The document provides an overview of training received by the author on implant technologies under Maccaferri Environmental Solutions from June 1-25, 2017. It covers several topics including double twisted wire mesh, its uses in gabions, rockfall protection, hydraulic works, earth reinforcement, and geosynthetics. Details are given on types of meshes, dimensions, design considerations for retaining walls, rockfall prevention and protection techniques, and recommendations for mitigation system design.

1. Implant Training under maccaferri environmental solutions
pvt ltd
(1st june 2017to 25th june 2017)
Submitted by: JAYARAMAN M M.tech 1yr
REG NO (RA1612027010007) SRM UNIVERSITY
TO :

2. AGENDA
 DOUBLE TWISTED WIRE MESH
 ROCKFALL PROTECTION
 HYDRAULIC WORKS
 EARTH REINFORCEMENT
 GEOSYNTHETICS

3. Double twisted wire mesh

4. Double twisted wire mesh
 Gabions and revetmattresses produced from double twisted
metallic coated wire mesh , and metallic coated wire for lacing
wire stiffeners , and fasteners used for manufacturing,
assembling and installation of the product.
 Hexagonal shape of the mesh provides a better distribution of
the working tension along the wire that from the mesh.
 Double twist avoids spreading of the damage caused by the
accidental breaking of any wire or mesh..

5. TYPES OF DOUBLE TWISTED WIRE MESH
 GABIONS
 RENO MATTRESS
 TERRAMESH
 ROCKFALL NETTING
 GREEN TERRAMESH
 SACK GABION

6. TYPES OF DOUBLE TWISTED WIRE MESH
 Gabions – Box gabions consist of rectangular units,
fabricated from a double twist ,hexagonal mesh of soft
annealed,heavily zinc coated wire. Gabions may be divided
in to cells by fitting diaphragms which have the function of
reinforcing the structure and make assembly and erection
easier.

7. TYPES OF DOUBLE TWISTED WIRE MESH
 Renomattress : is a special form of gabion with large plan area /thickness
ratio . it is fabricated from a similar but smaller double twist hexagonal mesh
to be used to manufacture the gabions.
 Diaphragms are spaced usually at 1.00 m centers and continuous panel of
mesh forms the base.

8. TYPES OF DOUBLE TWISTED WIRE MESH
 Terramesh : is posses two functions they are its act as a rock
facing and also a reinforcing member,
Terramesh System is a modular system used to form rock faced
reinforced soil walls (also known as Mechanically Stabilised Earth) and
embankments.
terramesh system consist of panels of double twist hexagonal woven
heavy zinc & pvc coated wire mesh.
 Green terramesh : are similar to the terramesh system but these units
are provided with coirmat(geomat) to retain the fines connected to the
wire mesh. External face is provide with an additional mesh panel and
two triangular steel brackets dia 10 mm to increase the unit strength
and for an easier erection of the unit .

9. TYPES OF DOUBLE TWISTED WIRE MESH :
 Terramesh &green terramesh system :

10. TYPES OF DOUBLE TWISTED WIRE MESH :
 Sack gabion : are cylindrical baskets made of 8x10 double twisted steel
woven wire mesh. All Sack Gabions are supplied in the collapsed
form, folded and bundled. The bundles are compressed and strapped
together at the factory for easy shipping and handling.
 Maccaferri sack gabions are mainly used for river and streaming
training works .they are made up of sheet single sheet of mesh and are
supplied with steel wire spirals .

11. TYPES OF DOUBLE TWISTED WIRE MESH :
 Rock fall netting : wire mesh netting is often used to prevent rocks
and debris from falling on to roads and railways. This solution can also
help to establish the vegetation.
 Maccaferri rockfall mesh has the same characteristics as that used for
gabions and renomattresses . double twisted weaving is strong enough
to withstand the force of the falling rocks .

12. Dimension of gabions and
renomattress (

14. Retaining wall

15. Design criteria :
 EXTERNAL STABILITY:
Potential external modes of failure
considered are:
- Sliding
- Overturning
- Bearing capacity of foundation
 INTERNAL STABILITY:
Internal Stability basically considers
two failure possibilities:
- Rupture of reinforcement
- Pullout of reinforcement

16. ROCK FALL PROTECTION TECHNIQUES

17. Rockfall protection techniques :
 Rockfalls are considered as a major risks in rock cuts in highways and
railways in mountanious terrians and unstable slopes.the provision of
rockfall mitigation system ensures that either rockfall can be prevented
to certain extent or in case minimise the impact of rockfall .
 Different types of rockfall mitigation are :
1. Prevention measure (rock anchors,scaling and trimming techniques)
2. Retention measure ( surficial strengthening)
3. Protection measures (drapery system )
4. Warning measure (warning signals& fences )

18. Prevention measure
 Prevention measure : measures are taken to increase resisting force
& minimising the disturbing force causing the rockfall and prevent any
detachment and movement of rocks eg : nailing , deep anchoring ,
correcting the rock slope by trimming and benching ,reinforcing the face
etc …
1. Shear key :reinforced shear key provide support for blocks of rock up to about a
meter thick as well as zones of loose and weathered rock at the crest of the slope.
Shear keys are used where the support requires is limited by the size of the blocks
and to prevent ravelling and loosening of closely factured , weak rock.
2. Rock anchors :are used to prevent
the sliding of blocks or wedges of rock
on discontinuties dipping out of the face.
these tensioned elements used to
prevent the movement of rocks
it can be used with or without mesh .

19. ROCK ANCHORS AND BUTTRESS

20. Prevention measure :
3. Reaction wall : if tensioned rock bolts are used to support this
portion of the slope, the fractured rock may degrade and ravel from
under the reaction plates of the anchors and eventually the tension in
the bolt will be lost in these circumstances, a reinforced concrete wall
can be constructed to cover the area of the fractured rock ,and then the
holes for rock anchors can be drilled through sleeves in the wall .
finally the anchors are installed and tensioned against the face of the
wall.
4. Buttresses: where a rockfall or weathering has formed a cavity in
the slope face, it may be necessary to construct a concrete buttresses in
the cavity to prevent the further rockfalls
buttress perform two functions 1 is to retain and protect areas of weak
rock , 2 is to support the overhang.

22. Prevention measure :
 5 Drainage system : slope stability can also be
improved through the installation of drainage system ,
which most often consist of horizontal weep drains.
 Excessive pore pressure acts on the rock mass and
lowers the shear strength along any discontinuities.
 6 Trimming : failure or weathering of a rock slope
may from an overhang on the face, which could be a
hazard if it were to fail .
 so it is required to trim blast small volumes of rocks
with minimal damage to the rock behind the trim line
should be adopted.

23. Protection measure :
 An effective method of minimizing the hazard of rockfalls is to let the
falls occur and to ensure control of distance and direction in which rocks
travel .
1. Benched slopes : flat catchment areas typically constructed at regular
intervals within rockcuts .the primary purpose of these benches is to
control the degradation of the slope and rockfalls.
2.Rock fall Ditches : rockfall ditches located at the base of the slope
immediately adjacent to the travelled away.
Ditches are typically simple to construct and maintain and they are
preferred rockfall mitigation technique .
3. Drapery system : sometime referred to as a slope protection or wire
mesh ,is well proven and widely used protection measure to control
rockfalls at or near their source ..
Drapery system consist of a row of ground anchors along the top of the
installation that are connected to a horizontal support cable, from
which a woven steel fabric is suspended downto the slopes. Some of
the other protection measures are : rockfall embankment ,rockfall
barrier ,rockfall attenuators,debris flow barrier,rocksheds&tunnels.

25. Retention measure :
 Retention measure: The measure in this category will not totally nullify
or prevent the detachment and tendency to move . measure are taken to
retain the rock masses which are on the verge of movement.
 1.Mesh /nets/netting : formed by steel wire or steel slopes or multi strand
net fabricated in different shapes as a tension bearing element which is
used as facing or to cover the slopes.
 2.Surficial strengthening system : measures are provided to strengthen
the top loose surface along the rock slope .
3. Shotcrete : is a pneumatically applied , fine aggregate mortar that is
usually placed in a 50-250mm layer and is often reinforced for improved
tensile and shear strength.
 Shotcrete can be applied in a case of severely joined rock forming small
rocks and also weathered rock surfaces zones .
 Shotcrete is reinforced by means of a welded wire mesh

27. Warning measures:
 Fences and warning signals that are triggered by
falling rock are often used to protect highways and
occasionally railroads. Warning system is sucessfully
implemented by konkan railways .

28.  Fences warning signals

29. MITIGATION SYSTEM DESIGN RECOMMENTATION
Rock anchors & shear keys : Design of anchors & bolts : rock bolt use expansion shells on the
end of the shaft to connect the bolt and rock .
The holes drilled is about 100mm longer than the bolt .
Anchor capacity is depend upon the tensile strength of the
anchor element ,grout quality.
The resistance contribution fa from the anchors can be
expressed by fa=p j
Shotcrete : Mix design for the use of shotcrete shall be as per the provision
made in IS 9012-RECOMMENTED PRACTICE FOR
SHOTCRETING
Drapery system : 1.FOS= shear resistance of the system /mobilized force on the
system as per limit equilibrium model
2. Anchor capacity
3. Interface friction fw=γwswcos ßtanθ
4.Mesh weight =fwm=γwswsin ß
5. Debris load fd= .5 H2
dγdwdcosß(cotθ – cot ß)
Ditches : Slope height and angle ,ditch width depth & shape ,anticipated
block size and quantity of rockfall,should evaluvate and seen the
design chart by ritchie.
Rock fall barrier : Force of impact acting on the barrier due to the falling mass is F=
M.∆V /∆T
Energy level ,E= 0.5 MV2+ .5 Iω2
falling velocity ,height of impact .

30. HYDRAULIC TRAINING WORKS

31. River training works & erosion :
Main purpose of river training works are :
 Erosion protection
 Control of meanders
 Containment of normal flow channel
 Flood protection
Maccaferri solution for river training works
 Channel linings
 Bank protections
 Groynes
 Weirs

32. River training works
 CHANNEL LINING : longitutinal structures & revetments
 Longitutinal structures is used to define structures with
their length parallel to the river flow ,these structures are
often built on existing natural banks and they usually
extend for a considerable distance.
 BANK PROTECTION : bank stabalisation involve the
construction of the retaining structure that should not
only effect the natural filtration between the water course
and the bank, must also guarntee the required
consolidation .

33. River training works
 Gabion weirs : are three types according to the
shape of the downstream face at the centre of flow :
vertical weirs
stepped weirs
sloped weirs
Vertical weirs is simplest type and is often used to
small weirs in a system controlling a reach of stream.
Stepped weirs : only difference is dissipates a part
of energy
Sloped weirs : weirs with sloped downstream
profile are used for bed stabalisation in
river training schemes and as impermeable
structure to create storage reservoir of between
5 and 15 meters deep.

34.  Gyrones : mean a structure which protrudes in to the
river bed, with the aim of moving the flow away from
side of the river on which the gyrones are built.

35. Mechanism of earth reinforcement
 Soil has an inherently low tensile strength but a high
compressive strength.
 soil reinforcement is to absorb tensile loads or shear
stresses within the structure. In absence of the
reinforcement, structure my fail in shear or by excess
of the deformation .

36. Effect of reinforcement on a soil
element :

37. Soil reinforcing mechanism in walls
and slopes :
 steep slope in a dry cohesion less soil with a face
inclined at ‘ βs’ to the horizontal, where βs is greater
than the internal angle of shearing resistance.
 Without the benefit of soil reinforcement the slope
would collapse, however by the incorporation of
suitable soil reinforcement the slope may be rendered
stable.

39. Components of Reinforced Earth
Structure:
 Reinforced earth structure consists of three main
components shown in Fig, namely
 Reinforcing element
 Soil back fill
 Facing element

40.  The fill material for reinforced earth structures shall be
preferably cohesion less and it should have an angle of on
interface friction between the compacted fill and the reinforcing
element of not less than 30, measured in accordance with IS
13326 Part (I).
 The soil should be predominantly coarse grained; not more than
10 percent of the particles shall pass 75 micron sieve.
 The soil should have properties such that the salts in the soil
should not react chemically or electrically with the reinforcing
element in an adverse manner.
 A wide variety of fill types can be used with the grids including
crushed rock, gravel, industrial slag, pulverised fuel ash and clay
, but fill particles greater than 125 mm should be avoided.
Soil backfill for earth reinforced
retaining structure:

41. Components of earth reinforced
structure :

42. Geosynthetic:
 Geosynthetics include a variety of synthetic polymer
materials that are specially fabricated to be used in
geotechnical, geo-environmental, hydraulic and
transportation engineering applications.
 Functions
:separation,filtration,drainage,reinforcement,fluid
/gas barrier,erosion control etc..

43. Functions of geosyntheics :

44. Functions of geosynthetics :
 Drainage: The geosynthetic acts as a drain to carry fluid
flows through less permeable soils.
 For example, geotextiles are used to dissipate pore water
pressures at the base of roadway embankments. For higher
flows, geo composite drains have been developed.
Prefabricated vertical drains
 (PVDs) ( PVD are composed of a plastic core encased by
geotetextile for the purpose of expeding consolidation of
slow draing soil ) have been used to accelerate
consolidation of soft cohesive foundation soils
below embankments and preload fills.

45. Functions of geosynthetics:
 Reinforcement: The geo synthetic acts as a
reinforcement element within a soil mass or in
combination with the soil to produce a composite that
has improved strength and deformation properties
over the unreinforced soil.
 Fluid/Gas (barrier) containment: The geo
synthetic acts as a relatively impermeable barrier to
fluids or gases. For example, geo membranes,thin film
geo textile composites, geo synthetic clay liners.

46. Maccaferri geosynthetic products :
 Reinforcement : para product (geogrid) ,macgrid
mac tex( woven geotextile) .
pavement reinforcement : macgrid , mac tex( woven
geotextile)
Drainage : mac drain
separation /filtration/protection: mac tex( woven
&nonwoven geotextile ),ballast filtered mattress,mactube
(geotube).
Barrier system : mac line ( geomembrane), mac line
(clayliners)
Erosion control : mac mat ( geomats) mac web ( geocell)

47. Mac tex Mac web Paraproduct
Mac line Mac mat

48. Mac drain : Mac drain TD
 Mac drain geo composites are made from
plastic drainage core that is thermally
bonded to a geo textile on one or both sides Mac drain C
or to a water proofing layer .
they are provide one or more function : filtration drainage ,separation,
barrier protection.
Advantages : prevents the collector drain from splitting up with fine soil particles
Removes the excess water from soil
Protects the collector drain from splitting .
Mac drain W Mac drain N Macdrain M

49. Mac grid :
Macgrid T
 Macgrid are deformed or / non deformed geogrid like
polymeric material formed by intersecting ribs joined
at the junctions main function of geogrid is
stabailisation and asphalt reinforcement
 Macgrid R Macgrid AR Macgrid EG

50. SITE VISIT IN NEMILICHERRY –CHENNAI -
RETAINING WALL BRIDGE
Geosynthetic material used on the RE wall :
PARAWEB(GEOSTRIP)
NON-WOVEN GEOTEXTILE
Function of the paraweb : is act as reinforcement
element, basically soil is weak in tension strong in
compression so to enchance the soil to strong in
tension place the paraweb as tension member.
Function of nonwoven geotextile: to act as
separation & filtration

51. SOIL PROPERTIES:
 The properties of fill as well as foundation material considered in design are:
 REINFORCED &RETAINED SOIL
 Soil Type - Fly Ash
 Unit Weight - 18 kN/m3
 Angle of internal friction - 300
FOUNDATION SOIL (REPLACED FILL)
 Unit Weight - 20 kN/m3
 Angle of internal friction – 300
ParaWeb 2E+ & 2ETM
 30, 40, 50, 60, 75, 85 and 100 kN,
 Width ranges from 80 to 95 mm.
Facing panel :
• size of standard facing panel is 1.6 m height x 2m width .
 Thickness180mm
 Std panel is reinforced with HYSD bar of 8mm dia.
 Aggregate required behind the facia panel for drainage bay .

52. PICTURES TAKEN IN
NEMILICHERRY
BRIDGE SITE :
REINFORCED SOIL
RETAINING
1. TOGGLE OR ANCHOR
BAR
2. PLACING OF
PARAWEB
3. GEOTEXTILE FOR
FILTRATION PURPOSE

53. Shriram –perungalathur -Site report- Cut slope
stabalisation :
Back to the accenture in perungalathur there is rock erosion
occurs during rainy seasons so there is need of mitigation
system ..so maccaferri planned to design a cut slope
stabalisation using gabion walls with nail anchoring.
1. As per the design ,above the foundation level ,provide podium
for entire length of the wall
2. As per the design ,series of anchor rods are inserted in to a rock
for required depth and grouting around the anchor rod .
3. Non woven geotextiles are placed behind the gabion wall, in
the face of insitu stratum for the filtration purpose.
4. Maccaferri gabions mesh type 10 x12 wire dia 2.7 to
3.7mmzinc + pvc coated.

54.  As per the design proposed drains are provided at the
top & bottom,
 After placing the gabion anchor rods are tensioned
with anchor plate (epoxy bearing plate )

55. Sectional plan view of 11m cut slope stabalisation :

56. soil nailing & placing of gabions

57. Tension the anchors with anchor plate &
finished portion of gabion wall :

58. Gabion mesh and Grout machine

59. ROCK DRILLING BIT & ROCK
DRILLING MACHINE :

60. REFERENCE :
 IRC.SP 102 . DESIGN AND CONSTRUCTION OF REINFORCED SOIL WALL .
 IS 16014 MECHANICALLY WOVEN DOUBLE TWISTED HEXAGONAL WIRE MESH
GABIONS ,REVET MATTRESS AND ROCKFALL NETTING
( galvanised steel wire or galvanised steel wire with PVC coating )
• Section 2005 river training and protection work
 BS8006 -1-2010 Code of practice for strengthened/reinforced soils and other fills

61. CONCLUSION :
 Maccaferri is to research ,design and development
advanced solution for solving problems related to civil and
environmental engineering by being involved in every
phase of projects right from design, supply and execution.
 Apart from being aggressively involved in sectors of roads
and highways, airports harbors and water & waste
management .
 From these implant training, I learned more about the
applications of river training ,earth control,soil
conservation,retainingstructure ,lining of canals ,rockfall
protection …and the design approaches .

62. Thank you