontal stresses at different depths. Results affirmed that the application of geogrid reinforcement could redistribute the applied footing load to a more uniform pattern, hence reducing the stress concentration, which consequently will result in reduced settlement. In addition, the results of model tests indicated that Boussineq model leads to an overestimation of the vertical stresses near the line of action of the load. Furthemore, using one layer of geogrid reinforcement contributes to decreasing the maximum horizontal stress by about 3%-75% at depths 0 - 1B. The maximum effect of geogrid is obtained at a depth of 2/3 B. This decrease becomes even smaller when two or three layers of geogrid are used.

Keywords:

Plate load test, Geogrid, Sand, Improvement, Stresses, Ground, Reinforcement