Static Behaviour of Geo-Cell Confined with Reinforced Soft Clay Soil

Abstract

• Engineers often experience difficulties in starting any construction work on soft clay because there is no hard strata at a depth of 15 m. • The application of a Geo-cell structure provides a comparatively harder stratum at the top of the soft subgrade. • Therefore, experimental investigations have been carried out on the stability of a Geo-cell reinforced soft soil structure, to evaluate the effect of the Geo-cell.

Introduction

I. INTRODUCTION

During the last three decades geo-synthetics are being extensively used to improve the Properties of poor soil, like to increase the drainage property, to reduce the compressibility, to Improve the shear strength, etc. In order to increase the bearing capacity of soft clay, use of Geo-cell is also being extensively used and so on. Dash et al. (2003) reported that provision of Geo-cell reinforcement improves the load carrying capacity of foundation soil. Normally a geo-cell Is a three-dimensional, honey-comb like structure made of geo-synthetics interconnected by Joints. Geo-grids are normally used to make the cage and geotextiles or geo-membranes are put Inside the cage for retaining the Filling material like sand, gravel or boulder. The geo-cells may Be triangular, square, rectangular or hexagonal in plan depending upon the nature of utility. Geo-cells have been found to be useful for base reinforcement of embankments and Subgrade soil, reinforcement below shallow foundations and steep slopes and in other Applications where the soil should withstand the high tensile stresses. Flexural rigidity of the Geo-cells plays an important role in increasing the strength of soil against bending. In the Present study, effects of Geo-cell in modifying the shear strength of soft clay under static and Dynamic loading have been under taken. A series of Triaxial compression tests have been carried Out on 75 mm diameter clayey soil samples reinforced with four interconnected Geo-cell placed At different depths from the top of the sample.

Table
Table 1 - Geo-cell Insert at L/2 distance

Conclusion

In this present study an effort has been taken to enlighten the use of Geocell as a reinforcing material and physical properties with original clay soil. Based on the experimental observation in current study following conclusions can be made. 1) The induced apparent excessive strength depends on the position of the geocells from the top of the sample. It is observed that when the geocells are placed at half of the diameter /width of the loading area, maximum benefit in strength is achieved. 2) Geocell reinforced soil does not show any failure stress under unconfined condition. 3) There is a degradation of strength of soil after some loading cycles, however, the degradation is marginally less once geo-cells are inserted into the soil. 4) Lesser damping ratio and higher secant shear modulus are obtained if the soil is reinforced with Geo-cell.

References

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Copyright

Copyright © 2023 Ayusman Mahaprasad Sahoo, Subash Chandra Murmu, Dipti Ranjan Patra, Sanam Sarita Tripathy. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.