Emerging Trends in Ground Improvement Techniques
B.S.Asha
1
, B. Ram Rathan Lal
2
, A. H. Padade
3
, T. Mandal
4
and J. N. Mandal
5
1,2,3
Research Scholar,
5
Professor Civil Engineering Department, Indian Institute of Technology
Bombay, Powai, Mumbai 400 076, India. Email:09404802@.iitb.ac.in
4
Under Graduate Student, Civil Engineering Department, Datta Meghe College of Engineering,
Mumbai, India.
ABSTRACT
The developing countries like India are facing challenging infrastructure
projects on fine grained compressible soft foundation soils in the areas of airways,
highways and railways. Therefore it is necessary to develop new innovative ground
improvement techniques, which should be technically feasible and economically
viable for the applications in civil engineering. Therefore an attempt has been
focused in this paper to provide new techniques for ground improvement using
Natural Prefabricated Vertical Drains (NPVD) and Polymer Prefabricated Vertical
Drains (PPVD), geocell and geofoam. The flow rate with different hydraulic
gradients has been compared with NPVD and PPVD. It is observed that the flow rate
of NPVD is lower with respect to PPVD. Three dimensional geocell mattresses made
of geosynthetic material and expanded polystyrene geofoam has been used in
swelling soils. The finite element analysis has been carried out without and with
geocell system using PLAXIS 2D professional version as a tool. It has been observed
that the new system reduces settlement and improves the bearing capacity. Also
Expanded Polystyrene (EPS) geofoam has been used as a fill material in the
embankments which is an effective solution against the conventional fill material.
The slope stability analysis of embankment has been carried out with conventional
fill and EPS geofoam using PLAXIS 2D professional software. It has been observed
that there is considerable increase in the factor of safety of the embankment made up
of EPS geofoam with respect to conventional fill. Using geofoam as filling material a
significant reduction in settlement has been observed.
INTRODUCTION
With the advent of geosynthetics, the revolution of different ground
improvement systems for weak or soft soils are picking up at an unprecedented pace.
The technical viability and economic feasibility is the first priority in any upcoming
projects. The demand is increasing for the construction of different types of projects
on soft soil. In such circumstances, it is necessary to improve the ground in order to
achieve the adequate soil bearing capacity and tolerable settlements. It is difficult to
adopt some of the ground improvement systems in Indian condition in terms of
(a) availability of material (b) cost (c) time (d) cumbersomeness (e) space availability
(f) high energy consumption and (g) environmental friendliness. Keeping these
points, alternate ground improvement systems for soft soil which are suitable under
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