MAINTENANCE OF CIVIL ENGINEERING STRCTURES.pptx

1. MAINTENANCE OF CIVIL ENGINEERING
STRUCTURES
PROJECT
AT
F.S. Of B.E. IV (CIVIL)
VIREN SOLANKI
DHAVAL UKANI
DILEEP LAKUM
AMIT VAGHAMSHI
Under guidance of
MR. RAJDEEP PARMAR

2. MAINTENANCE OF CIVIL
ENGINEERING
STRUCTURES

3. What is maintenance?
• The work of keeping something in proper condition, care or
upkeep including: taking steps to avoid something breaking
down and bringing something back to working order .
• Removal of any decayed or damaged part of the structure or
removal of any defect in the structure, without allowing increase
of the possible defect causing further damage to the structure.

4. OBJECTIVE
• Objective of Maintanance is to keep structures in good and
healthy conditions.
• And make some needfull improvements in the building so that it
can perform it’s function properly.
• And also provide adequate safety and convineant feel to the
people.

5. IMPORTANCE
• Improve life span of the structure
• Better appearance
• Prevent major deterioration that leads to collapse
• Ensures safety to occupants
• Ensires feeling of confidence by the user.

6. In Maintenance of building we will work on ,
• Repairing of cracks and it’s different methods
• Maintenance of beam, column and slab
• Maintenance of foundation
• Maintenance realeted to DPC and water proofing

7. In maintenance of bridge we will work on
• Repairing, restoring and strengthening of major structural
elements
• Repair of exposed bridge supports
• Work that can be improve life of bridge

8. CRACK REPAIRING METHODS
1. EPOXY INJECTION
2. GROUTING
3. STICHING

9. EPOXY INJECTION
• It is an ecconimical method of repairing non- moving cracks in concrete
walls, slabs, columns, piers etc.
• It is capable of restoring the concrete to its pre cracked strength.
• Crack injection can be successfully performed on cracks as narrow as 0.05
mm in width with general epoxy injection resine.
• Crack with less width can be injected with epoxy or othe polymer system
having a low viscosity of 200 cps.

10. PROCEDURE
• Surface preparation is the first step in the repair of cracks in concrete.
• The area to be epoxy grouted should be made free from oil, grease, dust & all loose
& unsound materials.
• Then crack in concrete is cut open into a ‘V’ groove about 10 mm deep by
mechanical or manual method.
• loose materials are removed by using compressed air.
• The ‘V’ groove cut is fully sealed with epoxy mortar at least one day in advance
before epoxy injection.

11. PROCEDURE
• Nails are driven into the cracks at 15 cm to
50 cm intervals along the clack.
• Holes of 7 to 10 mm diameter is then
drilled along the cracks and copper or
aluminium or polythene pipe pieces of 6
to 9 mm diameter is fixed as grout nipples
arounf the nails and allowed to rest on
them.
• Epoxy formulation is injected from the
bottom most pipe. all other pipes except
the adjacent ones are blocked by wooden
plug.

12. PROCEDURE
• the injection is done using suitable nozzele
connected to air compressors or by hand operated
modified grease gun pressure of 3.5 to 7 kg/squre
cm is normally used.
• as soon as the epoxy comes out from the adjacent
open popes they are plugged and the pressure is
increased to the desired level and maintained for 2
to 3 minutes.
• the injection nozzle is then withdrawn and the
hole sealed with epoxy mortar
• this operation is repeated for the other pipes also.

13. ADVANTAGES & DISADVANTAGES
• ADVANTAGES:
• It is easy to use.
• Best work in dry crack.
• Can be applied for both interior and exterior concrete crack injection
purpose.
• it makes a concrete waterproof.
• Build a strength more than concrete.

14. ADVANTAGES & DISADVANTAGES
• DISADVANTAGES:
• It is expensive.
• It is not useful in cold weather condition.
• Can not use with fire resistance.

15. GROUTING
• In this method, mixtures of grout may contain cement and water or cement
plus sand and water, depending on the width of the crack.
• However, the water to cement ratio should be kept as low as practical to
minimize shrinkage and to maximize strength. Other admixtures or water
reducers may be used to improve the properties of the grout.
• For this treatment a manual injection gun may be used in case of small
volume crack filling and for larger volumes, a pump should be used.

16. GROUTING
• For this treatment a manual injection gun may be used in case of small
volume crack filling and for larger volumes, a pump should be used.
• The good pressure should be maintained for several minutes after the group
is filled over a surface to ensure good penetration.

17. PROCEDURE
• Cleaning the concrete along the crack.
• Installing built-up seats (grout mesh) at suitable intervals (to provide a
pressure-tight connection with the injection apparatus).
• Sealing the crack between the seats with cement paint, sealant, or grout.
• Flushing the crack to clean it and test the seal and then grouting the whole
area.

19. PROPERTY OF GROUT MATERIAL
• Grout is a flowable plastic material and should have negligible shrinkage to
fill the gap or voids and should remain stable without cracking, delamination,
or crumbling.
• There are different types of grouts used for the repair and strengthening of
concrete and masonry structural members.
• The selection of the type of grout for the particular type of concrete or
masonry repair work should be based on the compatibility of the grout with
the original material.

20. MATERIAL
• Cement slurry or mortar
• polyester epoxy
• vinyl ester
• polyurethane
• acrylic resins

21. ADVANTAGES & DISADVANTAGES
• ADVANTAGES
• This can be done on almost any ground condition.
• It does not induce vibration and can be controlled to avoid structural damage.
• Improvement in-ground structures can be measured.
• Very useful for limited space and low headroom applications.
• It can be installed adjacent to existing walls.
• Can be used to control seepage, groundwater flow, and hazardous waste materials Process
and its types.

22. CRACK REPAIRING BY STICHING
• The stiching process consist of drilling holes on both the side of crack.
• Cleaning the holes and anchoring the leg of stiching dogs that span the
crack, which either non shrink grout or an epoxy resin based bonding
system.
• The stiching dogs should be variable in length and orientation or both and be
so located.

23. CRACK REPAIRING BY STICHING
• That the tension transmitted across the crack is not applied to a straight
plane but spread over areas.
• Stiching may be used when tensile strength must be reestablished across
major cracks.
• Stiching a crack tends to stiffen the structure and the stiffening may increase
the overall structured resistraint causing the concrete to crack else where.

24. PROCEDURE
• In this method, a number of the hole
drilled along the crack surface.
• Then stitched with metallic wire.
• This metallic U-shaped wire is then
passed through holes and anchored
strongly in the holes with grout or an
epoxy-based system.

26. ADVANTEGES & DIS ADVANTAGES
• ADVANTAGES:
• Quick, simple, effective and permanent.
• The grout combination provides an excellent bond.
• Masonry remains flexible enough to accommodate natural building
movement.
• Non-disruptive structural stabilisation with no additional stress.

27. ADVANTEGES & DIS ADVANTAGES
• DIS ADVANTAGES:
• More expensive than urethanes.
• Does not work well on wet surfaces, bond strength is significantly decreased.
• If foundation is still moving, cracks can reform in epoxy and concrete

28. STRENGHTINH OF BEAM,
COLUMN & SLAB
• METHOD OF STRENGTHING
1. FIBER REINFORCEMENT POLYMER
2. CONCRETE JACKETING

29. FIBER REINFORCED POLYMER
o Fiber reinforced polymer(FRP) are also called fiber- reinforced plastic is a
composite material made up of polymer material reinforced with area.
o The fiber are usually glass, carbon or aramid.
o The objective is usually to make a component which is stronger and stiff
with low density.

30. FIBER REINFORCED POLYMER
• Fiber- reinforced plastic are best suited for any design programme that
demands weight saving, precision engineering, definite tolerance and the
simplification and operation.
• A moulded polymer product is cheaper ,faster and easier to manufacture
than a cast alluminium or steel product, and maintains similar and sometimes
better tolerances and material strengths.

31. PROCEDURE
• Before a structure is to be strengthened there are
certain steps that must be under taken:
• If the inner reinforcement has extensive corrosion
or if chlorides heavily contaminate the concrete
the corroded bars and the concrete should be
removed and replace to prevent the concrete cover
spalling.
• The composites carry high loads, therefore it is
important to good bond between the plate and
concrete is created it is require that the composite
is bonded to homogeneous concrete.

32. PROCEDURE
• The primer is quickly and easily
applied to the surface with a soft roller,
primer is used for frp bonding.
• After the surface is cleaned
strengthening work starts with
applying adhesive to the prepaired
surface with roller. and then fiber are
put in place. normally there is a proper
plastic cover on the fibers to make the
headlines easier.

33. PROCEDURE
• Before applying another layer cover
is removed.
• To protect the material from uv
rays or aesthetic performance it
should be painted

35. COST
• carbon fiber compensate sheet of 1feet*1feet = 4000 to 5000 rs/squre ft
• glass fiber composite =200 to 300 rs/kg
• Polyester resin = 200 to 400 rs/kg

36. ADVANTAGES AND DIS ADVANTAGES
• ADVANTAGES:
• light weight
• adaptable to curved surface
• application could be fast (little interference with habitual use of the
structure)

37. ADVANTAGES AND DIS ADVANTAGES
• DIS ADVANTAGES:
• brittle failure
• cost is high
• lack of experience and design codes.

38. COMPERISION BETWEEN
GLASS&CARBON FIBER
• Carbon fiber composites are 15% lighter than glass fiber.
• Fiber glass is more tougher material over carbon fiber.
• carbon fiber are very expansive to manufacture so its cost is very higher than
glass fiber.
• carbon fiber is conductive and glass fiber are non conductive.s

39. CONCRETE JACKETING
• Jacketing is process of strengthening weak rcc column.
• By using the Jacketing modification of existing structure to make them more
resistance to sesmic activity, ground motion and soil failure due to earth
quake.
• The failure of the most important structural element; i.e. columns may lead
to the total collapse of frame structure elements that convey the total vertical
loads of the building to the soil.

40. CONCRETE JACKETING
• These members can loose their
strength and stiffness due to
damages during their service life
therefore repairs or reconstruction
is necessary in case of noticeable
cracks.

41. PROCEDURE OF CONCRETE
JACKETING
• It can be employed as a repair or
strengthening scheme.
• First prepair the surface of existing
structural member.
• provide shear key and reinforcement
around the existing column.
• bonding agent is applied over prepared
surface of existing column and
concrete is casted.

42. PROCEDURE
• SHEAR KEY:
• Drill holes of specified diameter and
depth to receive shear key.
• clean the drilled hole by blowing air.
• Inject epoxy bonding paste in drilled holes
to fill it from ends to half of the holes.
• Insert L shaped shear key and allow epoxy
to cure.

43. PROCEDURE
• FUNCTION OF SHEAR KEY:
• Bond properly new concrete and old concrete.
• It holds the main reinforcement in position.
• Treat a monolithic column.
• Whole section is effective.
• Improve shear resistance.
• Reduce the sliding effect between new and hollow column.

44. PROCEDURE
• REINFORCEMENT:
• The longitudinal and transerve
reimforcement as per design are
fixed around the existing column.
• reinforcement is properly tied with
shear key using binding wire.

45. ADVANTAGES
• It increases the sesmic capacity of column.
• Amount of work is less as foundation strengthening does not required.
• It increases the shear strength of column.
• It also increases confinement of concrete in circular columns.
• Steel jacketing does not increase significant weigth of column and also saves
construction time(curing).

46. DIS ADVANTAGES
• The size of section are increased and the free available usable space becomes
less.
• huge dead mass is added.
• Longitudinal bars need to anchored to the foundation and should be
continuous through the slab.
• placement of ties in the beam column joint is not practically feasible.
• The speed of implementation is slow

47. MAINTANANCE OF
FOUNDATION

48. UNDER PINNING
• Underpinning is a sensitive construction
technique for strengthening an existing foundation
or placing a new foundation below the old
foundation to a deeper depth.
• In some cases situations where a failure in
foundation or footing happens unexpectedly after
the completion of whole structure (both sub and
superstructure). Under such an emergency
situation, a remedial method has to be suggested
to regain the structural stability.

49. NECESSITY OF UNDERPINNING
• The original foundation isn't strong or stable enough.
• The usage of the structure has changed.
• The properties of the soil supporting the foundation may have changed
(possibly through subsidence) or were mischaracterized during design.
• The construction of nearby structures necessitates the excavation of soil
supporting existing foundations.

50. NECESSITY OF UNDERPINNING
• To increase the depth or load capacity of existing foundations to support the
addition of another storey to the building (above or below grade).
• It is more economical, due to land price or otherwise, to work on the present
structure's foundation than to build a new one.
• Earthquake, flood, drought or other natural causes have caused the structure
to move, requiring stabilisation of foundation soils and/or footings

51. MAINTANANCE OF FOUNDATION
UNDER PINNING:-
a) Pit method
b) Pile methods
c) Jack pile underpinning
d) Needle and pile underpinning

52. PIT METHOD
• In this method, the entire length of the foundation to be underpinned is divided
into sections of 1.2 to 1.5 m lengths. One section is taken up at a time.
• First of all, a hole is made in the wall for all divided sections above the plinth level,
and needle is inserted in the hole. The needle may be made of a material of stout,
timber or steel section.
• Bearing plates are placed above the needle to support the masonry above it. The
supporting arrangement of the needle is made by crib supports (wooden blocks) on
both sides of the wall and screw jacks.

53. PIT METHOD
• After that, a foundation pit is excavated up to the required level of new
foundation. Then the new foundation is laid in the pit. When the work of
one section is over, work on next to next section is taken up, i.e., alternate
sections are underpinned in the first round, and then the remaining sections
are taken up.
• Some important precautions should be taken during the work, such as raking
shores are provided in week wall, floors are also supported.

54. PILE METHOD
• In the Pile method of underpinning, as the name suggests Piles are installed by
proper driving technique along both sides of the wall to be strengthened. The
piling technique normally used are borehole pile on under-reamed piles are used.
• After that, concrete or steel needles are penetrated through the wall and are
connected to the Pile. These needles function is as beams and is act as pile caps also.
• Pile method is suitable for clayey soils, waterlogged areas, and also in weak bearing
strata

55. JACK PILE UNDERPINNING
• This method can be used when the depth of a suitable bearing capacity
subsoil is too deep to make traditional underpinning uneconomic.
• Jack pile underpinning is quiet, vibration free and flexible since the pile depth
can be adjusted to suit subsoil conditions encountered.
• The existing foundations must be in a good condition since they will have to
span over the heads of the pile caps which are cast onto the jack pile heads
after the hydraulic jacks have been removed.

56. NEEDLE AND PILE UNDERPINNING:-
• Where the traditional or Jack pile underpinning techniques are unsuitable for
the existing Foundation condition, then the needle and pile underpinning
method can be used for the best result.
• the piles used are generally in small diameter bored piles.
• During this method, mini piles are placed on either side of the affected wall
and are connected to a steel structure which carries and supports the load of
the wall.

57. MAINTANANCE OF
BRIDGE

58. MAINTENANCE OF BRIDGE
• The maintenance of bridge means the up-keeping of the bridge components
in good and serviceable condition so as to ensure a longer life of the bridge
as envisaged at the time of its design and construction.
• Even if the bridges are well designed and properly constructed, periodic
maintenance, if needed, is very essential to keep them in good serviceable
condition. Therefore, the bridges should be regularly inspected and properly
maintained.

59. Classification of Bridge Maintenance:
• The bridge maintenance may be broadly classified into two type
• (a) Routine maintenance or annual maintenance :-
Routine maintenance is the annual maintenance done on the basis of routine
inspection.
• (b) Quarterly maintenance :-
Quarterly maintenance based on detailed inspection and shall be undertaken
once in four years.

60. TYPES OF REPAIRS
• The following types of repairs are commonly done :
• Deck treatments
• Deck asphalt replacement
• Repairing, restoring, or strengthening of major structural elements
• Retrofit of fatigue-prone steel girders
• Replacement of deteriorated bridge railing
• Repair of exposed bridge supports
• Spot painting of steel elements
• Other work that can be shown to improve the life of the bridge.

61. MAINTENANCE OF CONCRETE DECKS
Preventive maintenance
• The main preventive maintenance objective for concrete bridge decks is to
control salt and moisture penetration to prevent and/or retard corrosion of
the reinforcement. Several activities may by required to accomplish this
objective:

62. Preventive maintenance
• (1) Keep the deck clean and provide good surface drainage by keeping the
drains open.
• (2) Monitor the condition by testing for chloride penetration, delamination
and active corrosion.
• (3) Seal or overlay the surface to prevent and/or reduce salt and moisture
penetration.
• (4) Seal cracks to prevent and/or reduce corrosion of reinforcement.

63. Concrete deck sealing
• Sealing is accomplished by providing a deck with a barrier to prevent
chloride penetration of the deck.
• All of the sealer materials require penetration as the surface film is quickly
worn away by traffic abrasion.
• There are many types of sealers including silanes, siloxanes, silicone, and
polymers such as epoxies and methylmethacrylates.

64. Concrete deck sealing
• Following are the steps needed to apply a sealer to a bridge deck:
• (1) Clean the deck by sweeping, washing and/or air-blasting. Some sealers
with high film thickness may rest on the surface.
• (2) Mark off or measure areas to be covered in order to ensure the correct
rate of application.
• (3) Prepare sealer as required, remembering some materials will set by
chemical reaction so correct proportioning and thorough mixing are vital.

65. Concrete deck sealing
• (4) Apply sealer as recommended by either:
a) Spray using pump tanks or mechanical spray equipment,
b) Notched or un-notched squeegees,
c) Rollers, or
d) Distributors.

66. Concrete deck sealing
• (5) For sealers that rest on the surface, follow-up immediately with anti-skid
material (usually sand) if required.
• (6) Anticipate cure times in the method of operation, both for lane closures
and proper curing and/or deck absorption.

67. CONCRETE DECK PATCHING
• The need for deck patching is almost always caused by corrosion of the
reinforcement.
• Deck :
• patching is a temporary repair unless all the chloride contaminated concrete is
removed before the deck is patched.
• When only the spalled and delaminated concrete is removed, the corrosion process
continues and additional spalled areas will soon appear.

68. CONCRETE DECK PATCHING
• For permanent patching, a deck
survey is performed to identify the
areas of concrete removal.
Deteriorated areas and areas with
• unacceptable corrosion potentials
and/or chloride content are
identified for removal.

69. CONCRETE DECK PATCHING
Following is a procedure for concrete
patching
• Assess areas for patching using a drag chain.
Delaminated areas will have a hollow sound.
• Outline the area to be patched with lumber
crayons or spray paint.
• Usually a concrete saw is used to saw vertically for
about 20 mm (0.75 in.) around the perimeter of
the hole. Care must be taken not to cut any
reinforcing steel in the deck.

70. CONCRETE DECK PATCHING
• The area to be patched (the hole) should be cleaned thoroughly using sandblasting
or water blasting to remove any loose concrete, rust, oil, or other contaminants that
would prevent a proper bond.
• Reinforcing steel is likely to be deteriorated as a result of corrosion. If it has lost
over 20 percent of its original cross section, new steel should be added by lapping,
welding or mechanically connecting with the deteriorated bar.
• The surface of the existing concrete adjacent to the patch should be damp but free
of standing water when fresh concrete is placed in the hole. A straight board can be
used to level the patch.

71. CONCRETE DECK PATCHING
• If the restoration of traffic before rush hours, either night or day, is a requirement,
the use of quick set, hydraulic patch materials is suggested. In order to achieve fast
curing, proportioning and mixing instructions must be followed to the letter for the
material that is used. Failure to do so could result in delayed opening to traffic and a
possible weak and porous patch.
• Wet curing of the patch is preferable, except for polymer patches. This can be done
with dampened burlap kept on the patch surface until ready to open to traffic. If the
material does not give off a lot of heat, a membrane cure is satisfactory. With
quickset hydraulic material, in two hours the concrete set can be adequate for traffic
use.

72. CRACK SEALING
• Crack sealing is an important part of deck maintenance. Concrete cracks that reach
the reinforcing steel and have widths larger than 0.18 mm (0.007 in.) will allow
moisture and chlorides to reach the reinforcing steel and corrode it.
• Sealing cracks :-
• Small cracks can be sealed by some of the liquid deck sealers on the market.
• Injecting cracks :-
• It is good practice to inject larger cracks with a material such as epoxy or
polyurethane.

73. PROCEDURE
• Following is a procedure for crack injection:
• (1) Clean out the crack. Methods to clean cracks include
Vacuuming, air blasting, and water blasting.
• (2) Seal the crack surface. To do this, brush an epoxy
along the surface of the crack and allow it to harden. If
the crack is has widely spalled edges, or if injection
pressures are too high for a surface seal, saw cut the
crack first and then, seal the surface by cutting a v-groove
and filling it with mortar.
• (3) Drill port holes along the crack.
• (4) Inject the sealant through these “entry ports”.

74. CRACK SEALING
• Important things to remember in crack
sealing are:
• • The cause of the cracking should be
addressed as part of the solution.
• • Before sealing, the crack surface must
be clean and dry.
• • The depth must be less than or equal
to the width of the seal.

75. CONCRETE DECK REPLACEMENT
• Most bridge maintenance crews do not attempt concrete deck replacement
because the manpower, material, and equipment requirements are more than
they can spare for the period of time required to replace a deck.
• The crew may have the skills required to do the work, but they are usually
needed for many smaller tasks rather than one major task.

76. CONCRETE DECK REPLACEMENT
• Some maintenance organizations have crews that specialize in concrete deck
replacement.
• When replacement is contemplated it is a good idea to look at possible
improvements to the structure as part of the work.
• Perhaps, with only slight modifications, the capacity of the bridge can be
increased. This may involve the addition of shear connectors or the addition
of one beam line.

77. CONCRETE DECK REPLACEMENT
• There may also be a need to improve or replace the rail
to bring it up to current standards, or it may be possible
to increase the roadway width when the deck is replaced.
• Deck replacement is usually considered a major event
that may trigger certain capacity and safety consideration.
• Bridge maintenance crews in some states also cast deck
panels in their shop during winter for use in future deck
replacements.
• Precast panels for a composite deck. This can be an
efficient way of replacing a concrete deck when
construction time and disruption to traffic is critical.

78. CONCRETE RAILING
• The need to repair or replace a concrete railing can be caused by:
• collision damage,
• deterioration such as cracks and spalls especially at metal railing connections
• corrosion of exposed electrical conduits at expansion joints.

79. CONCRETE RAILING
• CONCRETE RAIL
MAINTENANCE:
• Concrete rail is as susceptible to cracks
and spalls from salt damage as the deck. It
is important to protect the surface and seal
cracks. The same methods of crack sealing
can be used on the rail as on the deck.
Since the rail does not receive the same
traffic wear as the deck there are more
options for protective coatings.

80. CONCRETE RAILING
• CONCRETE RAIL REPAIR :
• For small areas of damage a patch may be
adequate. If one or more sections of rail are
broken, the procedure for concrete rail repair
includes the following steps:-
• Assuming that the rail will be replaced which is a
decision that should be made by the bridge
engineer, the plans should be obtained for use in
constructing the new sections.
• Remove concrete in sections of rail to be replaced
using jackhammer and saw.

81. CONCRETE RAILING
• Straighten or position existing steel as needed for the replacement section.
• Splice and replace reinforcing steel as needed.
• Form new sections to conform to rail dimensions on plans.
• Place concrete
• Cure concrete for at least 72 hours.
• Finish surface with a rubbing stone to match existing rail and clean up the job site.

82. STRENGTHENING OF MAJOR
STRUCTURAL ELEMENTS
• Concrete jacketing :-
• Concrete jacketing is needed to
increase bearing load capacity of the
structural design or to restore
structural design integrity due to a
failure in structural member.
• This technique is used on vertical
surfaces such as columns of bridge
and other combinations such as beam
sides, bottoms of bridge

83. STRENGTHENING OF MAJOR
STRUCTURAL ELEMENTS
• FIBER REINFORCE POLYMER:-
• A Fiber Reinforced Polymer (FRP)
typically consists of high tensile
continuous fibers oriented in a desired
direction in a specialty resin matrix.
• FRP can enhance shear, flexural,
compression capacity and ductility of the
deficient member it is quick ,neat effective
technique to repair prestressed concrete.