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International Journal of
Advanced Structures and Geotechnical Engineering
ISSN 2319-5347, Vol
...
01, January 2015

Building cracks – causes and remedies
GRISHMA THAGUNNA
Department of Civil Engineering, Western Region Campus, Tribhuvan University, Nepal
E-mail: grishmathagunna@gmail
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So, it is important to
understand the cause and the measures to be taken for prevention
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We all dream of a house structurally safe and aesthetically beautiful but it is not so
easy
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It is not necessary
that all type of cracks require serious attention but there are some typical types of crack (active cracks) that are
structurally hazardous
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This research work briefly describes about various direct and indirect observation methods using simple as well
as sophisticated instruments to deal with such problems
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It also explains various causes of crack and their respective remedial measures
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And also, it is found that building cracks
do not cause structural problem in direct way but it facilitates the activities which ultimately cause the problem
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Due to limited
or even reduced resources for new constructions it is
necessary to use and rely on existing structures,
which in many countries are coming to age
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One of the
main sources of information in monitoring concrete
structures is crack, indicating weak zones and acting
forces
...
al
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If they are active, they show some movement
in direction, width or depth over a measured period
of time
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Some dormant cracks are of no danger,
but if left unrepaired, cracks provide channels for
moisture penetration, which can lead to future
damage
...
e
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Cracks in concrete are extremely common but often
misunderstood
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This is not always the case
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The best that a contractor can
do is to try to control the cracking
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However,
sometimes cracks happen in spite of any precautions
taken
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1-04
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Consequently, every owner should be advised by
both the designer and contractor that it is normal to
expect some amount of cracking and curling on
every project, and that such occurrence does not
necessarily reflect adversely on either the adequacy
of the floor’s design or the quality of its
construction
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On the basis of activeness cracks are of two type;
active crack and dormant crack
...

Drying shrinkage cracking (hardened concrete crack)
is commonly associated with the loss of moisture

IJASGE 040105 Copyright © 2015 BASHA RESEARCH CENTRE
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According to IS: 456 2000, the surface width of crack
should not exceed 0
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In the
members where cracking in tensile zone is harmful
either because they are exposed to moisture or in
contact of soil or ground water, an upper limit of
0
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For
particularly aggressive environment such as the
‘severe’ category, the assessed surface width of crack
should not in generally exceed 0
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Cracking in reinforced concrete structures of various
types can be divided into two main groups:
1
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Crack on wall, parapet wall, driveway are
called non-structural cracks
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Structural cracks:
Structural cracks results from incorrect design, faulty
construction or overloading and may endanger the
safety of a building
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Causes:
1
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As deterioration process in concrete begins with
penetration of various aggressive agents, low
permeability is the key to its durability
...

The permeability of the concrete is a direct function
of the porosity and interconnection of pores of the
cement paste
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Thermal movement:
Thermal movement is one of the most potent causes
of cracking in buildings
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The
thermal movement in a component depends on a
number of factors such as temperature variations,
dimensions, coefficient of thermal expansion and
some other physical properties of materials
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Thermal variations in the internal walls and
intermediate floors are not much and thus do not
cause cracking
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3
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Concrete also gives steel within it a chemical
protection
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Steel
corrosion will also not occur as long as concrete
surrounding it is alkaline in nature having a high pH
value
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Notwithstanding this, there are
large number of cases in which corrosion of
reinforcement has caused damage to concrete
structures within a few years from the time of
construction resulting in loss of mass, stiffness and
bond in concrete and therefore concrete repair
becomes inevitable as considerable loss of strength
takes place
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Moisture Movement:
The common cause of cracking in concrete is
shrinkage due to drying
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These moisture-induced volume changes
are a characteristic of concrete
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It is the combination of
shrinkage and restraint, which is usually provided by
another part of the structure or by the subgrade that
causes tensile stresses to develop
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Cracks may propagate at much lower stresses than
are required to cause crack initiation
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These
movements are cyclic in nature and are caused by
increase or decrease in inter pore pressure with
moisture changes
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Generally
heavy aggregate concrete shows less shrinkage than
light weight aggregate concrete
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Creep
Concrete when subjected to sustained loading
exhibits a gradual and slow time dependent
deformation known as creep
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04, No
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It decreases with increase in
humidity of surrounding atmosphere and age of
material at the time of loading
...

6
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The construction industry has in general fallen prey
to non-technical persons most of whom have little or
no knowledge of correct construction practices
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Or worse still, a combination of all of these
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All the way to building completion every
step must be properly supervised and controlled
without cutting corners
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 Selection of poor quality cheap materials
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 Inadequate control on various steps of
concrete production such as batching,
mixing, transporting, placing, finishing and
curing
 Inadequate quality control and supervision
causing large voids (honey combs) and
cracks resulting in leakages and ultimately
causing faster deterioration of concrete
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 Addition of excess water in concrete and
mortar mixes
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7
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It is of crucial that the designer and specifier must
first consider the environmental conditions existing
around the building site
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It is critical for the structural designer and architect to
know whether the agency proposed to carry out the
construction has the requisite skills and experience to
execute their designs
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In addition,
inadequate skills and poor experience of the
contractor, ultimately causes deterioration of the
building
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Poor Maintenance
A structure needs to be maintained after a lapse of
certain period from its construction completion
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But early
identification of probable problems and correcting
them within time is wise idea rather
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Movement due to Chemical reactions
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The alkali
silica reaction results in the formation of swelling
gel, which tends to draw water from other portions of
concrete
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10
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There have been some building collapses in our
country due to indiscriminate additions and
alterations done by interior decorators at the instance
of their clients
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Due to the requirement
to occupy more floor area, balconies are generally
enclosed and modified for different usages
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Due
to additional loading they deflect and develop cracks
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11
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Whether the home is built on a basement or
crawlspace, the over-dig is subsequently backfilled
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This
settling will cause any concrete poured atop it to
settle along with it
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Uniform settlement up to some tolerance does not
cause the problem but differential settlement is
something that results in severe crack problem
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As per the saying “Prevention is better than

International Journal of Advanced Structures and Geotechnical Engineering
ISSN 2319-5347, Vol
...
01, January 2015, pp 16-20

GRISHMA THAGUNNA

cure” we should always try to avoid such problem by
using adequate construction material and technique,
proper design, and efficient supervision
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Excessive water in the mix may contribute
to the possibility of shrinkage
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This will help to minimize the water used in
the mix
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Cementitious materials may
increase or decrease the rate of bleed water
migration to the surface
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The
subgrade should be properly compacted at
required moisture content
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This curing plan
should include steps for both initial curing
of the concrete during placement while in a
plastic state as well as after concrete has
hardened
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 There are synthetic fibers that may help
control the extent of early drying shrinkage
crack
 Construction on expansion/contraction joints
so that temperature effect can be neutralized
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Hence in
such case the cracks are required to be cured before
they cause serious problem
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The scientific method of
determining cause of cracking is:
 State problem
 Make observation:

The important points to be considered in this
step are-structural or non-structural crack
-crack details i
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orientation, location,
length, width, depth, shape, frequency, age
-crack location within a member
-environmental exposure condition
-type of member
-appearance







Form hypothesis i
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, possible cause
Depending on observations made the basic
idea of possible causes are made with the
help of expert’s opinion
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The sub surface cracks that do not show on
the surface are detected by ultrasonic wave
method, magnetic particle method, electric
potential method and using Digital Rissmess
System (DRS)
Analyze the results and iterate if necessary
Form conclusion

The various techniques to cure crack are as below:
Epoxy injection
Cracks as narrow as 0
...
(0
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The technique
generally consists of establishing entry and venting
ports at close intervals along the cracks, sealing the
crack on exposed surfaces, and injecting the epoxy
under pressure
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However, unless the cause of the
cracking has been corrected, it will probably recur
near the original crack
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Routing and sealing
Routing and sealing of cracks can be used in
conditions requiring remedial repair and where
structural repair is not necessary
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This is a common technique for crack treatment and
is relatively simple in comparison to the procedures
and the training required for epoxy injection
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However, routing and sealing can be accomplished
on vertical surfaces (with a non-sag sealant) as well
as on curved surfaces (pipes, piles and pole)
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04, No
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Stitching may be used when tensile strength
must be reestablished across major cracks
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This technique is only applicable when cracks
run in reasonable straight lines and are accessible at
one end
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A hole [typically 2
to 3 in
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Gravity Filling
Low viscosity monomers and resins can be used to
seal cracks with surface widths of 0
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08 in
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03 to 2 mm) by gravity filling
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The
lower the viscosity, the finer the cracks that can be
filled
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Wet surfaces
should be permitted to dry several days to obtain the
best crack filling
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Unbounded
overlays may be used to cover, but not necessarily
repair a slab
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 Surface treatment
 Overlays

Conclusion:
This research work concludes that though it is
impossible to guarantee against cracking yet attempts
can be made to minimize development of crack
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The potential causes of crack can be
controlled if proper consideration is given to
construction material and technique to be used
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References:
[1] Kashyzadeh, K
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, Kesheh, N
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(2012) Study
type of Cracks in construction and its
controlling
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ijetae
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S
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[3] Er
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K
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Chand
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[4] Mishra, G
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Retrived 25 July 2014
from www
...
org
[5] Fowler, D
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Paper presented at Foundation
Performance Association
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[6] Friedman, D
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2007
[7] Roberts, C
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A paper on Evaluating cracks in
buildings
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concretenetwork
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anythingconcrete
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civildigital
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04, No

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