Indian Infrastructure and Role of Geosynthetics
Transcript of Indian Infrastructure and Role of Geosynthetics
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In order to fulfill growing population, India needs to develop
quality, reliable, sustainable and resilient infrastructure,
including regional and trans-border infrastructure to
support economic development and human well-being,
with a focus on affordable and equitable access for all.
India is currently ranked 70 out of 140 countries for
infrastructure quality in the Global Competitiveness Index.
Similarly on the quality of road infrastructure (rank 48),
adoption of standards in the coming years will deliver better
results.
Sustainable road construction: current practices and future
concepts
The road sector produces the highest level of greenhouse
gas, directly, through fossil energy used in mining,
transportation, paving works...
Besides, huge challenges await the road construction sector
such as a cheaper and better production, construction and of
course maintenance, all the more as raw materials are
becoming scarce and the environmental laws are getting
stricter regarding air pollution and noise disturbances. Like
the rest of the sectors, the road construction sector needs to
face the challenge of sustainability.
Role of Geosynthetics for building Sustainable roads
Conventional construction material like aggregates is
becoming progressively scarce on account of environmental
concerns as well as legal restrictions on quarrying while the
construction activity has expanded phenomenally. This has
shifted focus from large scale use of conventional aggregates
to use of local, recycled and engineered marginal aggregates
in construction.
Geosynthetics can enhance the properties of such recycled
and engineered marginal aggregates in construction.
Enhancing performance and reducing maintenance and
thereby increasing comfort and minimizing interruptions to
smooth flow of traffic.
Use of Geosynthetics for various applications in road
pavements optimizes the total cost of project as these
materials reduce the use of natural aggregates significantly.
This in turn reduces the construction period and impact of
carbon footprint on the environment.
To summarize, with the use of geosynthetics, apart from
technical and environmental benefit the direct cost benefit
of 10% to 30% can be achieved based on the site condition
and availability of natural aggregates.
Applications of Geosynthetics for Road ConstructionImportant applications of geosynthetics in developing good
transportation infrastructure include: Ÿ Use of Biaxial Geogrids and Geotextiles for subgrade
separation and stabilization Ÿ Use of Biaxial Geogrids and Geocells for the
reinforcement/stabilization of granular base and sub-
base courses of pavements Ÿ Use of Paving fabrics, and Asphalt Interlayer Composite
in asphalt pavements Ÿ Use of Drainage Geocomposites for behind the retaining
structures & subsurface drainage of pavementsŸ Use of uniaxial Geogrids and Geostraps for
reinforcement of fills for the construction of reinforced
soil walls and steep slopes Ÿ Use of Gabions and Geocells for retaining structures and
slope protection and stabilization Ÿ Use of high strength polyester Woven Geotextiles,
Geogrids, Geocells and PVD's for ground improvement
for embankments and reclamation fills on soft ground
Use of geosynthetics in Roads and Provisions in Indian
Codes
The new IRC SP 59: 2019 emphasizes on detailed design
methodology, specifications, construction guidelines,
standard test methods, handling and storage of all the
geosynthetics for road pavement applications.
IRC 37: 2018 “Design of Flexible Pavements” also advises for
usage of Geosynthetics in cost optimization, complex site
conditions and minimization of natural aggregates.
Indian Infrastructure andRole of Geosynthetics
August - 202072CONSTRUCTION TECHNOLOGY TODAY
PAVEMENT STABILISATION WORKS IN
AMARAVATI, ANDHRA PRADESH
Project : Construction of E10, E14 and
N16 roads in AP new capital city, Amravati Client : Amravati Development Corporation Ltd.Product and Quantities : Techgrid PP Biaxial 30/30
Geogrid – 2,50,000 Sqm and
Techgeo PN 25 Non-Woven
Geotextile – 2,50,00 SqmProblem : The major challenge was to
develop a ring road on the
agr icultural f ie lds which
contain black cotton soils
having more than 200%
s we l l i n g i n d ex . S o, t h e
government is taking all
necessary measures to adopt
the global technology to
strengthen the road network
a n d m a k e t h e r o a d
infrastructure more durable.Solution proposed:
After a careful evaluation of the project requirements and site
conditions, it was decided to reinforce the pavement section with
Techgrid PP biaxial 30/30 Geogrid + Techgeo PN25 Non-Woven
Geotextile at the subgrade level.
Specific to the roads developed in the Amaravati capital region of
Andhra Pradesh, the subgrade soil is purely black cotton with high
free swell index, wherein the current solution to counter the effect
of free swell index proposed is to prepare a subgrade of 0.5m with
sand before laying the pavement layers (Base and Sub base).
Figure 3: Typical Section of Reinforced Pavement with PP Biaxial
Geogrid and Non Woven Geotextile at the subgrade level
In this scenario addition of PP biaxial geogrid will further
improve the elastic modulus of the prepared subgrade by the
mechanism of lateral restraint and tension membrane effect.
This improvement in elastic modulus will minimise the strains
developed due to high expansiveness of existing subgrade.
Considering the effect of shallow ground water table, a non-
woven geotextile layer is provided below the geogrid. The
function of Non-Woven geotextile is to act as separation layer
between the subgrade layer and the granular base and sub
base layers.
Author by :Namrata Bichewar (Design Engineer)Manish Barot (Business Development Head)TechFeb India Industries
Figure 1: Shrinkage cracks in the existing subgrade soilFigure 1: Shrinkage cracks in the existing subgrade soilFigure 1: Shrinkage cracks in the existing subgrade soil
Rolls of Techgrid PP biaxialRolls of Techgrid PP biaxialGeogrid and Techgeo Non-WovenGeogrid and Techgeo Non-WovenGeotextile ready to be laidGeotextile ready to be laid
Rolls of Techgrid PP biaxialGeogrid and Techgeo Non-WovenGeotextile ready to be laid
Unrolling of Geogrid & GeotextileUnrolling of Geogrid & Geotextileand Inspection for any wrinkles and Inspection for any wrinkles Unrolling of Geogrid & Geotextileand Inspection for any wrinkles
Geogrid Overlaps of 150mm at the side edges
Spreading and compaction ofSpreading and compaction ofGSB material on the geogridGSB material on the geogrid+ geotextile layer + geotextile layer
Spreading and compaction ofGSB material on the geogrid+ geotextile layer
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August - 2020 73 CONSTRUCTION TECHNOLOGY TODAY
Case Study