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Journal of Materials Science and Engineering B 7 (9-10) (2017) 237-245 doi: 10.17265/2161-6221/2017.9-10.005
Categorization of Faults and Failures in Concrete
Structures, Its Causes and Magnitude of Effects
Youssef Hamze
Faculty of Engineering, Lebanese University, Beirut 96, Lebanon
Abstract: The actual requirements in the practice of renovation and reconstruction need detailed analysis for the exact theory concerning the general causes and effects on the materials of construction. In addition, these causes need to be categorized and treated individually in order to be available in the literature of the theory: Pathology of materials. This work is to analyze and classify the failure caused by many recognized effects upon buildings constructed from reinforced concrete or masonry bearings systems that attribute to the mentioned scientific line in the area of renovation and reconstruction. The objects of the categorizing and analysis are the following causes: (1) interior forces; (2) exterior forces. The result of research, testing, and the new theoretical information shows a significant process in the knowledge of serviceability, durability, strength and the age of construction materials especially the concrete. Obtaining the correct information about the concrete, as material required destructive and nondestructive testing, these help in getting results to assist in the analysis of concrete failures for putting up an adequate solution for its repairs. Results obtained from the theoretical study and laboratory testing reveled significant information on concrete failures.
Key words: Failures, damaged structure, destructive and nondestructive testing, seismic wave reflection, freeze thaw cycles, alkali, silica reactivity, durability, and serviceability, pathology of materials, repairs and restoration.
1. Introduction
The submitted paper elaborated during the last
twenty years in scientific research and practical work
in the field of analysis of the faults and failures of
concrete, and the ways of their repairs, rehabilitation
or reconstruction
Based on the actual requirements of the practice in
renovation and/or reconstruction of buildings in the
world damaged due to the different causes [1], in this
paper, the author confronted the results of the
well-known theory concerning the effects of interior
and exterior forces and its influence on construction
materials, in the environmental effects, chemical
effect, physio-chemical effects, fire, earthquakes,
flooding, and war effects, and the effects of classical
weapons are blast, impact, rebound of impact, high
temperature upon concrete, and steel [2-4].
With the result of tests and research in the sphere of
Corresponding author: Youssef Hamze, Ph.D., P. eng.,
associate professor, research fields: pathology of materials and renovation, water and environment.
statically serious failures in damaged buildings, as
well as the results of my own experiment and design
activity in the field of renovation, rehabilitation and
reconstruction of these buildings.
2. Categorization of Faults and Failures of Reinforced Concrete
This work was to categorize the failures caused by
interior and exterior forces and its influence on
construction materials. These failures are defined as
follow:
(1) Faults of construction: It is low stage in danger;
faults occurred due to the non-adequate design, or
because of unsuitable materials that caused the defects
and the damage, which developed to failure, faults that
could occur as the concrete being cast, or by using
unsatisfactory and/or unsuitable materials [1, 5].
(2) Failures of construction: It is the higher stage
that is in danger (specifically in the construction)
causing defaults in the construction and these faults
are due to the following.
D DAVID PUBLISHING
Categorization of Faults and Failures in Concrete Structures, Its Causes and Magnitude of Effects
238
2.1 Interior Forces
Technology effects such as: Poor materials, poor
practice, inadequate design, aggregate with no
appropriate characteristic, cement with default
characteristic, default of water mix, mistakes in
cement production, wrong water cement ratio, curing
of concrete in very cold environmental condition,
faults due to very hot weather conditions, mistakes in
scaffolding and mistakes in reinforcement of steel,
creeping and shrinkage.
2.2 Faults Caused due to the Exterior Forces or
Effects
Environmental attack, creeping and shrinking of
concrete, chemical attack, freeze thaw cycles, alkali
silica reactivity, corrosion of reinforcing steel, aged
construction, fatigue of materials, vibration of
construction, impact, physical damage,
physio-chemical effects. Moreover, there are effects
like geotechnical instability, settlements, geological.
Failures are due to the mechanical damage, vibration,
and natural catastrophe failures: Earthquakes, fire, war,
and flood [1, 5, 6].
For concrete structure the natural weathering
process throughout its design life and after its long
time serviceability, durability, repeating stress strain
cycles, and after physical damages or environmental
effects was classified above (interior and exterior
forces) [1, 5]. Before doing any destructive and/or
non-destructive testing [7] for the damages we want to
have good results to assist our analysis for a suitable
design; in short, before starting all this process, we
present in this paper the following algorithms of
categorization of faults and failures of structural
construction that are shown in Algorithm 1.
3. Actual Problems
The problems discussed in this paper have not been
treated in a satisfactory way up to now in any
available literature (as individual materials in the
world) such as:
In any case, there are researches on the pathology of
materials since 1938 in the world.
Britain, USA, and Europe with a systematic
observation and analysis of the most frequent failures
and faults in stones, masonry, brick, reinforced
concrete and concrete structures which is an important
part generalizing the new knowledge of the mentioned
team, in the field of pathology of building is:
The categorizing of failures and faults in building
structures, from the works dealing with the problems
concerning the failures of concrete is the interior and
exterior forces and its effects on the materials as a
fatigue, in which we have a loose of its strength,
durability and serviceability.
The aim of the submitted work is to categorize and
explain the effects upon structural elements of
construction, constructed with concrete, reinforced
concrete [5, 8], stone and brick bearing systems. To
analyze the failures caused by the above-mentioned
effects, and to set out appropriate methods of
construction renovation [9, 10], the renewal of
projects, and finally to find out possible constructing
measures for a reliable project of construction
systems of constructions in the area of damaged
projects.
4. Some Results from Research and New Theoretical Information on the Concrete Failures
4.1 Test Results from Fires Effects on Concrete
The work presents an analysis of reinforced
concrete and construction failures, the influence of
subsequent fire is upon these construction systems
[3].
Graphs 1-2 show the influence of fire on reinforced
concrete for aggregate from:
(1) Limestone
(2) Basalt stone
(3) River aggregate
(4) Industrial brick
Categorization of Faults and Failures in Concrete Structures, Its Causes and Magnitude of Effects
239
Algorithm 1 Hamze algorithm for categorization of faults and failures of structural construction.
Cate
240
Graph 1 Eff
Graph 2 Re
Percentag
in CSSR to d
4.2 Results f
The resul
concrete cor
Dams, in
throughout t
on the durab
Locations
generally le
The same a
egorization of
ffects of fire on
esults from fire
ge of declinin
due to the fire
from Test for
lts of freeze—
re samples t
Canada. T
the freezing s
bility profile [
s above th
ess susceptib
applies to sub
f Faults and F
n declining stre
e effects on dec
ng strength o
e rate.
Freeze-Thaw
—thaw tests p
taken from t
The water
season seems
[6, 11].
he high wa
ble to freez
bmerged loca
Failures in Co
ength of concre
clining strength
f steels n. 11
w Cycles
performed on
he Temiscam
level varia
to have an ef
ater level w
ze-thaw dam
ations where
oncrete Struc
ete according t
h of steels acco
1523
n 12
ming
ation
ffect
were
mage.
e the
war
con
regi
wat
its
arou
win
T
sam
and
som
sho
ctures, Its Ca
to Reichel, Vla
ording to Reich
rm water bel
ncrete and pre
ion is wher
ter levels itse
highest leve
und March; t
nter months.
The results o
mples of conc
d failure indic
me cases. Th
wn low freez
uses and Ma
dimir, Prague
hel, Vladimir.
low the surfa
events freezi
e water leve
elf. In genera
els in the su
thus, it conti
of the tests i
rete did not s
cated after 1
herefore, the
ze-thaw durab
gnitude of Ef
1971 [3].
Prague 1971.
ace continua
ing. The mos
el fluctuates
al, the water l
ummer and
nuously drop
ndicate that
survive the fu
20 freeze-tha
concrete, as
bility in table
ffects
lly heats the
st susceptible
s and at the
level reaches
lowest level
ps during the
9 out of 12
ull 300 cycles
aw cycles in
s tested, has
below:
e
e
e
s
l
e
2
s,
n
s
Categorization of Faults and Failures in Concrete Structures, Its Causes and Magnitude of Effects
241
Table 1 Results from test for freeze-thaw cycles [11].
Serial No Sample reference Location of sample Cycles to failure
1 Ontario, Pier 6 3.0 m and 3.5 m 300 * Survived
2 4.2 and 4.6 m 247
3 Ontario, Pier 10 5.4 m 230
4 3.2 and 3.7 m 150
5 4.2 and 4.6 m 300 * Survived
6 5.6 and 6.0m 300 * Survived
7 6.0 and 6.5m 420
8 Quebec, Pier 3 4.8 and 5.2 m 144
9 Quebec, Pier 9 3.0 and 3.5 m 140
10 3.9 and 4.3 m 247
11 4.3 and 4.8 m 140
12 6.0 and 6.4 m 120
4.3 Results from Tests of Creeping and Shrinking
The creep strain (εc) should be a time-dependent
strain which must be equal to the sum of the delayed
strain and the delayed inelastic strain, (εc) = (εe,d) +
(εne, d).
The Russian code expresses the shrinkage by means
of coefficient in the formula of: εs = εs124, where
1 and 2 have the same meaning as for creep, εs is
the final value of shrinkage under various climatic
conditions, and 4 is a coefficient accounting for the
age of concrete (t0) [12].
4.3.1 Factors Effecting the Creeping and Shrinking
of Concrete
These factors are: effect of time and age of concrete,
ambient conditions, dimension of the structural
numbers, type of cement, type of aggregate, influence
of the state of stress and influence of modulus of
elasticity and temperature, and influence of
water/cement ratio in which we introduce some results
according to Alexandrovsky.
In this article, we choose the results of
water/cement ratio as a factor influencing creep and
shrinkage of concrete [12].
4.4 Results from Testing of Water/Cement Ratio
Affected by Shrinking and Creeping.
The water/cement ratio (w/c) has a significant effect
on the magnitude of creep and shrinkage; the effect of
w/c ratio is evident from Graph 3, which summarized
the research of several authors according to Wagner
[12]. Creep of concrete with w/c equal to 0.65 is
chosen as the reference. The functional dependence of
the ratio (εc)/(εc)0.65, on w/c is depicted by dashed
curve, so that the higher the value of w/c is, the greater
is the creep; some other results are given in Graph 4.
The relationship between the shrinkage and w/c
ratio is depicted in Graph 5 (the curves obtained from
test data).
4.5 Test Results from War, Classical Weapons Effects
The analytical test results of the classical weapon
effects upon bearing concrete and brick structures [2]
present the algorithm in Algorithm 2.
4.6 Results from Corrosion Mechanism
Corrosion usually takes place electro-chemically in
galvanic or electric cells. For these cells to become
fully active, they require the presence of an
electrolyte-water containing dissolved substances
whose ions can conduct electricity.
The water contains dissolved substances whose ions
can conduct electricity and two metallic connected
surfaces that generate different electric potentials with
respect to the electrolytes that are in contact with each
of them. This electric potential can result from two
dissimilar metals coupled in the same electrolyte or two
Cate
242
Graph 3 Eff
Graph 5 Eff
similar meta
The two
potentials c
electricity f
from one ce
and then bac
The electr
each other t
place, creati
This resul
in the isola
concrete an
steel and
reinforced c
from forces
egorization of
ffect of water/c
ffect of water c
als coupled in
metallic surf
called electr
flows throug
ell electrode (
ck through th
rodes in a cor
that they can
ng the incide
lts in a rapid
ated area an
d to losses o
concrete in
concrete. Th
more than 30
f Faults and F
cement ratio on
ement ratio on
n different ele
faces have di
rodes. Fig.
gh the elect
(anode) to the
e electrolytes
rrosion cell c
n be very ne
ence of localiz
loss in the st
nd leads to
of the cohes
the cross
his deteriorat
0 MPa [12],
Failures in Co
n creep. Graph
n shrinkage.
ectrolytes.
ifferent electr
1 shows
trical connec
e other (catho
s [1].
can be so clos
arly in the s
zed pitting.
teel cross sec
deterioration
sion between
section of
tion is resul
and under se
oncrete Struc
h 4 Effect of w
rical
that
ction
ode)
se to
same
ction
n of
n the
the
lting
evere
con
and
failu
T
pas
loca
furt
mor
dee
mig
whe
to f
cath
by t
the
ctures, Its Ca
water/cement r
nditions as in
d to oxidati
ures.
The incidenc
ses into solu
alized anode
ther negative
re iron passe
eper pit. The
grate through
ere they reac
form hydrox
hode for the e
the pit contin
localized effe
uses and Ma
ratio on magni
n areas expo
ion, hence
ce of pitting
ution as ferro
e to be set
ely charged
es into soluti
electrons ge
h the reinfo
t in the prese
xyl ions (OH
electrochemic
uing to act as
fects of corros
gnitude of Ef
itude of final s
osed to chem
this leads t
g is accelera
ous ions (Fe2
up. This an
chloride ion
on creating a
enerated by
orcement to
ence of oxyg
H-). This area
cal reaction a
s a sacrificial
sion is accele
ffects
specific creep.
mical attacks
to structural
ated as iron2+) causing a
node attracts
ns (Cl-) and
a deeper and
this reaction
other areas
en and water
a becomes a
and protected
anode. Thus,
erated.
s
l
n
a
s
d
d
n
s
r
a
d
,
Categorization of Faults and Failures in Concrete Structures, Its Causes and Magnitude of Effects
243
Algorithm 2 Algorithm of analysis of the effect of classical weapons on the structural elements in concrete and masonry structures.
Cate
244
Fig. 1 Show
The hydro
through the
ferrous ion
form iron h
These action
4.7 Results f
The alka
reaction bet
in Portland
minerals pre
the reaction
cracking in
susceptible
alkaline solu
solutions. T
catholic pro
generating h
which build
fluids. The
deterioration
of reactivity
the cement
conditions.
Results
alkali-aggreg
(1) Alkal
in this react
those conta
structures b
egorization of
w a simple galva
oxyl ions pro
e concrete po
from the an
hydroxide, wh
ns illustrated
from Alkali-A
ali-aggregate
tween the alk
cement and
esent in som
n may caus
service. Rea
aggregates an
utions, such
he studies ha
otection can
hydroxyl ion
ds up sodium
factors that
n, the expans
y of the aggreg
t and the
concluded
gate reaction
i-Silica react
tion are opal
aining more
by these ty
f Faults and F
anic cell.
oduced at the
ore water un
node. Thus, t
hich in time
in Fig. 2.
Aggregate Rea
reaction is
kalis (sodium
d certain sil
me aggregates
se abnormal
ction can als
nd external s
as seawater
ave conclude
aggravate
at the catho
m and potassi
affect the de
ion character
gates, are the
severity of
three diffe
:
tion: the agg
, vitreous vo
than 95%
ypes show
Failures in Co
Fig. 2 Illustr
e cathode dif
ntil they me
they combin
converts to
action
defined as
m and potassi
liceous rocks
s; the produc
expansion
so occur betw
sources of hi
and de-icing
ed that the us
the problem
olic steel surf
ium ions in p
egree and rat
ristics and de
e alkali conten
f the expo
erent types
gregates invo
olcanic rocks
silica. Affe
a high rate
oncrete Struc
rat the mechan
ffuse
eet a
ne to
rust.
the
ium)
s or
ct of
and
ween
ghly
salt
se of
m by
face,
pore
te of
gree
nt of
osure
of
lved
and
ected
e of
exp
effe
(2
invo
type
is u
exp
(
this
reco
con
sod
can
con
to
indi
reac
5. C
T
con
met
T
con
failu
the
reno
A
effe
in c
ctures, Its Ca
nism for pitting
pansion that u
ected structur
2) Alkali c
olved in this
es of limesto
usually chara
pansion.
3) Alkali-sili
s type reacti
ognitionare
ntaining verm
dium and pota
n lead to hig
ncrete, which
produce an
icated that
ctivity could
Conclusion
The categoriz
ncrete has a s
thod and anal
The categori
ncrete is very
ure structure
materials le
ovation.
An algorithm
ect of classic
concrete and m
uses and Ma
g corrosion cau
usually occu
re [8, 14].
carbonate re
s type of rea
one. The reac
acterized by
ca reaction: t
ion, which h
greywackes,
miculite. Po
assium comp
ghly alkaline
can react wi
expansive g
the pressure
reach up to 1
ns
zation of th
significant rol
lysis to solve
zation algor
y helpful for
in order to c
eading to the
was establish
al weapons o
masonry struc
gnitude of Ef
used by chlori
rs early in th
eaction: the
action are m
tion under la
the rapid o
the aggregate
has not rece
argillites a
ortland ceme
pounds and th
e pore fluids
ith susceptibl
gel. The lab
e developed
1 MPa.
e causes for
le in choosin
the failure.
rithm of the
engineers to
hoose the sui
e appropriate
hed for the an
on the structu
ctures.
ffects
de ions.
he life of an
e aggregates
mainly certain
aboratory test
ccurrence of
es involved in
ived general
and phyllites
ent contains
heir presence
s within the
le aggregates
boratory test
during the
r failures of
ng the correct
e failure of
o analyze the
itable test for
e methods of
nalysis of the
ural elements
n
s
n
t
f
n
l
s
s
e
e
s
t
e
f
t
f
e
r
f
e
s
Categorization of Faults and Failures in Concrete Structures, Its Causes and Magnitude of Effects
245
The water/cement ratio (w/c) has a significant effect
on the magnitude of the creep and shrinkage.
The expected life of the old concrete can be
determined by study review, plan for investigation,
analysis, evaluation, and repairs or reconstruction can
be provided for all structures exposed to
environmental effects such as freezing and thawing
(having similar weather condition).
Before proceeding with any testing, it is prudent to
carry out an assessment of the concrete faults and
failure conditions at the structural construction. This
will involve a review of the established algorithm,
interior and exterior forces, and the environmental
conditions.
After the assessment of the faults and failures of
concrete structure and using the suitable tests
materials, the correct methods of renovations are
established [13, 14].
References
[1] Meloun, V., and Tczhecoslovakie, B. 1986. “Causes of Faults and Failures on Concrete Structures and Its Study.” In Proceedings of Conferences on the Causes of Faults and Failures on Reinforced Concrete Structures.
[2] Hamze, Y., UD 1999 and Tczhecoslovakie 1988. “Analysis of Concrete and Masonry Structures Caused by War Effects and Ways of Their Renovation.” Presented at the First Syrian Lebanese Conference of Engineering.
[3] Reichel, V. 1971. “Evaluation of the Rate of Fire on the Construction.” VÚPS, Praha.
[4] Novotný, M. 1981. “Theories of Explosions.” VŠ CHT,
Pardubice. [5] Cigánek, M. 1974, “Classification, and Choose of Causes
of Failures.” In Proceedings of Conferences of “Faults and Failures of Construction and Its Maintenance and Restoration Karlovy Vary.
[6] Freeze Thaw Cycles. 1954, from concrete information printed in Canada 1954 by Portland Cement Association.
[7] Kuda, R. 1975. “Methods of Testing and Examination, Inspection and Monitoring of Failures on Construction.” Realization of Governmental Research No: C 12-333-011/5/01. Pathology of Building Construction, VUT, Brno, Tczhecoslovakie.
[8] Durable Concrete Structures—CEBDesignGuide, Second Edition. 1989.
[9] Chrobak, and Tajmir, M. 1982. “Failures and Rehabilitation of Buildings.” SVST, Bratislava.
[10] VUPS, Praha. 1987. “Methods of Repairs and Reinforcement of Concrete Structures Part A: Maintenance and Reinforcement of Reinforced Concrete Structures by Using Epoxy Coating.”
[11] Hamze, Y. 2000. “Analysis of Concrete in Dams Exposed to Freeze Thaw Cycles in Temiscaming Dams, Canada.” Presented at the Second Conference Franco-Lebanese of Material Sciences.
[12] Smerda, Z., and Kristek, V. 1988. Creep and Shrinkage of Concrete Elements and Structures. Amsterdam -Oxford-New York –Tokyo: Elsevier.
[13] Ruffert, G. “Schäden and Betonbauwerken, Köln-Braunsfeld 1982: Design and Control of Concrete Mixtures.” In Proceedings of Portland Cement Associations.
[14] Hamze. Y. 2015. Concrete and Masonry Structural Renovation. Presentations: Analysis of Faults and Failures in Concrete and Masonry Structures, Its Causes, Testing and Monitoring, Repairs and Renovation, Rehabilitation or Reconstruction.
