GEOGRID, REINFORCED WALL
GROUP 6
DANCIL, APRIL JOY B.
FABIAN, LEI CHRISTIAN
LLENA, JAY-R B.
BSCE – 5C
Geogrids - is a geosynthetic materials used as reinforcement in construction works. It can be used in the
soil reinforcement or used in the reinforcement of retaining walls and even many applications of the
material are on its way to being flourished.
Functions and Working of Geogrids
The geogrids serve the function of holding or capturing the aggregates together. This method of
interlocking the aggregates would help in an earthwork that is stabilized mechanically. The apertures in
geogrids help in interlocking the aggregates or the soil that are placed over them.
The geogrids helps in redistribution of load over a wider area. This function has made the
pavement construction more stabilized and strong.
Functional Mechanisms when applied for pavement construction :
Tension Membrane Effect
This mechanism is based on the concept of vertical stress distribution. This
vertical stress is from the deformed shape of the membrane as shown in the figure below.
This mechanism was initially considered as the primary mechanism. But later studies
proved the lateral restraining mechanism is the major criteria that must be taken into
consideration.
Improvement of Bearing Capacity
One of the main mechanism happening after Geogrid installation in pavement is
the reduction in lateral movement of the aggregate. This would result in the elimination
of stresses; that if exists would have moved to the subgrade.
The Geogrid layer possesses sufficient frictional resistance that opposes subgrade
lateral movement. This mechanism hence improves the bearing capacity of the layer.
Reduction of outward stresses means inward stresses are formed, which is the reason
behind the increase in bearing capacity.
Lateral Restraining Capability
The stresses produced by means of the wheel loadings coming over the pavement results
in the lateral movement of the aggregates. Which in turn affects the stability of the whole
pavement arrangement. The Geogrid act a restraint against this lateral movement.
Types of Geogrids
Based on which direction the stretching is done during manufacture, geogrids are classified as
1. Uniaxial geogrids
2. Biaxial Geogrids
Uniaxial Geogrids
These geogrids are formed by the stretching of ribs in the longitudinal direction. So, in
this case, the material possesses high tensile strength in the longitudinal direction than on the
transverse direction.
Biaxial Geogrids
Here during the punching of polymer sheets, the stretching is done in both directions.
Hence the function of tensile strength is equally given to both transverse and longitudinal
direction.
Applications of Geogrids in Construction
Applications of Geogrids in Construction of Retaining Walls
The usage of geogrids in retaining wall construction is in the area of soil backfills.
Holding the soil together will help in a stable retaining wall construction. The soil
structural integrity can be increased by reinforcing it by geogrids. This help in confining
backfill as well as help in distributing the loads. The geogrids solve the problems with
soft backfill or sloping ground.
Characteristics of Geogrid Retaining Wall System:
The geogrid system is more flexible in nature. The retaining wall with the geogrid
system has the higher adapting ability with the deformation of the foundation, when
compared with traditional construction, which is very stiffer in nature.
More flexibility implies they behave well as earthquake resistant
This construction can be made more economical, compared to traditional method.
The landfill can be made steeper, which shows a cost reduction. More height in wall
and steepness are created with the help of reinforced soil system.
The onboard Geogrid arrangement has afforestation protection. This brings
environmental benefits, which is an important parameter in sustainable construction.
The Geogrid retaining wall construction guaranty quality and reduced cost of
construction. This helps in rapid and convenient construction.
With time the geogrid reinforcing retaining wall construction and its advantages have
earned appreciation, which had made its demand to increase in the construction in
highways, railways, dams, ports, planning city and projects focusing on the
environment.
Applications of Geogrids in Foundation Soil
Geogrids can be used to stabilize the soil below the foundation mainly in shallow
foundation. To know that the modes of failure under the reinforced soil foundation has to be
understood.
Four failures are observed to occur:
Failure 1: Bearing Capacity Failure
Failure 2: Pullout Failure of the Geogrid layer
Failure 3: Breaking of the geosynthetic layer
Failure 4: Creep Failure of the geosynthetic layer (Geogrid)
Applications of Geogrid in Pavement Construction
The Geogrid construction in pavement construction have following features:
Improvement of subgrade: The subgrade, which is the most important load bearing
strata, is made solid and strong by the geogrids. The problem of soft subgrade can be
solved by this method.
Reinforcement of pavement base: The thickness of base if increased would increase the
stiffness of base. But increasing thickness enormously is not economical. The
reinforcement to a given base layer would give adequate stiffening that helps in reduction
of thickness and time of construction. This also helps in increasing the life of the
pavement.
Advantages of Geogrids in Construction
Ease of Construction: he Geogrid can be installed in any weather conditions. This makes it more
demanding.
Land Optimization: This method of Geogrid installation in soils makes an unsuitable area suitable
for preparing it to meet desired properties for construction. Geogrid thus helps in proper land
utilization.
Geogrid promotes soil stabilization
A higher strength soil mass is obtained
Higher load bearing capacity
It is a good remedy to retain soil from erosion
No requirement of mortar. The material is implemented dry.
No difficulty in material availability
Geogrids are flexible in nature. They are known for their versatility.
Geogrids have high durability reducing maintenance cost. They are highly resistant against
environmental influences.
Materials are tested based on standard codes and regulations.
Reference :
https://theconstructor.org/building/geogrids-types-functions-applications-
advantages/15190/?fbclid=IwAR1miJaaGTT4pDTNPAX8_HYXhK3DiZpK776iel_6pqFqvY9ywxAcfYsTT1o
