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NSCET E-LEARNING
PRESENTATION
• LISTEN … LEARN… LEAD…
Department of Civil Engineering, NSCET, Theni 1
DEPARTMENT OF CIVIL ENGINEERING
• Ms.G.SUGILA DEVI.,M.E.,F.I.V.,MISTE.,
• Assistant.Professor
• Nadar Saraswathi College of Engineering & Technology,
• Vadapudupatti, Annanji (po), Theni – 625531.
SUBJECT CODE :CE6021
SUBJECT NAME :REPAIR AND REHABILITATIONS OF STRUCTURES
IVth YEAR / VIIIth SEMESTER
PHOTO
Department of Civil Engineering, NSCET, Theni 2
UNIT V
REPAIR, REHABILITATION AND RETROFITTING OF STRUCTURES
❑ STRENGTHENING OF STRUCTURAL ELEMENTS
❑ REPAIR OF STRUCTURES DISTRESSED DUE TO CORROSION
❑ FIRE
❑ LEAKAGE
❑ EARTHQUAKE
❑ DEMOLITION TECHNIQUES
❑ ENGINEERED DEMOLITION METHODS
❑ CASE STUDIES.
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❑STRENGTHENING OF STRUCTURAL ELEMENTS
Department of Civil Engineering, NSCET, Theni 4
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• Enlargement: Enlargement is the placement of additional concrete and reinforcing steel on an existing
structural member. Beams, slabs, columns, and walls, if necessary, can be enlarged to add stiffness or
load- carrying capacity.
• Example: Jacketing
•
• Composite Construction: Composite construction is a method wherein materials other than concrete are
placed in concert with an existing concrete member to add stiffness or load carrying capacity. Steel is the
most common material used in this technique. Steel plates and structural shapes can be fabricated to meet
almost any configuration requirement. Load transfer in the composite member is accomplished by the use
of adhesives, grouts, and mechanical anchorage systems.
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Post-Tensioning: Post-tensioning is a technique used to prestress reinforced concrete. The tensioning
provides the member with an immediate and active load-carrying capability. Placement of the tension
components can be achieved either internally within the member or externally to the member.
Tension components are generally steel plates, rods, tendons or strands. Tension is imparted to the
components by jacking or, less commonly, by preheating. Post-tensioning enhances a member's
ability to relieve overstressed conditions in tension, shear, bending, and torsion. The post-tensioning
technique can also be used to eliminate unwanted displacements in members and to turn
discontinuous members into continuous members.
Department of Civil Engineering, NSCET, Theni
• Stress Reduction: Stress reduction is a technique that reduces stress in a member or structure. Some of the more common methods of stress reduction include cutting new expansion joints, jacking displaced structures, and installing isolation bearings. Other more radical techniques involve the removal of portions of structures.
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Internal Grouting: Internal grouting is the placement of a flowable material into an unwanted
discontinuity, such as a crack within the concrete member. The flowable material, upon reaching the
discontinuity, will solidify and assume necessary structural properties. Internal grouting is used to
repair fractured, honeycombed, or voided concrete placements. The most common materials used for
internal grouting are polymers and hydraulic cement-based materials.
Department of Civil Engineering, NSCET, Theni
• External Grouting: External grouting is the placement of a pumpable material outside the struc- ture, generally within the surrounding foundation soils or at the interface between the structure and the soil. The grouting materials can be used either to provide necessary load transfer between the structure and soil, or to displace unwanted settlement. Most materials used for external grouting include cement-based mixtures. Pavement subsealing (slab stabilization) is a specialized external grouting technique used to fill small voids beneath the slab and/or stabilized base that have been caused by pumping action.
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• Beam Shear Strengthening•
• Beam shear capacity can be increased by using various strengthening techniques, including:•
• external post-tensioning•
• internal post-tensioning•
• internal mild steel reinforcement•
• bonded steel members•
• enlarging member's cross-section
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• Internally Placed Passive Shear Strengthening
• Strengthening of existing members to increase their shear capacity can be performed by adding shear
reinforcement. For example, the use of mild reinforcement dowels inserted perpendicular to the direction
of shear cracking, into drilled holes. The dowels are then grouted into place with epoxy.
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Beam Shear Capacity Strengthening at Moving Hinge
If a significant thermal gradient exists, in combination with insufficient tensile capacity in the bottom of the member, a
hinge may form. Hinges may occur randomly in newly formed cracks, or may form in construction joints near the
columns. Hinges open and close with daily temperature changes.
Cracks can be a cause for structural concern, since they sometimes identify insufficient shear capacity. When
strengthening the member by repairing cracks, consideration must be given to the need for providing movement of the
hinge. Generally any repair of a moving crack by bonding it with epoxy will fail.
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An effective method: the installation demonstrates how to strengthen a cracked beam with a post-tensioned shear clamp and a teflon slide bearing allowing for hinge movement
Department of Civil Engineering, NSCET, Theni
• Shear Transfer Strengthening between members•• Dowel Shear Device
• Drilled Hole Shear Transfer Device
• Grouted Subgrade
• Cantilever Shear Arm
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Fig. Dowel Shear Device
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Fig. Drilled Hole Shear Transfer Device
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Fig. Grouted Subgrade
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Cantilevered Shear Arm
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STRESS REDUCTION TECHNIQUES
Installing New Expansion Joint: Overstressing in members and structures can be repaired utilizing stress
reduction techniques. Stress can be reduced by either reducing the load applied to the structure, or by modifying
the behaviour of the structure.
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Lateral Ground Movement Isolation (Seismic Isolation)
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COLUMN STRENGTHENING
• Compressive Strengthening by Enlargement (Jacketing)
• Shear Capacity Strengthening using Shear Collars
• Beam-column Moment Capacity Strengthening
• Confinement Strengthening
Jacketing: Section Enlargement
Enlarging the cross section of an existing column will strengthen the column by increasing its load
carrying capacity. This is called Jacketing.
Department of Civil Engineering, NSCET, Theni
❑FIRE
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FIRES AS A CAUSE OF CONCRETE DETERIORATION
1
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Presentation outline• Introduction to the subject
• What is the causes of fire?
• Physical and chemical response to fire
• Spalling of concrete
• Factors influencing the explosive spalling
• How to improve the concrete structures in the fire resistance?
• Case study - Concrete structure subjected to a fire in U.A.E
• Rehabilitation methods and the repairing plan
• Recommendation and conclusions
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Introduction to the subject
• The main causes of the concrete structures
deterioration can be classified into three
categories which are mechanical, chemical and
physical causes.
• The fires are considered as one of the physical
causes of the concrete deterioration.
Concrete Deterioration
Physical Causes
Chemical Causes
Mechanical Causes
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Introduction to the subject
• The concrete as a building material has a very good
behavior when it exposed to fire, especially when it
is compared to any others building materials like
wood and steel.
• But this is not mean that the concrete has infinite fire
resistance, in some levels of fires when the concrete
exposed to high temperature up to 900oc, significant
changes in the mechanical properties of the structural
elements like stiffness and strength will be occur.
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What is the causes of fires?
Oxygen
Combust-ible
Materials
Fire
Fire Source
Fire Triangle
• For a fire to start there are three elements should be
present, oxygen, combustible materials and a fire source.
These three elements represent what is called the fire
triangle.
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Fire Development
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Fire Development
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Physical and chemical response to fire
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Physical and chemical response to fire
• 100 to 140°C - Evaporation of the free water inside the concrete mix.
• 300°C - The cement paste will start to shrink due to water evaporation and the aggregate
will expand. This will cause which is called the spalling of concrete.
• 400 to 600°C - the calcium hydroxide in the cement paste breaks to calcium oxide and
water. The resultant water from the chemical reaction, start to evaporate. This will cause a
significant reduction in the concrete strength.
• Starting from 550°C - the aggregate in the concrete will start to decompose causing
significant loss in the concrete strength.
Department of Civil Engineering, NSCET, Theni 37
Physical and chemical response to fire
• This reaction may vary based on the aggregate type and the different thermal
expansion between the cement matrix and the aggregate.
• The cooling operation after the fire, cause also physical and chemical reactions in
the concrete such as cracks, moisture absorption and rehydration of the calcium
oxide.
• All these chemical and physical reactions in both heating and cooling are
depending on the cement type, admixture, the aggregate type and the
interaction between the concrete mix materials. For example the using of
thermally stable aggregate of low thermal expansion like basalt and granite and
the using of supplementary cementitious materials like blast furnace slag, this can
improve significantly the concrete fire resistance.
Department of Civil Engineering, NSCET, Theni 38
Spalling of concrete
The spalling of concrete is the breaking and splitting of
the concrete elements surface layers due to high thermal
exposure. The spalling can be classified to three types.
A. Aggregate spalling is caused by the failure and the
splitting of the small aggregate pieces which are close
to the surface of the structural elements.
B. Corner & surface spalling which is the falling of
large corner pieces of the concrete due to tensile
cracks. and this type of spalling usually happen in the
decay stage.
Department of Civil Engineering, NSCET, Theni 39
Spalling of concrete
C. Explosive spalling, the ejection of concrete pieces from
the heated surface at high temperature. Explosive
spalling is the most dangerous type of all the types of
concrete spalling and it may cause the collapse of the
building.
Generally spalling cause a reduction in the structural
elements cross section and causing higher stress in the
remaining area of concrete. For example if the spalling
happened to the concrete column, the column may collapse
due to the increasing in the compressive stresses on the
remaining concrete section or may collapse due to buckling.
Department of Civil Engineering, NSCET, Theni 40
Factors influencing the explosive spalling
1. Heating Rate, the probability of explosive
spalling to occur increasing with the
increasing of the heating rate.
2. The exposure of the element to the fire, the
more faces of structural elements are exposed
to fire, the probability of the spalling to occur
increased. For example, slabs have better
resistance than the beams this because there
is only one face of the slabs are exposed to
fire unlike beams 3 faces exposed to fire.
Department of Civil Engineering, NSCET, Theni 41
Factors influencing the explosive spalling
3. Moisture content, generally the explosive spalling occur to the concrete with moisture contents
less than 3% by weight. However, the spalling in the high strength concrete can occur in lower
moisture contents 2.3 to 3% by weight. This is because of the low porosity and permeability,
making it more difficult for the moisture to escape. This is generate higher pore pressure and
internal tensile stresses, increasing the risk of spalling.
4. Age of concrete structure, most of the research papers indicate that the probability of the
concrete spalling decrease with the increasing of the structure age. This is because when the
concrete structure age increase, the moisture content is decreasing. As a result of that significant
decrease will happened in the generated pore pressure and the internal tension stresses.
Department of Civil Engineering, NSCET, Theni 42
Factors influencing the explosive spalling
5. Aggregates type, the probability of spalling decrease when low thermal expansion aggregates
are used.
6. Aggregate size, most of research papers and the results from the experiments indicates that the
greater size of the aggregate, more likely explosive concrete spalling is to occur.
7. Cover to reinforcement, the bigger concrete cover has a higher probability for spalling. It is
founded that if the concrete cover is more than 50mm, spalling must be feared. On the other
hand, the concrete cover with thickness less than 15mm has high probability for the spalling of
the concrete cover this is because of the unsupported concrete is small.
Department of Civil Engineering, NSCET, Theni 43
How to improve the concrete structures in the fire resistance?
1. Applying all the civil defense requirements in the architecture design stage, like the
minimum corridor width and the minimum number of escaping stairs in the building.
2. Applying the standard codes requirements in the structural design stage. Like the
minimum thickness and minimum concrete cover to the steel reinforcement of the
structural elements to achieve the required time of fire resistance. The following table
shows the minimum concrete cover required to achieve the required time for the fire
resistance as per BS8110.
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FIRESA 19
How to improve the concrete structures in the fire resistance?
Fire resistance
Hour
Nominal cover - mm
Beams Floors Ribs
Simply
supported
Continuous
Simply
supported
Continuous
Simply
supported
Continuous
0.5 20 20 20 20 20 20
1.0 20 20 25 20 35 20
1.5 35 20 30 25 45 35
2.0 60 35 40 35 55 45
3.0 70 60 55 45 65 55
S A CAUSE OF4.
C0
ONCRETEDE TERIORA8
T0
ION 70 65 55 75 65
Department of Civil Engineering, NSCET, Theni 45
How to improve the concrete structures in the fire resistance?
3. Define the fire protection system which will be used in the structure with respect to
building use and cost.
Passive fire protection system
Fire rated walls
Fire rated floors
Fire rated doors
Active fire protection system
Smoke detectors
Sprinklers
Duct detectors
Fire alarms
BALANCE DESIGN
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How to improve the concrete structures in the fire resistance?
4. The improvement of the concrete mix materials.
Cement
• High alumina and a lesser pozzolanic and blast furnace slag cements have a better performance
in the fire resistance compared to the normal Portland cement.
• When the concrete is subjected to a fire, the cement paste start to shrink due to water
evaporation and dehydration. On the other hand, the particles of the aggregates expand because
of high thermal exposure. This contrary physical reactions sets up internal stresses explain why
it is recommended to use a low aggregate - cement ratio.
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How to improve the concrete structures in the fire resistance?
Aggregates
• The siliceous aggregates can cause
spalling and its performance with
fire is badly compared with the
other types. This table shows the
minimum thickness to achieve the
required fire resistance period for
different types of aggregate.
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Water
• The water content in the hardened concrete exposed to a fire is playing very important role,
this is because there is more heat required to evaporate the saturated water which will enhance
the concrete fire resistance.
Admixtures
• The using of SCM can improve the concrete density which is considered a very important
factor in the fire resistance improvement.
• The using of polypropylene fibers in the concrete mix can improve the concrete fire resistance
especially the resistance to the spalling phenomena.
49
How to improve the concrete structures in the fire resistance?
Department of Civil Engineering, NSCET, Theni 49
• The chosen building is the Torch Tower, which
is one of the tallest residential towers in Dubai.
• the tower consist 86 floors and its height is
almost 336 m.
• On 21 February, 2015 a fire started from the
floor number 50, and because of high wind
speed in that day the fire was spread rapidly in
the other floors.
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CASE STUDY CONCRETE STRUCTURES SUBJECTED TO A FIRE
50
• The smoke detectors and fire alarms started
to work immediately. And the civil defense
started to containment the fire by using all
the modern tools and techniques.
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CASE STUDY CONCRETE STRUCTURES SUBJECTED TO A FIRE
51
Rehabilitation and repairing plan of the building
A. Concrete structure assessment
❑ Visual inspection
• In this stage it is very easy to check if there is spalling in the concrete elements. As well
as, the formation of cracks due to the generate tensile stresses.
• It is possible to make an approximation assessment of the maximum temperature
reached during the fire.
Pink or red for temperatures between 300 °C and 600 °C.
Grey‐white for temperatures between 600 °C and 900 °C.
Dull or light yellow for temperatures over 900 °C.
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CASE STUDY CONCRETE STRUCTURES SUBJECTED TO A FIRE
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❑ Testing of concrete structure
• Examination of concrete compressive strength,
by using nondestructive tests like Schmidt
hammer test.
• Carrying out acoustic test to detect the
formation of internal cracks.
• Boring and extracting core samples to carry out
compression tests and carry out both
petrographic and microscopic examinations.
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CASE STUDY CONCRETE STRUCTURES SUBJECTED TO A FIRE
53
B. Repairing operation
• The first scenario is the concrete structure
defects are only in the exposed surface layers
and the steel reinforcement still without
significant defects. As well as, the tests shows
that there are no formation of internal cracks in
the concrete structure elements and the
concrete strength still sufficient. the suitable
method of repairing in this case is to clean the
defected surface, apply chemical materials for
the bonding between the old and new concrete,
then place the concrete by using shotcrete
technique.
54Department of Civil Engineering, NSCET, Theni
CASE STUDY CONCRETE STRUCTURES SUBJECTED TO A FIRE
54
B. Repairing operation
• The second scenario if the concrete damage
and defects is very deep and there is impact on
the steel reinforcement and the concrete
strength. The suitable method for the repairing
in this case in addition to the previous method
is to sticking metal plates or carbon fiber strips
to the surface of the damaged concrete for
strengthening the concrete element.
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CASE STUDY CONCRETE STRUCTURES SUBJECTED TO A FIRE
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• The third scenario
deterioration is huge
if the concrete
and the cost of
repairing is too much compared to the
demolition and construction of new
structure. In that case the recommended
solution is to demolish the structure and
construct new one.
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CASE STUDY CONCRETE STRUCTURES SUBJECTED TO A FIRE
56
• The fires is one of the major causes of the concrete structures
deterioration (Physical causes). Therefore, it is important to apply all
the requirements and specification in the design and construction
stage to improve the concrete fire resistance.
• Dubai announced that they will apply the
• project of green concrete, this is by usingenvironmentally
materials to
friendly cementitious
improve the concrete
structures sustainability and to reduce the
emission of the carbon dioxide.
57
Recommendation and conclusions
Department of Civil Engineering, NSCET, Theni 57
❑ The advantages of using green concrete;
• Increasing the concrete structure life time by almost 20 years.
• Decrease the emission of the carbon dioxide by 80%.
• Eliminate the cracks in the plastic stage of concrete.
• Produce low permeability concrete and reduce the probability of the steel reinforcement
corrosion.
• Improve the concrete fire resistance properties.
58
Recommendation and conclusions
Department of Civil Engineering, NSCET, Theni 58
Department of Civil Engineering, NSCET, Theni
❑LEAKAGE
59
Contents
3
4
5
Testing Water leakage in Building 10
- Introduction
- Objectives
- Effect of leakage
-
- Causes of leakage 19
-
- Maintenance for leakage
- Material for Damp proofing
- Conclusion
leakage in buildings and remedies 23
27
28
33
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1. IntroductionOne of the basic requirements in all buildings is that the structure should
remain dry as far as possible. If this condition is not achieved, the building may
become un habitable and unsafe from structural point of view.
The entry of water or dampness into a building is termed as leakage.
Leakage in buildings is common and it is important to understand the causes
and measures to be taken for their prevention .
Most of the building materials having pores in their structure as for example
concrete expand on absorbing moisture from atmosphere and shrink on drying.
These movements are reversible .
at condition of saturation Leakage in buildings occurs in walls, flat roof, and
parapet wall …. etc.
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2. OBJECTIVES
To upgrade Maintenance Technologies and Methodologies to achieve
improvement in productivity and performance Of our buildings by applying
Leakage Treatment .
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5
3. Effect of leakageThe structure is badly affected by dampness. The prominent effect of
dampness is as follows:
1) A damp building creates unhealthy conditions for those who occupyit
(give a rise for breeding of mosquitoes ).
2) The metals used in the construction of the building are corroded.
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3) Unsightly patches are formed on the wall surfaces and ceilings.
4) Decay of timber takes place rapidly due to dampness
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7
5) The electric fittings are deteriorated due to dampness.
6) The material used as floor coverings are
seriously damaged.
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8
7)
8)Wall decoration and paint damaged.
softening and crumbling plasters
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9- disintegration of thermistone and brick wall by dampness
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4. Testing Water leakage in Building
ASTM E2128-01a, Standard Guide for Evaluating Water Leakage of
Building Walls, published in January 2002 by ASTMInternational
This guide describes methods for determining and evaluating causes of water
leakage of exterior walls.
This guide is intended to provide building professionals with a
comprehensive methodology for evaluating water leakage through walls.
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systematic approach to an evaluation
1) Review of project documents,
2) Evaluation of the wall’s design concept,
3) Determination of the building’s service history,
4) Inspection,
5) Investigative testing,
6) Analysis, and
7) Report preparation
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Test opening at -cladwall
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Field testing of
suspect window
installation.
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ASTM spray
rack in use on
the exterior of
an aluminum
and glass
curtain wall.
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spray rack in use to test the interior side of a parapet wall.
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Leakage detection by Digital leakage correlator IR camera
Fieldinspection leakage by IR
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Our leakage
problems
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Our leakage problems
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5. Causes of leakage-Action of rainfall : If the faces of wall exposed to heavy showers of rain
are not suitably protected, they become source of leakage in a structure. Similarly
leakages from roofs also permit rainwater or drain water to enter in a structure ,
Some times leakage from drain water cause settlement by washing the soil under
foundations .
- Condensation: The moisture is deposited on the walls, ceilings etc. due to
condensation process. Adequate ventilation is essential in any property for the
wellbeing of the residents
- Water storage in building
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Miscellaneous:
i) The orientation of a building is also an important factor. The wall obtaining
less sunshine and heavy showers of rain are liable to become damp and leaky.
ii)Very flat slope of a roof may also lead to the penetration of rainwater or drain
water, which is temporally stored on the roof.
iii)The dampness also caused due to bad workmanship in construction such as
defective rain water drain and water supply pipe connections, defective joints in
the roofs, improper connection of the walls etc.
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6. leakage in buildings and remedies
- Leakage through roofs:
(i) Lack of proper slope thereby causing stagnation of water (1.25%)
Remedy: Adequate slope should be provided to prevent stagnation ofwater
With expansion joint , clogged gutters is the most common cause of
leakage, check to see if they are clean.
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(ii) Lack of proper drainage system
Remedy: Sufficient drainage pipes should be provided .
(iii) Lack of coping of walls
Remedy: coping on the top of the wall should be provided.
(iv) Poor maintenance of water pipe connections and joints
Remedy: Maintenance of water supply pipe connections and fitting shouldbe
leak proof.
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- Leakage through walls
(i) Lack of stone cladding/ waterproof and painting
(ii) Lack of chajjas over openings
(iii) Poor orientation and wind direction
Natural ventilation
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26
- Leakage from upper floor
(i)Crack in the closet and its trap or sewerage network
Remedy: It should be replaced.
(ii) Leakage from the concealed pipe joints
Remedy: It should be examined and replaced the same.
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7. Maintenance for preventing leakage
Cleaning of terraces, drains before monsoon and when chocked.
Replacement of leaky/damaged washers in fittings.
Replacement of leaky/damaged pipe line, gate valves. etc.
Replacement of leaky/damaged gasket in flanges.
Replacements of leaky/damaged joints in CI drain pipes.
Replacement of leaky/damaged MS trays under Air Handling
Units.
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8 . Material for Damp proofing Requirement (specification)
It should be impermeable or should have very low permeability.
It should have strong adhesion with substrata.
It should be sufficiently elastic due to temperature fluctuations.
It should have high resistance of cracking.
It should be resistant to ultra violet rays.
It should be breathable i.e. permit vapor transmission.
Its application should be easy.
It should be durable. Department of Civil Engineering, NSCET, Theni 86
Materials used for damp proofing
Types
a)Flexible material: Material like bitumen felts, plastic sheeting
(Polythene sheet) etc.
.
b)Semi rigid materials: Materials like mastic asphalt or
combination of materials or layers.
c) Rigid materials: Materials like first class bricks, stones, slates,
cement concrete etc.
d)Grout consisting of cement slurry and acrylic based
chemicals/polymers.
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Commonly used materials for damp proofing.
Hot bitumen: This is a flexible material and is placed on bedding of
concrete or mortar.
This material should be applied with a minimum thickness of 3 mm.
Mastic asphalt: This is semi rigid material and it forms an excellent
impervious layer for damp proofing. Good asphalt is a very durable and
completely impervious material.
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Bituminous felts : isogam This is a flexible material. It is easy to lay and isavailable in rolls of normal wall width
Metal sheets: The sheets of lead, copper and aluminum can be used as
membranes for damp proofing.
Combination of sheets and felts : A lead foil is sandwiched between asphaltor
bituminous felt. This is known as lead core and it is found to be economical,
durable and efficient.
Stones: two course of sound and dense stones as granites, slates, etc. laid incement mortar with vertical breaking joints .
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Bricks: Dense bricks, absorbing water less than 4.5 % of their weight, can be
used for damp proofing .
Mortar: The mortar to be used for bedding layers 1:3
A small quantity of lime is added to increase the workability. For plastering
work,
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9. Conclusion
1- With new construction, if no rainfall water leaks into the interior of the
structure clearly , this not enough according to ASTM we must check leak
investigations by Techniques and Instruments of Water Leakage Detection
in Buildings like sprinkler shower ,infrared (IR)
• Thermography in addition to visual inspection to determine whether water
penetration is occurred or no .
• 2- inspection must be by a Professional staff to identify the cause(s) of
leakage before repairs to prevent unnecessary and costly repairs
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Department of Civil Engineering, NSCET, Theni 98
Department of Civil Engineering, NSCET, Theni 99
Department of Civil Engineering, NSCET, Theni 100
Department of Civil Engineering, NSCET, Theni 101
Department of Civil Engineering, NSCET, Theni 102
Department of Civil Engineering, NSCET, Theni 103
Department of Civil Engineering, NSCET, Theni 104
Department of Civil Engineering, NSCET, Theni 105
Department of Civil Engineering, NSCET, Theni 106
Department of Civil Engineering, NSCET, Theni 107
Department of Civil Engineering, NSCET, Theni 108
❑ DEMOLITION OF STRUCTURES
Department of Civil Engineering, NSCET, Theni 109
Department of Civil Engineering, NSCET, Theni 110
Department of Civil Engineering, NSCET, Theni 111
Department of Civil Engineering, NSCET, Theni 112
Department of Civil Engineering, NSCET, Theni 113
Department of Civil Engineering, NSCET, Theni 114
Department of Civil Engineering, NSCET, Theni 115
Department of Civil Engineering, NSCET, Theni 116
Department of Civil Engineering, NSCET, Theni 117
Department of Civil Engineering, NSCET, Theni 118
Department of Civil Engineering, NSCET, Theni 119
Department of Civil Engineering, NSCET, Theni 120
Department of Civil Engineering, NSCET, Theni 121
Department of Civil Engineering, NSCET, Theni 122
Department of Civil Engineering, NSCET, Theni 123
Department of Civil Engineering, NSCET, Theni
E
N
124
Department of Civil Engineering, NSCET, Theni 125
Department of Civil Engineering, NSCET, Theni 126
Department of Civil Engineering, NSCET, Theni 127
Department of Civil Engineering, NSCET, Theni 128
Department of Civil Engineering, NSCET, Theni 129
Department of Civil Engineering, NSCET, Theni 130
Department of Civil Engineering, NSCET, Theni 131
Department of Civil Engineering, NSCET, Theni 132
Department of Civil Engineering, NSCET, Theni 133
Department of Civil Engineering, NSCET, Theni 134
Department of Civil Engineering, NSCET, Theni 135
Department of Civil Engineering, NSCET, Theni 136
Department of Civil Engineering, NSCET, Theni 137
Department of Civil Engineering, NSCET, Theni 138
Department of Civil Engineering, NSCET, Theni 139
Department of Civil Engineering, NSCET, Theni 140
Department of Civil Engineering, NSCET, Theni 141
Department of Civil Engineering, NSCET, Theni 142
Department of Civil Engineering, NSCET, Theni 143
Department of Civil Engineering, NSCET, Theni 144
Department of Civil Engineering, NSCET, Theni 145
Department of Civil Engineering, NSCET, Theni 146
Department of Civil Engineering, NSCET, Theni 147
Department of Civil Engineering, NSCET, Theni 148
Department of Civil Engineering, NSCET, Theni
0
n
r
g
149
Department of Civil Engineering, NSCET, Theni 150