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A Review of Geogrid Working Platform in Soft Ground in Malaysia
Analyse du comportement de plateformes renforcées par géogilles en Malaisie
Ooi T.A.
TAO Consult Sdn Bhd, Kuala Lumpur, Malaysia
Tee C.H., Chan C.B.
Mega Geoproducts And Services Sdn Bhd, Kuala Lumpur, Malaysia
Ong R.
Tensar International Ltd, Malaysia Regional Office, Petaling Jaya, Malaysia
ABSTRACT: This paper discusses the development of geogrid applications in soft ground in Malaysia. The Sungei Way trial during
1984 was conducted to assess the performance of geogrid in road pavement field trial conditions and a forerunner to the use of
geogrid in working platform on soft grounds in Malaysia. Two layer biaxial geogrids system was first used in 1987 to rehabilitate an
offshore fabrication yard in Pasir Gudang in Johor in Malaysia. Recently. geocell mattress and mechanically stabilised layer (MSL)
formed with TriAx geogrids were used in offshore fabrication yard in Vung Tau in Vietnam. Similar concept was then adopted for a
container yard in Gebeng, Kuantan in Malaysia constructed in 2011. The settlement performances of all heavy duty working platform
reinforced with biaxial and TriAx geogrids with geocells were all satisfactory.
RÉSUMÉ: Cet article présente le développement d'applications des géogrilles en terrain meuble en Malaisie. Des essais à Sungei Way
ont été effectués au cours de l’année 1984 pour évaluer la performance d’une géogrille lors de la construction d’un revêtement routier
dans des conditions in-situ. C’est le test précurseur pour l'utilisation de géogrilles en plateforme de travail sur sols mous en Malaisie.
Un système de géogrilles biaxiales à deux couches a été utilisé pour la première fois en 1987 pour réhabiliter le chantier de
fabrication offshore de Pasir Gudang à Johor en Malaisie. Récemment, un matelas geocellulaire et une couche stabilisée
mécaniquement (MSL) formée par des géogrilles TriAx ont été employés dans le chantier de fabrication offshore de Vung Tau au
Vietnam. Un concept similaire a ensuite été adopté dans un chantier de conteneurs construit à Gebeng (Kuantan, Malaisie) en 2011.
Les performances de comportement des plateformes d’ouvrages lourds renforcées par des géogrilles biaxiales et TriAx avec
géocellules ont toutes été satisfaisantes.
KEYWORDS: geogrids, working platform, soft grounds, reinforcement, road pavement, ground stabilisation.
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1. INTRODUCTION
This paper discusses the development of geogrid in soft ground
in Malaysia. The Sungei Way trial during 1984 was conducted
to assess the performance of geogrid in road pavement field trial
conditions (Ooi et al., 2004). The results of the Sungei Way trial
were verified by the more rigorous Transport Research
Laboratory (TRL) full scale laboratory trials (Chaddock, 1988).
Based on the results of the full scale trials, it was concluded that
punched and stretched biaxial geogrids (i.e., stiff biaxial
geogrids) in granular base or subbase is effective in achieving
the following results: -
a) Interaction by interlocking between the geogrid and the
granular material is mobilised with minimal deformation of
the geogrid;
b) Tensile strains and deformations in subgrade are minimised;
c) Interlock provided by the geogrids confines the granular
materials and minimises their lateral displacement; and
d) Reduction in rut depth for similar pavement life.
The trials have shown the physical form of geogrid (e.g., rib
thickness, stiffness and shape, aperture size, rigidity and
stability, junction strength and secant modulus at low strain as
subsequently reported by Webster (1992)) and its ability to
interlock effectively have major effect on performance of the
mechanically stabilised layer (i.e., soils stabilised with
geogrids). The important findings arose out of the full scale trial
on the benefits of using stiff biaxial geogrid in the road
pavement led to the construction of loading platform using
geogrid to overcome the deformation and rutting of platform
surfaces during service. In particular, the deterioration of
platform surfaces caused by ground softening as a result of
ponding of water on the platform of offshore fabrication yard
during rainfall season. In ground stabilisation, especially for
working platforms, the loading applied to the geogrid is multi-
directional. A geogrid that can offer the properties of stiff
biaxial geogrids and possess near-uniform tensile stiffness in all
radial directions would be best suited for such application.
Watts and Jenner (2008) conducted as series of large-scale
laboratory load tests to assess the effectiveness of geogrids to
stabilise granular working platforms and concluded the use of
geogrids will significantly increase the bearing capacity of
working platforms. The research also shows that triaxial geogrid
with near-uniform tensile stiffness in the radial sense (i.e.,
TriAx) outperformed the biaxial geogrid and almost doubled the
bearing capacity offered by the un-stabilised granular blanket of
similar thickness.
Apart from using multiple layer of geogrids to stabilise
granular material in working platform application, geocell
mattresses are also used in some cases. Geocell mattress is a
series of interlocking cells formed using stiff polymer geogrid
reinforcement to contain and confine granular material
providing stiff and rough foundation to an embankment that
maximises the bearing capacity of the soft soil beneath it.
Jenner et al. (1988) used the slip line fields to assess the
improvement in bearing capacity of soft ground under geocell
mattress installed at the base of an embankment. This provided
a useful analytical method of assessing the horizontal stresses in
the geogrid elements.
In Malaysia, the first loading platform using mechanically
stabilised layer (MSL) for the fabrication yard to use geogrid
was in Pasir Gudang, Johor in 1987 (Figure 1). Two layers of
stiff biaxial geogrids were used to stabilise a metre thick of
compacted quarry waste layer that form the top portion of the
loading platform. During lifting operation the crawler crane
track can exert contact pressure of up to 500 kPa (Yong et al.,
1990, Chan, 2000, Ooi et al., 2004). Many similar loading
platforms were built later. Recently, MSL has been combined
with geocell mattress for the construction of a heavy duty
