case study of remaining service life assessment of a cooling

Research ArticleCase Study of Remaining Service Life Assessment of a CoolingWater Intake Concrete Structure in Indonesia

M Sigit Darmawan Ridho Bayuaji N A Husin and R B Anugraha

Civil Engineering Diploma Program Institut Teknologi Sepuluh Nopember (ITS) Surabaya 60111 Indonesia

Correspondence should be addressed to M Sigit Darmawan msdarmawanceitsacid

Received 8 August 2014 Revised 10 October 2014 Accepted 10 October 2014 Published 11 November 2014

Academic Editor Andreas Kappos

Copyright copy 2014 M Sigit Darmawan et al This is an open access article distributed under the Creative Commons AttributionLicense which permits unrestricted use distribution and reproduction in any medium provided the original work is properlycited

This paper deals with the assessment of remaining service life of a cooling water intake concrete structure (CWICS) subjectedto corrosion due to chloride attacks Field and laboratory tests were performed to determine the current existing condition of thestructure Both destructive and nondestructive tests were employed to obtain the parameter needed for the assessment Based on thecurrent condition and test results structural analysis was carried out and the remaining safety factor of CWICS was determinedFrom the analysis it was found that most concrete elements of CWICS had safety factor greater than unity and might fulfil itsintended service life up to the year 2033 However fewer elements require immediate strengthening to extend their service life

1 Introduction

Corrosion of reinforcing steel due to chloride attack isconsidered to be the primary cause of concrete deteriorationof reinforced concrete structure [1] This factor combinedwith poor practice in detail design bad supervision andbad construction execution lead to early deterioration ofconcrete structures Concrete structures built 30ndash40 years agooften do not comply with the present day and more moderncode requirement for durability For example most of thepresent day concrete codes specify that the minimum coverfor concrete structures built in marine environment is 65mm[2] whereas the corresponding minimum concrete coverduring that time is around 50mm Furthermore theoreticalfoundation of chloride penetration in concrete structurewas not yet fully developed and well understood at thattime This lack of knowledge and understanding on concretedeteriorationmechanism lead to nonintended faulty concretepractices Therefore it is not surprising that older concretestructures often has durability problem before their designlife has expired

It is also expected for concrete structures built in a tropicalcountry such as Indonesia to have higher corrosion rate thanthat of concrete structures built in temperate or cold region[3] This higher corrosion rates are caused by higher average

temperature and higher humidity experience by concretestructures along the years Furthermore workmanship andconstruction practice in Indonesia is not as good as those ina developed country All of these factors may lead to earlydeterioration of concrete structures and shorten the servicelife of concrete structure

2 Case Study

This paper presents a study of remaining life assessment[4] of cooling water intake concrete structure (CWICS) atIndonesiaThe study is comprised of field and laboratory testand followed by analytical study CWICS has been in servicefor 19 to 33 years and subject to continues chloride attack fromnearby sea Therefore it almost reaches its design servicelife of 30 years In addition part of CWICS also subjects tohigh temperature from the discharge cooling water from thefactory This higher temperature can increase corrosion rateof steel rebar in concrete [5] All of these conditions mayshorten the service life of CWICS and endanger the factoryoperation CWICS has an important role in gas productionfactory as it supplies cooling sea water needed by the factory

At present some parts of CWICS have shown some signsof damages such as staining rusting cracking spalling

Hindawi Publishing CorporationAdvances in Civil EngineeringVolume 2014 Article ID 970393 16 pageshttpdxdoiorg1011552014970393

2 Advances in Civil Engineering

Figure 1 Cracking of concrete plate (slab) of CWICS

and delamination of concrete see Figure 1 These damagesindicate that the chlorides may have already penetratedconcrete cover reached rebar level and accumulated tothreshold level chloride concentration to initiate corrosionThe corrosionmay have reduced rebar cross-section and leadto a reduced strength capacity of some structural elementsof CWICS If this condition is not rectified soon it mayendanger the whole structure of CWICS and shut down thefactory operation The shutdown of the factory can lead tosignificant loss of revenue to factory owner

The purpose of this study can be summarized as follows

(i) determine current existing condition of CWICS

(ii) determine remaining life of CWICS

(a) determine the safety factor of CWICS at year2013

(b) determine the safety factor of CWICS at year2033

3 Structural Configuration of Cooling WaterIntake Concrete Structure

Cooling water intake concrete structure (CWICS) is madeof concrete structure supported by steel piles The concretestructure of CWICS comprises plate (slab) beam and wallelements A steel frame is installed on the top of CWICSfor a crane operation (see Figure 2) In addition a numberof machines for pumping sea water are stationed on top ofthe concrete structure Most of these machines run for 24hours without stopping CWICS consists of 4 trains whichhas almost similar structural configuration These are trainsAB CD EF and GH built in 1977 1982 1987 and 1995respectively These trains were built by different contractors

4 Methodology

To determine remaining service life of CWICS the currentcondition of CWICS needs to be investigated and rate ofdeterioration needs to be determined The ultimate goal ofthis study was to determine whether CWICS can fulfill itsintended service life up to 2033 without strengthening To

Figure 2 Front view of CWICS

achieve this goal the following steps and tests were employedin this study

(i) Collect information regarding design criteria fromavailable document and as-built drawing and anychanges might occur during service period

(ii) Determine current concrete density and concretecompressive strength of CWICS

(a) Compression test of core-drilled concrete sam-ple

(b) Ultrasonic pulse velocity (UPV) test(c) Hammer test(d) Porosity test

(iii) Determine carbonation depth

(a) Phenolphthalein test

(iv) Determine yield strength of rebar and remaining steelrebar thickness

(a) Tension test of rebar samples taken from core-drilled concrete samples

(b) Thickness loss measurement of corroded rebar

(v) Determine chloride content and pH of the concrete atdifferent depth

(a) Chloride content test from core-drilled concretesamples

(b) pH test

(vi) Determine chloride and sulphate contents of seawa-ter

(vii) Determine probability of corrosion of rebar

(a) Half-cell potential measurement

(viii) Structural and load modeling of CWICS using avail-able finite element program to determine the internalforces

Advances in Civil Engineering 3

(ix) Determine rate of concrete deterioration

(a) Concrete cover depth measurement

(x) Determine present capacity of structural element ofCWICS

(xi) Determine remaining service life of CWICS

At present paper only concrete structure of CWICSis considered Steel piles that supported CWICS will bediscussed in another study It must be mentioned here thatduring field tests factory operation must not be interruptedFurther safety measure in the studied area was very tight andonly limited access was given to do the field test Thereforethe number and the location of tests performed were ratherlimited To compensate this deficient data interpretation ofthe tests was combined with engineering judgment to predictremaining service life of CWICS Due to limited number ofdata obtained from this study only deterministic approachwas discussed in this paper

41 Determine Current Concrete Condition of CWICS Infor-mation regarding the design compressive concrete strengthof CWICS can be found in the available as-built drawing anddocument specification The specified concrete strength was28MPa with a maximum water-cement ratio of 04 and usedtype II cement This concrete strength is slightly lower thanthe present day minimum concrete strength requirementfor marine environment of 35MPa However the actualcompressive strength achieved during construction was notwell documented Therefore this data must be obtained byperforming field and laboratory test Four different tests wereused to estimate current concrete condition of CWICSTheseincluded compression test of core-drilled concrete samplehammer test UPV test and porosity test The most accuratemethod to determine concrete strength is compression testof core-drilled concrete sample However this destructivemethod is very expensive to perform and create permanentdefect at the existing structure (see Figure 3) Therefore thismethod was combined with nondestructive test such ashammer and UPV test to get more data for concrete strengthindication and homogeneity Hammer and UPV tests wereperformed for each location of core-drilled concrete sampleand other locations If the number of data is sufficient a corre-lation chart between these tests and compressive strength canbe derived Using this chart the concrete strength can thenbe inferred both from hammer and UPV tests However asshown later in the next section a good correlation factor wasnot always obtained between these tests due to a number ofreasons

Table 1 gives the number of concrete core-drilled samplesfor each train This table shows that more samples aretaken from older train than newer one This approach wasemployed as older train has shown more sign distress thannewer train The location of core-drilled sample at train ABis shown in Figure 4 A similar pattern of sampling was alsoused for other trains To avoid rebar in the concrete thelocation of core-drilled was first checked using rebar detectorbefore any drilling operation commenced However out of

Figure 3 Core-drilled sample

Table 1 Number of concrete core-drilled sample

Train NumbersAB 5CD 4EF 3GH 3Total 15

Table 2 Compressive strength of core-drilled sample

No Code Location Compressivestrength (kgcm2)

1 Core 1 Train AB 222132 Core 2 Train AB 246633 Core 3 Train AB 279664 Core 6 Train CD 408355 Core 8 Train CD 401706 Core 9 Train CD 377767 Core 10 Train EF 373768 Core 11 Train EF 351939 Core 12 Train EF 3976510 Core 14 Train GH 41101

fifteen core-drilled samples only ten samples were success-fully compression tested and five samples were broken duringthe drilling process The broken samples were examined andit was found that cracks were formed in these samples Thecore-drilled samples were obtained from the top of CWICS asthe access from the other sidewas very limited and the factorymust operate at all times without stopping The compressivestrength of core-drilled samples is given in Table 2

Table 2 shows that the compressive strengths of core-drilled samples of train AB are lower than the compressivestrength of core-drilled samples from the other trains Thisresult may indicate that the concrete at this oldest trainhas already experienced more strength degradation thanconcrete at the other trains The concrete strength at trainAB is lower than the present dayminimumconcrete strengthrequirement for marine environment (ie 350 kgcm2) suchas stipulates in [2] and also lower than the specified concrete


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Figure 4 Core-drilled location at train AB (Core 1C1 up to Core 5C5)

Figure 5 UPV test at train AB

strength of 280 kgcm2 as found in as-built drawing By com-parison the highest compressive strength was obtained at thenewest train GH at 41101 kgcm2 However only one core-drilled sample has been successfully tested for this train Inaddition to concrete core drill UPV and hammer tests wereperformed as shown in Figures 5 and 6The location of thesetests can be seen in Figures 7 and 8 respectively

Figure 6 Hammer test at train AB

Table 3 shows the ultrasonic velocity and its correspond-ing compressive strength for all trains This table shows thatalmost all ultrasonic velocities in the concrete fall below3000ms except the ultrasonic velocity of cores 3 and 8Based on [6] these low ultrasonic velocities can be classifiedas doubtful These low readings of ultrasonic velocity arepossibly due to discontinuity that presents in the concrete


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39984009984000 pipe drain

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Figure 7 UPV test location at train AB

plate (slab) of CWICS After a close examination of core-drilled samples in the laboratory it was found that a 20mmnonshrinking grouting material was laid on top of concreteplate to give additional protection against chloride environ-ment Because this material and the old concrete below havedifferent properties discontinuity presents between themThis discontinuity reduces the ultrasonic velocity in theconcrete The ultrasonic pulse may be diffracted around thediscontinuities therefore increasing the travel path and traveltime [7]

Table 3 indicates that core 1 drilled at train AB gives thelowest ultrasonic velocity of 1830msThis lowest value corre-sponds with its lowest compressive strength of 22213 kgcm2Similar trend is also found for train CD where low com-pressive strength corresponds with low ultrasonic velocityHowever this trend does not apply for train EF where lowcompressive strength gives high ultrasonic velocity Table 3also shows that the highest ultrasonic velocity of 3232ms isfound at core 8 with its corresponding compressive strength

of 27966 kgcm2 As each train was built in different yearsand used different concrete mixes correlation chart betweenUPV and compression strength for each train was derivedseparatelyThe correlation chart is shown in Figures 9 10 and11 for train AB CD and EF respectively

Figures 9 to 11 show that the best correlation betweenultrasonic velocity and compressive strength is found forsamples taken at train AB with a correlation factor (119877) of0997 On the contrary Figure 11 shows an opposite trendbetween these two tests at train EF where the highestultrasonic velocity gives a lower strength Again this resultconfirms that nondestructive test results should not be usedsolely without destructive test as it may lead to wronginterpretation

Figure 12 shows a correlation chart between hammerand compressive strength at train CD It gives a reasonablecorrelation factor (119877) of 072089 However if all hammer testsfor all trains are combined in one chart the correlation factorbetween hammer and compressive strength drops to 019884


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H1

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Figure 8 Hammer test location at train AB

Table 3 Compressive strength and ultrasonic velocity of core-drilled samples

Number Code Location Compressivestrength (kgcm2)

Ultrasonicvelocity (ms)

1 Core 1 Train AB 22213 18302 Core 2 Train AB 24663 23383 Core 3 Train AB 27966 32324 Core 6 Train CD 40835 24205 Core 8 Train CD 40170 30026 Core 9 Train CD 37776 24137 Core 10 Train EF 37376 18428 Core 11 Train EF 35193 22639 Core 12 Train EF 39765 200810 Core 14 Train GH 41101 2610

as shown in Figure 13 It must be mentioned herein thatbefore hammer tests were performed the hammer equipment

was calibrated first using standard anvil from the manufac-turer Further the concrete surface was first grinded to obtainflat surface However the rebound numbers obtained duringthe test were lower than those available in the literatureand also gave lower correlation factor between hammer andcompressive strength [8] One possible explanation of thiscondition to occur was that the hammer tests were performedon the top side of concrete plate As discussed earlier in thesection it was found that during the service life of CWICSa 20mm non-shrinking grouting material was laid on top ofthe concrete plate This material does not contain any coarseaggregate and therefore leads to lower rebound number ofhammer tests Hammer test performed on the other elementssuch as beam and wall elements gave a higher reboundnumber than that obtained from concrete plate elementHowever no concrete drill samples were taken from beamand wall elements as field condition did not allow the drillingprocess to be executed on these elements

Concrete porosity is the major factor that influences bothstrength and durability of concrete structure Concrete with


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1800 2000 2200 2400 2600 2800 3000 3200 3400Ultrasonic velocity (ms)

Com

pres

sion

stren

gth

(kg

cm2)

y = 14941 + 0040568x R = 099739

Figure 9 Correlation between UPV and compression strength fortrain AB

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2400 2500 2600 2700 2800 2900 3000 3100Ultrasonic velocity (ms)

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(kg

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Figure 10 Correlation between UPV and compression strength fortrain CD

high porosity has a low concrete strength and low durabilityA number of methods can be used to determine the porosityof concrete such as saturation method helium pycnometryand mercury intrusion porosimetry For this study porositytest was performed using vacuum saturation apparatus [9]The result of this test is presented in Table 4This table showsthat most of the sample has a porosity less than 10 except

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1800 1900 2000 2100 2200 2300Ultrasonic velocity (ms)

Com

pres

sion

stren

gth

(kg

cm2)

y = 50195 minus 0062572x R = 058026

Figure 11 Correlation between UPV and compression strength fortrain EF

29 30 31 32 33 34 35375

380

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410

Rebound number

Com

pres

sion

stren

gth

(kg

cm2)

y = minus13465 + 011432x R = 072089

Figure 12 Correlation between hammer and compression strengthfor train CD

for the sample taken from core 1 Core 1 has the highestporosity of 115 This value also corresponds with its lowestcompressive strength of all samples By comparison core 6has the lowest porosity at 43 but it gives only the secondhighest value of all compressive strength

Compared with the available data in the literature [1011] the porosity of concrete given in Table 4 is lower for


28 29 30 31 32 33 34 35200

250

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Rebound number

Com

pres

sion

stren

gth

(kg

cm2)

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Figure 13 Correlation between hammer and compression strengthfor all trains

Table 4 Porosity test of concrete core-drilled samples

Code Train Porosity Compressive strength(kgcm2)

Core 1 AB 115 22213Core 2 AB 78 24663Core 6 CD 43 40835Core 9 CD 98 37776Core 10 EF 83 37376Core 14 GH 84 41101

the same concrete strength The data in the literature showsthat for concrete strength of 30 to 40MPa the porosityof concrete is found around 15 to 20 On the contrarydata in Table 4 shows concrete porosity of 43ndash115 butwith corresponding max concrete strength of only 40MPaIt must be mentioned herein that all the available data inthe literatures was mostly taken at 28ndash90 days old whileporosity data presented herein was taken after 19ndash33 yearsold It appears that older concrete gives lower porosity thanyounger concrete but without significant strength gains

Figure 14 shows the correlation chart between porosityand compressive strength for all trains Compared withFigure 13 porosity has a better correlation to compressivestrength than hammer test having a correlation factor of054 This result again confirms that destructive test such asporosity test has a better accuracy than nondestructive testsuch as UPV test However porosity test requires the samplesto be taken from an existing structure and therefore it isexpensive to perform

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4 5 6 7 8 9 10 11 12Porosity ()

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pres

sion

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(kg

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y = 4969 minus 18797x R = 053944

Figure 14 Correlation between porosity and compression strengthfor all trains

Figure 15 Carbonation test of core-drilled samples

42 Determine Carbonation Depth After concrete core-drilled sample was obtained the cylinder specimen wasthen straight away tested for depth of carbonation Depth ofcarbonation was checked using a solution of phenolphthaleinindicator that appears pink in contact with alkaline concretewith pH values in excess of 9 and colourless at lower levels ofpH [12] This test is most commonly performed by sprayingthe indicator on freshly exposed surfaces of concrete brokenfrom the structure or on split cores All of the fourteensamples changed their color to pink as shown in Figure 15This showed that no concrete carbonation was detected forCWICS up to the present despite the fact that some of thetrains have been in service for more than 30 years

43 Determine Yields Strength of Rebar and Remaining SteelRebarThickness Yield strength of rebar can be obtained fromavailable as-built drawing However to get a more accuratedata of yield strength tensile test was performed Reinforcingbars extracted during concrete core-drilled were used asspecimen samples Four samples of rebar were successfully


Table 5 Corrosion thickness of rebar

Number Code Rebar diameter Train Corrosion thickness Corrosion rate (mmyear) Microstructure1 Core 3 119863 19 AB 10sim20 120583m 00003ndash00006 Pearlite and Ferrite2 Core 8 119863 19 CD 20sim50 120583m 00007ndash00017 Pearlite and Ferrite3 Core 15 119863 19 GH 3sim8mm 01875ndash05 Pearlite and Ferrite

0 5 10 15 20 250

10

20

30

40

50

60

70

80

Strain ()

Tens

ion

(KN

)

Figure 16 Force and displacement of rebar from tension test

Figure 17 Corrosion thickness of 3 sim 8mm taken from core 15

tensile tested The result of one of tensile test is shown inFigure 16 The yield strength of rebar was found between 533and 560MPawhereas their corresponding ultimate strengthswere found between 759 and 878MPaThis yield strengthwashigher than that of the specified yield strength of 400MPa

The loss of rebar thickness due to corrosionwasmeasuredusing Olympus metallurgical camera and Union metallur-gical microscope as shown in Figures 17 and 18 The rebarsamples for this test were obtained from concrete core-drilled Table 5 shows the corrosion thickness of the rebarfor each train This table shows that train EF has the highest

Figure 18 Microstructure with 500x magnification of rebar takenfrom core 15

corrosion rates of 01875ndash05mmyear This corrosion rate ismuch higher than the corrosion rate of trains AB and CDat 00003ndash00006 and 00007ndash00017mmyear respectivelyThese two trains have almost negligible corrosionThe highercorrosion rate observed at train EF is most likely due to localincidence such as local low concrete compaction Thereforethis value should not be used as a representative value ofthe steel corrosion rate of train EF Furthermore as onlyone sample was taken for this test for each train this resultshould be used cautiously and should be comparedwith otherforms of tests or formulae to determine the corrosion rate ofCWICS The representative value of corrosion rate of eachtrain will be discussed and determined in Section 48

44 Determine Depth and Chloride Content and ConcretepH in the Concrete After compression test of core-drilledsample the debris from this test was chloride tested Threedifferent depths were used to measure the chloride contentthat is 00 25 and 50 cm from concrete surface At the sametime the pH of the concrete was alsomeasuredThe results ofchloride test and pH test are presented in Figures 19 and 20respectively

Figure 19 shows that the chloride content measured byweight of concrete (in ) at concrete surface for all samplesis very close to one another except sample taken from core15 Core 15 drilled at train GH shows the highest chloridecontent at all measured depths This highest chloride contentcorrelates with its highest thickness loss of rebar as presentedin Table 5 Figure 19 also indicates that all of the sampleshave a very similar chloride content of 001 at concretedepth of 50mm where the rebar is located This value canbe compared with the chloride threshold level to initiatecorrosion of 0025 such as stipulates in Indonesia ConcreteBuilding Code [2]

Figure 20 shows that the concrete pH is relatively constantas the depth from concrete surface increasesThe lowest pH is


00

0050

010

015

020

0 1 2 3 4 5

Core 1Core 3Core 6

Core 9Core 11Core 15

Chlo

ride c

onte

nt (

)

Depth (cm)

Figure 19 Chloride content at different depths

110

115

120

125

130

0 1 2 3 4 5

Core 1Core 3Core 9


pH

Depth (cm)

Figure 20 pH value at different concrete depth

1125 at concrete surface and 1135 at 5 cmdepthThis indicatesthat the concrete is still in a very high alkaline conditionand has no experience pH reduction due to corrosion attackThis result corroborates with previous result (see Figure 19)which indicate that concrete corrosion has not yet initiatedat CWICS Note that core 15 which has the highest chloridecontent also has the lowest pH at concrete depth of 00 and25mm and the second lowest pH at concrete depth of 50mmCore 15 also has the highest thickness loss of rebar as shownin Table 5

Table 6 Main aggressive element in sea water

Parameter Unit Sample1 2

pH 777 782Sulphate mgL 1600 1585Chloride mgL 14250 14240

45 Determine Chloride and Sulphate Content of Sea WaterSea water surrounding CWICS was tested to determine theconcentration of its main aggressive elements that influencethe degree of chloride attack Two samples were tested andthe results are presented in Table 6 This table shows thatthe highest chloride and sulphate content of the sea wateris 14250mgL and 1600mgL respectively These values arelower than the chloride and sulphate content of sea waterfound in the Persian Gulf [13] at 26800mgL and 3460mgLrespectivelyThese lower contents are possibly caused by highwater rainfall in Indonesia than that in the Persian Gulf

46 Determine the Probability of Corrosion of Rebar The riskof corrosion of rebar in concrete can be estimated usinghalf-cell potential test Half-cell potential test is simplecheap and nondestructive The electrode used for this testis coppercopper sulphate electrode (CSE) The test wasperformed based on ASTM [14] The result of this test issummarized in Table 7

Table 7 shows that the most negative potential of rebar(ie minus0520mV) was found at train CD followed by trainsAB EF and GH All potential readings indicate that thepotential of rebar is already in negative side According toASTMC-876 the potential reading less than minus350mVmeansthat the probability of corrosion of rebar is greater than 90If the result of potential measurement is combined with pHtest (ie minus0520mV and pH 1135) and then plotted usingPourbaix diagram then the corrosion tendency of rebar canbe seen in Figure 21 This figure shows that the concrete ofCWICS is still in noncorroding stage (at passivation zone)This result confirms the result of corrosion rate measurementdiscussed in Section 43 which indicates that the train hasalmost negligible corrosion rate as found in cores 3 and 8However this condition may turn in to corroding stage if theconcrete pH decreases to less than 100

47 Structural and Load Modelling of CWICS Structural andload modeling of CWICS was performed using SAP 2000to determine the internal forces of CWICS These internalforces were then compared with the remaining capacityof CWICSrsquos structural elements The remaining capacityof CWICS has decreased from its initial design capacitydue to rebar corrosion If ratio of the capacity of concreteelement to the internal force of the element (defined herein assafety factor) is greater than unity the element is consideredin a safe condition However if this ratio reaches unityor less the element theoretically has failed and has to bestrengthened to achieve the minimum safety of 10 Note thatthe redundancy effect of this highly indeterminate structure


00

050

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20

0 4 8 12 16pH

Corrosion

Corrosion

Passivation

Immunity

E(V

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minus050

minus10

minus15

Figure 21 Pourbaix diagram of rebar

Figure 22 Structural model of train AB

was not considered in this analysis when safety factor ofelement was determined Therefore it must be mentionedhere that the actual safety factor of CWICS may be higherthan the calculated safety factor obtained from this analysis

Figure 22 shows structural model of CWICS of train ABThe structure comprises beam plate (slab) andwall elementsLoads considered in this analysis were dead live equip-ment and earthquake load To get the maximum internalforces in the concrete element different load combinationis determined based on Indonesia Concrete Code [2] Thedistribution of bendingmoment of train AB due to dead andlive is shown in Figure 23

48 Determine Rate of Deterioration Rate of concrete deteri-oration or corrosion rate can be determined by two followingmethods These are

(i) direct method(ii) indirect method

Direct method of corrosion rate estimation can be per-formed by measuring either weight loss or thickness loss of

585540495450405360315270225180135904500

Figure 23 Bending moment distribution of train AB

Table 7 Half-cell potential measurement of rebar

Number Train AB Train CD Train EF Train GHReadings (mV)

1 minus0380 minus0120 minus0080 minus00902 minus0330 minus0130 minus0090 minus00703 minus0220 minus0090 minus0120 minus01004 minus0370 minus0030 minus0100 minus00705 minus0180 minus0120 minus0110 minus00806 minus0220 minus0090 minus0130 minus01007 minus0120 minus0130 minus0150 minus01208 minus0130 minus0280 minus0130 minus00609 minus0180 minus0140 minus0100 minus008010 minus0200 minus014011 minus0220 minus016012 minus0150 minus012013 minus0180 minus024014 minus0210 minus019015 minus0140 minus018016 minus0050 minus020017 minus0050 minus027018 minus0050 minus032019 minus0050 minus027020 minus0100 minus027021 minus027022 minus034023 minus051024 minus052025 minus0520

Minimum minus0380 minus0520 minus0150 minus0120Maximum minus0050 minus0030 minus0080 minus0060Average minus0177 minus0226 minus0112 minus0086

rebar This method requires the steel sample to be extractedfrom existing structure Table 5 shows the result of directmethod of corrosion rate measurement of CWICSThis tableshows that trains AB and CD have much lower corrosionrate than the newer train GH In this case this methodsyield a contradictory results with actual field condition ofCWICS which shows that older train shows more sign ofdistress than newer train For this reason indirect method of


Table 8 Concrete cover thickness

Location Concrete cover (mm)Min Average

Train AB 500 833Train CD 325 650Train EF 530 740Train GH 440 617

corrosion rate measurement was employed in this study anddirect method wasmainly used for comparison purpose only

Indirect method of corrosion rate estimation was per-formed by using empirical formulae available in manyliteratures These formulae were developed through threedecades of research on corrosion mechanism and will bediscussed briefly in the following paragraph To estimateconcrete rate of deterioration using indirect method theactual concrete cover needs to be measured The thickness ofconcrete cover determines the resistant of concrete structureagainst corrosive agent such as chloride To initiate corrosionchloride must penetrate concrete cover reach the rebar leveland accumulate to chloride threshold level In this studyconcrete cover wasmeasured using Profometer 5+The resultof this test is summarized in Table 8 Note that based on theavailable document the specified concrete cover was 75mm

Table 8 shows that the lowest average concrete cover is617mm found in train GH This value can be comparedwith theminimum cover thickness as specified in IndonesianConcrete Standard [2] which stipulates that the minimumcover for corrosive environment is 65mm However all theminimum cover found during the test does not comply withthe present day code requirement The actual concrete coverfound during this test can be also used as indication of qualitycontrol during construction phase It is very surprising thatthe oldest train (train AB) shows a better quality in termsof cover thickness than the newer trains Train AB has thehighest average concrete cover and the highest minimumconcrete cover at 833mm and 500mm respectively

Deterioration stage of reinforced concrete structure sub-jected to corrosion can be divided in two stages [15]

(i) corrosion initiation(ii) corrosion propagation

The time required for the chloride concentration at thesteel surface to reach the threshold chloride concentrationneeded to destroy the passive layer of the steel is definedas corrosion initiation The second stage is called corrosionpropagationwhere steel reinforcing bar corrodes causing lossof area (metal loss) and reduces flexural and shear strength

Corrosion initiation can be determined using Fickrsquos sec-ond law [16] as

119879119894(119862119900 119862th 119863 119889119888) =

119889119888

2

4119863 [erfminus1 (1 minus (119862th119862119900))]2 (1)

where 119862119900= chloride content at concrete surface 119862th =

threshold chloride content to initiate corrosion119863 = concrete

diffusion coefficient 119889119888= concrete cover and erf = the error

functionChloride content at concrete surface (119862

119900) has been

determined from chloride test discussed at Section 44 whilethreshold chloride content to initiate corrosion (119862th) isprescribed in most concrete codes or used empirical valuesfound in the literature The average and minimum value ofconcrete cover shown in Table 8 can be used in corrosioninitiation calculation to obtain two scenarios of deteriorationthat is average and worst case scenarios

The concrete diffusion coefficient in (1) can be estimatedusing empirical formulae [17] as

119863 = 10minus10+(466wc)

wc=27

1198911015840

cyl + 135

(2)

where wc is the water cement ratio and 1198911015840cyl is the cylindercompressive strength from core-drilled concrete

Corrosion propagation is determined using empiricalformula [15] as

119894corr =270 (1 minus wc)minus164

119889119888

(120583Acm2) (3)

where 119894corr is corrosion rate in 120583Acm2 Note that a corrosioncurrent density of 1 120583Acm2 is equal to a steel section loss of116 120583myear [18]

The above formulae is used to predict the corrosion ratesin concrete structures for mean relative humidity (RH) of80 and mean temperature of 20∘C To obtain corrosion rateat different temperature the following formulae [5] can beutilized

119894corr (119905) = 119894corr-20 [1 + 0073 times (119905 minus 20)] (4)

where 119894corr(119905) = corrosion rate temperature gt 20∘C 119894corr-20 =corrosion rate temperature 20∘C and 119905 = temperature (∘C)

At the present study the average temperature used was31∘C Using this value and (4) the corrosion rate increasesaround 80 compared with corrosion rate at 20∘C

Assuming general uniform corrosion as displayed inFigure 24 the diameter reduction of reinforcing bar (rebar)due to corrosion can be estimated as

Δ119863 (119879119900) = 00232 times 119894corr times 119879119900 (5)

The remaining area of rebar can then be determined as

119860119904(119879119900) =120587

4(119863119900minus 00232 times 119894corr119879119900)

2

(6)

where 119879119900is time measured after corrosion initiation

Using (1) to (6) concrete deterioration then can bedetermined Two scenarios were used for this study

(a) worst case condition scenario(b) average case condition scenario


Table 9 Corrosion initiation time and concrete deterioration rate

Train AB CD EF GHScenarios Worst case Average case Worst case Average case Worst case Average case Worst case Average caseBuilt (year) 1977 1982 1987 1995Operated (year) 1979 1984 1989 1997Compressive strength 1198911015840119888 (MPa) 222 249 378 396 351 374 411 411Cover thickness (mm) 50 83 325 65 53 74 44 617Corrosion initiation (year) 182 1391 573 3556 1025 2613 699 2613Corrosion rate (mmyear) 0229 0100 0118 0056 0081 0053 0079 0056Remaining capacity at 2013 () 44 83 77 100 90 100 94 100Remaining capacity in 20 year () 21 67 59 93 77 92 80 92

Do

Figure 24 General uniform corrosion

In the worst case scenario all parameters used in theanalysis were either the minimum or the maximum valueobtained from the test in order to get the fastest deteriorationof structure For example the minimum value was used forconcrete cover thickness and concrete strength parameterwhereas the maximum value was used for chloride contentparameter By contrast average values of parameters wereused for the average case scenario Table 9 summarizes theresults of analysis using these two scenarios Note thatconcrete strength used in this analysis is concrete strengthobtained from compressive test of concrete core-drilledsamples

Table 9 shows that train AB has the shortest corrosioninitiation time for the worst and average scenarios as ithas the lowest compressive strength This train also has thehighest corrosion rate at around 0229mmyear for worstcase scenario and 01mmyear for average case scenariorespectively It is interesting to compare these corrosion rateswith corrosion rates obtained using direct method as shownin Table 5 The corrosion rate of train AB using indirectmethod for the two scenarios is higher than that obtainedfrom direct method which gives corrosion rate of 00003ndash00006mmyear Therefore corrosion rate based on indirectmethod yieldsmore conservative results than that fromdirectmethod For this reason the corrosion rate from indirectmethod will be used for determining the remaining capacityof CWICS

Based on the above assumption for the worst casescenario the remaining capacity of train AB at 2013 is 44of the initial capacity However for the average conditionscenario the-2013 capacity of train AB is around 83 ofthe initial capacity This average condition appears to betterrepresent the actual train condition as up to now this train

is still in service and there is no indication of significant ofdistress of the train

Table 9 also indicates that for average case scenario theremaining capacity of train CD EF and GH at year 2013is still 100 of their initial design capacities By year 2033these remaining capacities have decreased to 93 92 and92 respectively By comparison for worst case scenario theremaining capacity of these trains at year 2013 are 77 90and 94 of their initial design capacities respectively By year2033 these remaining capacities reduce to 59 77 and 80of their initial design capacity respectively

49 Determine Safety Factor To better capture the currentcondition of CWICS the reduction of safety factor of differ-ent element of CWICS due to rebar corrosion against flexureand shear action will be presented Only the result of analysisof train AB will be discussed in the next section as this trainhas the worst condition

The safety factor of concrete element against flexure andshear can be formulated as

SF =120593119872119899(119879119900)

119872119906

gt 10 (7)

SF =120593119881119899(119879119900)

119881119906

gt 10 (8)

where 119872119899(119879119900) = nominal flexural capacity of concrete ele-

ment at 119879119900after corrosion has initiated 119872

119906= flexural

moment due to factor load obtained from structural analysis119881119899(119879119900) = nominal shear capacity of concrete element at 119879

119900

after corrosion has initiated and119881119906= shear due to factor load

obtained from structural analysisThe capacity of concrete element against flexure and shear

at 119879119900can be determined as

119872119899(119879119900) = 119860

119904(119879119900) times 119891119910times 08 times 119889 (9)

119881119899(119879119900) =1

6radic1198911015840119888times 119887119908times 119889 +

119860V (119879119900) times 119891119910 times 119889

119904 (10)

where 119860119904(119879119900) = area of rebar section at time 119879

119900 119891119910=

yield strength of rebar ℎ = height of section 1198911015840119888= concrete

compressive strength 119887119908= width of section 119889 = effective


02

04

06

08

10

12

14

16

1970 1980 1990 2000 2010 2020 2030 2040

Average caseWorst case

Safe

ty fa

ctor

Year

Figure 25 Safety factor for plate element with 600mm depth andreinforced with 19mm diameter rebar at 150 mm spacing

depth of section119860V(119879119900) = area of shear reinforcement at time119879119900 and 119904 = spacing of shear reinforcementThe area of rebar for flexure defined as 119860

119904(119879119900) and for

shear defined as 119860V(119879119900) can then be determined using (6)For the purpose of this study the safety was determined atyear 2013 and year 2033 using (7) to (10) Figure 25 showsthe reduction of safety factor for concrete plate element with600mm depth and reinforced with 19mm rebar diameter at150mm spacing

Figure 25 indicates that for average case scenarios thesafety factor of 600mm plate element decreases from 148to 106 at year 2013 and to 082 at year 2033 respectivelyBy comparison for worst case scenarios the safety factordecreases from 148 to 057 at year 2013 and to 021 at year2033 respectivelyTherefore this element requires immediatestrengthening as the safety factor already approaches 10 atyear 2013

Figure 26 shows the reduction of safety factor for concretewall element with 600mm depth and reinforced with 22mmdiameter rebar at 150mm spacing This figure indicates thatfor average case scenarios the safety factor of 600mm wallelement decreases from 254 to 195 at year 2013 and to162 at year 2033 respectively By comparison for worst casescenarios the safety factor decreases from 254 to 120 at year2013 and to 058 at year 2033 respectively Thus this elementdoes not require immediate strengthening as the safety factoris still greater than 10 at year 2013 for both scenarios

Figure 27 shows the reduction of safety factor for beamelementwith 500mmtimes 800mmcross-section and reinforcedwith 4D28mm diameter rebar against flexure This figureindicates that for average case scenarios the safety factorof the beam decreases from 246 to 194 at year 2013 and to

0500

100

150

200

250

300

1970 1980 1990 2000 2010 2020 2030 2040


Safe

ty fa

ctor

Year

Figure 26 Safety factor for wall element with 600mm depth andreinforced with 22mm diameter rebar at 150mm spacing

0500

100

150

200

250

1970 1980 1990 2000 2010 2020 2030 2040


Safe

ty fa

ctor

Year

Figure 27 Safety factor for beam element with 500mm times 800mmcross-section reinforced with 4D28mm diameter rebar againstflexure

165 at year 2033 respectively By comparison for worst casescenarios the safety factor decreases from 246 to 133 at year2013 and to 081 at year 2033 respectively Thus this beamdoes not require immediate strengthening as the safety factoris still greater than 10 at year 2013


200

250

300

350

400

450

1970 1980 1990 2000 2010 2020 2030 2040


Safe

ty fa

ctor

Year

Figure 28 Safety factor for beam element with 500mm times 800mmcross-section and shear reinforced with 2D12mm diameter rebarwith 150mm spacing against shear

Figure 28 shows the reduction of safety factor for beamelement with 500mm times 800mm cross-section and shearreinforced with 2D12mm diameter rebar with 150mm spac-ing against shear This figure indicates that for average casescenarios the safety factor of the beam decreases from 436to 339 at year 2013 and to 297 at year 2033 respectivelyBy comparison for worst case scenarios the safety factordecreases from 436 to 248 at year 2013 and to 224 atyear 2033 respectively Thus this beam does not requireimmediate strengthening as the safety factor is still greaterthan 10 at year 2013

It should be mentioned here that the remaining lifeassessment of concrete structure due to corrosion attack alsohas some limitations Some of themodels used in the analysisare derived based on idealized condition For example theassumption used for corrosion initiation model based onFickrsquos second law given in (1) may not be in agreement withthe actual service conditions Fickrsquos second law assumes thatconcrete is homogeneous material and relative in moist con-dition (saturated) In reality concrete cover is generally notsaturated with water concrete is a nonhomogeneousmaterialdue to the presence of microcracking interconnected poresand aggregated particles and the diffusion coefficient119863maychange with time due to hydration progress [19] Thereforethe remaining life assessment of reinforce concrete structureshould be combined with engineering judgment and shouldbe validated with the actual field condition Further theremaining life assessment should be performed every 5ndash10 years as conditions may change significantly than thosepredicted by available deterioration model

5 Conclusions

Themain conclusions drawn from this study can be summa-rized as follows

(i) From field and laboratory tests no significant cor-rosion activity has been found at CWICS Most ofthe reinforcing bars were still in a relatively passivecondition as concrete surrounding the reinforcingbars was still in a high alkaline stage Furthermorethe chloride level at rebar position was found around001 by weight of concreteThis value was still belowchloride threshold level to initiate corrosion given inSNI-03-2847 at 0025

(ii) From compressive test of core-drilled sample trainAB has the lowest average strength of all samplesHowever in terms of cover thickness train AB hasthe highest cover thickness of all trains

(iii) Due to its lowest compressive strength obtained fromcompression test of core-drilled sample train AB hasthe highest corrosion rate for all trains

(iv) Based on the available data compiled from the teststwo different scenarios were used to estimate theremaining life of CWICS Using this approach theaverage case scenario represented closer to the actualcondition than that of the worst case scenario Theanalysis using worst case scenario for train AB givesthe remaining capacity of 40 of the initial capacityThis result does not represent the existing conditionof CWICS which shows no significant sign of distressup to the present By contrast using average casescenario for train AB gives the remaining capacity of83 of the initial capacity

(v) Structural analysis shows that the safety factor ofmostconcrete elements of CWICS was still higher thanunity up to year 2033 However fewer elements werealso found to have safety factor approach to unityat year 2013 These elements with low safety factorrequire immediate strengthening to fulfill its intendedservice life up to 2033

Conflict of Interests

The authors declare that there is no conflict of interestsregarding the publication of this paper

Acknowledgments

The authors greatly acknowledge the support of MaterialTesting Laboratory of Civil Engineering Diploma Programand the Institute of Research and Community Services ofInstitut Teknologi Sepuluh Nopember (ITS) during field andlaboratory investigation of the study

References

[1] A Neville ldquoChloride attack of reinforced concrete an over-viewrdquoMaterials and Structures vol 28 no 2 pp 63ndash70 1995


[2] ldquoTata Cara Perhitungan Struktur Beton untuk BangunanGedung (Indonesia concrete building code)rdquo SNI-03-28472013

[3] P K Mehta Concrete in the Marine Environment Taylor ampFrancis New York NY USA 2003

[4] H S Muller M Haist and M Vogel ldquoAssessment of thesustainability potential of concrete and concrete structuresconsidering their environmental impact performance and life-timerdquo Construction and Building Materials vol 67 pp 321ndash3372014

[5] DuraCreteProbabilistic Performance BasedDurability Design ofConcrete Structures 2000

[6] BS-1881Part203 Recommendations for Measurement of Velocityof Ultrasonic Pulses in Concrete British Standards InstitutionLondon UK 1986

[7] ACI-Committee-2281R-03 In-Place Methods to Estimate Con-crete Strength Building American Concrete Institute Farming-ton Hills Mich USA 2003

[8] P K Mehta and P J M Monteiro Concrete MicrostructureProperties and Materials McGraw-Hill 3rd edition 2006

[9] RILEM-Recommendations ldquoAbsorption of water by immersionunder vacuum Materials and structuresrdquo in RILEM CPC 113vol 101 pp 393ndash394 1984

[10] X Chen SWu and J Zhou ldquoInfluence of porosity on compres-sive and tensile strength of cement mortarrdquo Construction andBuilding Materials vol 40 pp 869ndash874 2013

[11] Y Y Kim K M Lee J W Bang and S J Kwon ldquoEffect of WCratio on durability and porosity in cementmortar with constantcement amountrdquoAdvances inMaterials Science andEngineeringvol 2014 Article ID 273460 11 pages 2014

[12] BS-EN-14630 Products and Systems for the Protection andRepair of Concrete Structures Test Methods Determination ofCarbonationDepth inHardenedConcrete by the PhenolphthaleinMethod British Standards Institution London UK 2006

[13] M Shekarchi F Moradi-Marani and F Pargar ldquoCorrosiondamage of a reinforced concrete jetty structure in the PersianGulf a case studyrdquo Structure and Infrastructure EngineeringMaintenance Management Life-Cycle Design and Performancevol 7 no 9 pp 701ndash713 2011

[14] ASTM-C-876 ldquoStandard test method for half-cell potentials ofuncoated reinforcing steel in concreterdquo inAnnual Book of ASTMStandards vol 0302 pp 11ndash16 2006

[15] K A T Vu andM G Stewart ldquoStructural reliability of concretebridges including improved chloride-induced corrosion mod-elsrdquo Structural Safety vol 22 no 4 pp 313ndash333 2000

[16] J Zhang and Z Lounis ldquoSensitivity analysis of simplifieddiffusion-based corrosion initiation model of concrete struc-tures exposed to chloridesrdquo Cement and Concrete Research vol36 no 7 pp 1312ndash1323 2006

[17] M G Stewart and D V Rosowsky ldquoStructural safety andserviceability of concrete bridges subject to corrosionrdquo Journalof Infrastructure Systems vol 4 no 4 pp 146ndash155 1998

[18] D A Jones ldquoLocalized surface plasticity during stress corrosioncrackingrdquo Corrosion vol 52 no 5 pp 356ndash362 1996

[19] J-K Kim C-Y Kim S-T Yi and Y Lee ldquoEffect of carbonationon the rebound number and compressive strength of concreterdquoCement and Concrete Composites vol 31 no 2 pp 139ndash1442009

International Journal of

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Chemical EngineeringInternational Journal of Antennas and

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Navigation and Observation



DistributedSensor Networks



Figure 1 Cracking of concrete plate (slab) of CWICS

and delamination of concrete see Figure 1 These damagesindicate that the chlorides may have already penetratedconcrete cover reached rebar level and accumulated tothreshold level chloride concentration to initiate corrosionThe corrosionmay have reduced rebar cross-section and leadto a reduced strength capacity of some structural elementsof CWICS If this condition is not rectified soon it mayendanger the whole structure of CWICS and shut down thefactory operation The shutdown of the factory can lead tosignificant loss of revenue to factory owner

The purpose of this study can be summarized as follows

(i) determine current existing condition of CWICS

(ii) determine remaining life of CWICS

(a) determine the safety factor of CWICS at year2013

(b) determine the safety factor of CWICS at year2033

3 Structural Configuration of Cooling WaterIntake Concrete Structure

Cooling water intake concrete structure (CWICS) is madeof concrete structure supported by steel piles The concretestructure of CWICS comprises plate (slab) beam and wallelements A steel frame is installed on the top of CWICSfor a crane operation (see Figure 2) In addition a numberof machines for pumping sea water are stationed on top ofthe concrete structure Most of these machines run for 24hours without stopping CWICS consists of 4 trains whichhas almost similar structural configuration These are trainsAB CD EF and GH built in 1977 1982 1987 and 1995respectively These trains were built by different contractors

4 Methodology

To determine remaining service life of CWICS the currentcondition of CWICS needs to be investigated and rate ofdeterioration needs to be determined The ultimate goal ofthis study was to determine whether CWICS can fulfill itsintended service life up to 2033 without strengthening To

Figure 2 Front view of CWICS

achieve this goal the following steps and tests were employedin this study

(i) Collect information regarding design criteria fromavailable document and as-built drawing and anychanges might occur during service period

(ii) Determine current concrete density and concretecompressive strength of CWICS

(a) Compression test of core-drilled concrete sam-ple

(b) Ultrasonic pulse velocity (UPV) test(c) Hammer test(d) Porosity test

(iii) Determine carbonation depth

(a) Phenolphthalein test

(iv) Determine yield strength of rebar and remaining steelrebar thickness

(a) Tension test of rebar samples taken from core-drilled concrete samples

(b) Thickness loss measurement of corroded rebar

(v) Determine chloride content and pH of the concrete atdifferent depth

(a) Chloride content test from core-drilled concretesamples

(b) pH test

(vi) Determine chloride and sulphate contents of seawa-ter

(vii) Determine probability of corrosion of rebar

(a) Half-cell potential measurement

(viii) Structural and load modeling of CWICS using avail-able finite element program to determine the internalforces


















C1

C2C4

C3C5

4

3

22

1

4

7810

32-E-M-218(SIM)

EL +485

200

925

Drain pipe

3250

H

400 deeptrench

9790

EL +400


200

1200

0

EL +485

4000

TYP

A

Open

Hp EL +385

Open

Open Open

OpenOpen

Open OpenOpen

OpenEL +400

(TYP)

EL +404

EL +380

(TYP)

Open

OpenOpen

Open

Open Open

Open Open

Open

OpenOpen

OpenEL +320

Open

EL +505(TYP)

LP EL 322(TYP)

HPE +325(TYP)

Protectivecrub

Pipe supportTYP

DWGNO 32-E-M-209

EL +445(TYP) 20

0

200

250

2500

725

2075

200

925

250PIER

CW pump5800

5800

CLCL

C L

C L

C LC L

C LCLCLCL

CLCL

CL

CL CL CL CLCLPIER

CW pump

5800PIER

5800CW pump

5800PIER

5800CW pump

5800PIER

5800CW pump

5800PIER

2900

N

2650

250PIER 5500

Roadway6000

A

Open

Open

Open

Open

Open

Open

Open Open Open

Open

Open

Open Open

drain

strai

ner

1254

strai

ner48

50

7600

4350

CW

pum

psFW

pum

ps

3950

1750

3700

1850

1850

Trav

scre

ens

2100

2200

0

2120

1680

2940

2160

Open

Open

Open

Open

39984009984000 pipe drain

39984009984000 pipe







4

3

22

1

4

7810

32-E-M-218(SIM)

EL +485

200

925

Drain pipe

3250

H

400 deeptrench

9790

EL +400


200

1200

0

EL +485

4000

TYP

A

Open

HP EL +385

Open

Open Open

OpenOpen

Open OpenOpen

OpenEL +400

(TYP)

EL +404

EL +380

(TYP)

Open

OpenOpen

Open

Open Open

Open Open

Open

OpenOpen

OpenEL +320

Open

EL +505(TYP)

LP EL 322(TYP)

HPE +325(TYP)

Protectivecurb

Pipe supportTYP

DWGNO 32-E-M-209

EL +445(TYP) 20

0

200

250

2500

725

2075

200

925

250PIER

CW pump5800

5800PIER

CW pump

5800PIER

5800CW pump

5800PIER

5800CW pump

5800PIER

5800CW pump

5800PIER

2900

N

2650

250PIER 5500

Roadway6000

A

Open

Open

Open

Open

Open

Open

Open Open Open

Open

Open

Open Open

drain

strai

ner

1254

strai

ner48

50

7600

4350

CW

pum

psFW

pum

ps

3950

1750

3700

1850

1850

Trav

scre

ens

2100

2200

0

2120

1680

2940

2160

Open

Open

Open

Open

U1

U3U8

U5U10

U2

U4

U6

U7

U9

U11

U12

CLCL

C L

C L

C LC L

C L

CL

CLCLCL

CL CL CL CL CLCL

39984009984000 pipe drain

39984009984000 pipe








4

3

22

1

4

7810

32-E-M-218(SIM)

EL +485

200

925

Drain pipe

3250

H

400 deeptrench

9790

EL +400


200

1200

0

EL +485

4000

TYP

A

Open

HP EL +385

Open

Open Open

OpenOpen

Open OpenOpen

OpenEL +400

(TYP)

EL +404

EL +380

(TYP)

Open

OpenOpen

Open

Open Open

Open Open

Open

OpenOpen

OpenEL +320

Open

EL +505(TYP)

LP EL 322(TYP)

HPE +325(TYP)

Protectivecrub

Pipe supportTYP

DWGNO 32-E-M-209

EL +445(TYP) 20

0

200

250

2500

725

2075

200

925

250PIER

CW pump5800

5800

CLCL

C L

C L

C LC L

C LCLCLCL

CLCL

CL

CL CL CL CLCLPIER

CW pump

5800PIER

5800CW pump

5800PIER

5800CW pump

5800PIER

5800CW pump

5800PIER

2900

N

2650

250PIER 5500

Roadway6000

A

Open

Open

Open

Open

Open

Open

Open Open Open

Open

Open

Open Open

drain

strai

ner

1254

strai

ner48

50

7600

4350

CW

pum

psFW

pum

ps

3950

1750

3700

1850

1850

Trav

scre

ens

2100

2200

0

2120

1680

2940

2160

Open

Open

Open

Open

39984009984000 pipe drain

39984009984000 pipe

H1

H3H8

H5H10

H2

H4

H6

H7

H9

H11

H12

H39

H40










220

230

240

250

260

270

280


Com

pres

sion

stren

gth

(kg

cm2)

y = 14941 + 0040568x R = 099739


375

380

385

390

395

400

405

410


Com

pres

sion

stren

gth

(kg

cm2)

y = 35616 + 0015232x R = 032005



350

360

370

380

390

400


Com

pres

sion

stren

gth

(kg

cm2)

y = 50195 minus 0062572x R = 058026


29 30 31 32 33 34 35375

380

385

390

395

400

405

410

Rebound number

Com

pres

sion

stren

gth

(kg

cm2)

y = minus13465 + 011432x R = 072089





28 29 30 31 32 33 34 35200

250

300

350

400

450

Rebound number

Com

pres

sion

stren

gth

(kg

cm2)

y = 28479 + 00077793x R = 019884







200

250

300

350

400

450

4 5 6 7 8 9 10 11 12Porosity ()

Com

pres

sion

stren

gth

(kg

cm2)

y = 4969 minus 18797x R = 053944








0 5 10 15 20 250

10

20

30

40

50

60

70

80

Strain ()

Tens

ion

(KN

)











00

0050

010

015

020

0 1 2 3 4 5

Core 1Core 3Core 6


Chlo

ride c

onte

nt (

)

Depth (cm)


110

115

120

125

130

0 1 2 3 4 5

Core 1Core 3Core 9


pH

Depth (cm)











00

050

10

15

20

0 4 8 12 16pH

Corrosion

Corrosion

Passivation

Immunity

E(V

)

minus050

minus10

minus15








585540495450405360315270225180135904500


















119879119894(119862119900 119862th 119863 119889119888) =

119889119888

2






119900) has been



119863 = 10minus10+(466wc)

wc=27

1198911015840

cyl + 135

(2)




119889119888

(120583Acm2) (3)









119860119904(119879119900) =120587

4(119863119900minus 00232 times 119894corr119879119900)

2

(6)







Do









SF =120593119872119899(119879119900)

119872119906

gt 10 (7)

SF =120593119881119899(119879119900)

119881119906

gt 10 (8)



119906= flexural


119900




119872119899(119879119900) = 119860


119881119899(119879119900) =1


119860V (119879119900) times 119891119910 times 119889

119904 (10)


119900 119891119910=




02

04

06

08

10

12

14

16

1970 1980 1990 2000 2010 2020 2030 2040


Safe

ty fa

ctor

Year



119904(119879119900) and for





0500

100

150

200

250

300

1970 1980 1990 2000 2010 2020 2030 2040


Safe

ty fa

ctor

Year


0500

100

150

200

250

1970 1980 1990 2000 2010 2020 2030 2040


Safe

ty fa

ctor

Year




200

250

300

350

400

450

1970 1980 1990 2000 2010 2020 2030 2040


Safe

ty fa

ctor

Year




5 Conclusions









Acknowledgments


References























RoboticsJournal of





Journal of



RotatingMachinery





VLSI Design



Shock and Vibration







Journal of



Volume 2014


SensorsJournal of





Propagation


























C1

C2C4

C3C5

4

3

22

1

4

7810

32-E-M-218(SIM)

EL +485

200

925

Drain pipe

3250

H

400 deeptrench

9790

EL +400


200

1200

0

EL +485

4000

TYP

A

Open

Hp EL +385

Open

Open Open

OpenOpen

Open OpenOpen

OpenEL +400

(TYP)

EL +404

EL +380

(TYP)

Open

OpenOpen

Open

Open Open

Open Open

Open

OpenOpen

OpenEL +320

Open

EL +505(TYP)

LP EL 322(TYP)

HPE +325(TYP)

Protectivecrub

Pipe supportTYP

DWGNO 32-E-M-209

EL +445(TYP) 20

0

200

250

2500

725

2075

200

925

250PIER

CW pump5800

5800

CLCL

C L

C L

C LC L

C LCLCLCL

CLCL

CL

CL CL CL CLCLPIER

CW pump

5800PIER

5800CW pump

5800PIER

5800CW pump

5800PIER

5800CW pump

5800PIER

2900

N

2650

250PIER 5500

Roadway6000

A

Open

Open

Open

Open

Open

Open

Open Open Open

Open

Open

Open Open

drain

strai

ner

1254

strai

ner48

50

7600

4350

CW

pum

psFW

pum

ps

3950

1750

3700

1850

1850

Trav

scre

ens

2100

2200

0

2120

1680

2940

2160

Open

Open

Open

Open

39984009984000 pipe drain

39984009984000 pipe







4

3

22

1

4

7810

32-E-M-218(SIM)

EL +485

200

925

Drain pipe

3250

H

400 deeptrench

9790

EL +400


200

1200

0

EL +485

4000

TYP

A

Open

HP EL +385

Open

Open Open

OpenOpen

Open OpenOpen

OpenEL +400

(TYP)

EL +404

EL +380

(TYP)

Open

OpenOpen

Open

Open Open

Open Open

Open

OpenOpen

OpenEL +320

Open

EL +505(TYP)

LP EL 322(TYP)

HPE +325(TYP)

Protectivecurb

Pipe supportTYP

DWGNO 32-E-M-209

EL +445(TYP) 20

0

200

250

2500

725

2075

200

925

250PIER

CW pump5800

5800PIER

CW pump

5800PIER

5800CW pump

5800PIER

5800CW pump

5800PIER

5800CW pump

5800PIER

2900

N

2650

250PIER 5500

Roadway6000

A

Open

Open

Open

Open

Open

Open

Open Open Open

Open

Open

Open Open

drain

strai

ner

1254

strai

ner48

50

7600

4350

CW

pum

psFW

pum

ps

3950

1750

3700

1850

1850

Trav

scre

ens

2100

2200

0

2120

1680

2940

2160

Open

Open

Open

Open

U1

U3U8

U5U10

U2

U4

U6

U7

U9

U11

U12

CLCL

C L

C L

C LC L

C L

CL

CLCLCL

CL CL CL CL CLCL

39984009984000 pipe drain

39984009984000 pipe








4

3

22

1

4

7810

32-E-M-218(SIM)

EL +485

200

925

Drain pipe

3250

H

400 deeptrench

9790

EL +400


200

1200

0

EL +485

4000

TYP

A

Open

HP EL +385

Open

Open Open

OpenOpen

Open OpenOpen

OpenEL +400

(TYP)

EL +404

EL +380

(TYP)

Open

OpenOpen

Open

Open Open

Open Open

Open

OpenOpen

OpenEL +320

Open

EL +505(TYP)

LP EL 322(TYP)

HPE +325(TYP)

Protectivecrub

Pipe supportTYP

DWGNO 32-E-M-209

EL +445(TYP) 20

0

200

250

2500

725

2075

200

925

250PIER

CW pump5800

5800

CLCL

C L

C L

C LC L

C LCLCLCL

CLCL

CL

CL CL CL CLCLPIER

CW pump

5800PIER

5800CW pump

5800PIER

5800CW pump

5800PIER

5800CW pump

5800PIER

2900

N

2650

250PIER 5500

Roadway6000

A

Open

Open

Open

Open

Open

Open

Open Open Open

Open

Open

Open Open

drain

strai

ner

1254

strai

ner48

50

7600

4350

CW

pum

psFW

pum

ps

3950

1750

3700

1850

1850

Trav

scre

ens

2100

2200

0

2120

1680

2940

2160

Open

Open

Open

Open

39984009984000 pipe drain

39984009984000 pipe

H1

H3H8

H5H10

H2

H4

H6

H7

H9

H11

H12

H39

H40










220

230

240

250

260

270

280


Com

pres

sion

stren

gth

(kg

cm2)

y = 14941 + 0040568x R = 099739


375

380

385

390

395

400

405

410


Com

pres

sion

stren

gth

(kg

cm2)

y = 35616 + 0015232x R = 032005



350

360

370

380

390

400


Com

pres

sion

stren

gth

(kg

cm2)

y = 50195 minus 0062572x R = 058026


29 30 31 32 33 34 35375

380

385

390

395

400

405

410

Rebound number

Com

pres

sion

stren

gth

(kg

cm2)

y = minus13465 + 011432x R = 072089





28 29 30 31 32 33 34 35200

250

300

350

400

450

Rebound number

Com

pres

sion

stren

gth

(kg

cm2)

y = 28479 + 00077793x R = 019884







200

250

300

350

400

450

4 5 6 7 8 9 10 11 12Porosity ()

Com

pres

sion

stren

gth

(kg

cm2)

y = 4969 minus 18797x R = 053944








0 5 10 15 20 250

10

20

30

40

50

60

70

80

Strain ()

Tens

ion

(KN

)











00

0050

010

015

020

0 1 2 3 4 5

Core 1Core 3Core 6


Chlo

ride c

onte

nt (

)

Depth (cm)


110

115

120

125

130

0 1 2 3 4 5

Core 1Core 3Core 9


pH

Depth (cm)











00

050

10

15

20

0 4 8 12 16pH

Corrosion

Corrosion

Passivation

Immunity

E(V

)

minus050

minus10

minus15








585540495450405360315270225180135904500


















119879119894(119862119900 119862th 119863 119889119888) =

119889119888

2






119900) has been



119863 = 10minus10+(466wc)

wc=27

1198911015840

cyl + 135

(2)




119889119888

(120583Acm2) (3)









119860119904(119879119900) =120587

4(119863119900minus 00232 times 119894corr119879119900)

2

(6)







Do









SF =120593119872119899(119879119900)

119872119906

gt 10 (7)

SF =120593119881119899(119879119900)

119881119906

gt 10 (8)



119906= flexural


119900




119872119899(119879119900) = 119860


119881119899(119879119900) =1


119860V (119879119900) times 119891119910 times 119889

119904 (10)


119900 119891119910=




02

04

06

08

10

12

14

16

1970 1980 1990 2000 2010 2020 2030 2040


Safe

ty fa

ctor

Year



119904(119879119900) and for





0500

100

150

200

250

300

1970 1980 1990 2000 2010 2020 2030 2040


Safe

ty fa

ctor

Year


0500

100

150

200

250

1970 1980 1990 2000 2010 2020 2030 2040


Safe

ty fa

ctor

Year




200

250

300

350

400

450

1970 1980 1990 2000 2010 2020 2030 2040


Safe

ty fa

ctor

Year




5 Conclusions









Acknowledgments


References























RoboticsJournal of





Journal of



RotatingMachinery





VLSI Design



Shock and Vibration







Journal of



Volume 2014


SensorsJournal of





Propagation










4

3

22

1

4

7810

32-E-M-218(SIM)

EL +485

200

925

Drain pipe

3250

H

400 deeptrench

9790

EL +400


200

1200

0

EL +485

4000

TYP

A

Open

HP EL +385

Open

Open Open

OpenOpen

Open OpenOpen

OpenEL +400

(TYP)

EL +404

EL +380

(TYP)

Open

OpenOpen

Open

Open Open

Open Open

Open

OpenOpen

OpenEL +320

Open

EL +505(TYP)

LP EL 322(TYP)

HPE +325(TYP)

Protectivecurb

Pipe supportTYP

DWGNO 32-E-M-209

EL +445(TYP) 20

0

200

250

2500

725

2075

200

925

250PIER

CW pump5800

5800PIER

CW pump

5800PIER

5800CW pump

5800PIER

5800CW pump

5800PIER

5800CW pump

5800PIER

2900

N

2650

250PIER 5500

Roadway6000

A

Open

Open

Open

Open

Open

Open

Open Open Open

Open

Open

Open Open

drain

strai

ner

1254

strai

ner48

50

7600

4350

CW

pum

psFW

pum

ps

3950

1750

3700

1850

1850

Trav

scre

ens

2100

2200

0

2120

1680

2940

2160

Open

Open

Open

Open

U1

U3U8

U5U10

U2

U4

U6

U7

U9

U11

U12

CLCL

C L

C L

C LC L

C L

CL

CLCLCL

CL CL CL CL CLCL

39984009984000 pipe drain

39984009984000 pipe








4

3

22

1

4

7810

32-E-M-218(SIM)

EL +485

200

925

Drain pipe

3250

H

400 deeptrench

9790

EL +400


200

1200

0

EL +485

4000

TYP

A

Open

HP EL +385

Open

Open Open

OpenOpen

Open OpenOpen

OpenEL +400

(TYP)

EL +404

EL +380

(TYP)

Open

OpenOpen

Open

Open Open

Open Open

Open

OpenOpen

OpenEL +320

Open

EL +505(TYP)

LP EL 322(TYP)

HPE +325(TYP)

Protectivecrub

Pipe supportTYP

DWGNO 32-E-M-209

EL +445(TYP) 20

0

200

250

2500

725

2075

200

925

250PIER

CW pump5800

5800

CLCL

C L

C L

C LC L

C LCLCLCL

CLCL

CL

CL CL CL CLCLPIER

CW pump

5800PIER

5800CW pump

5800PIER

5800CW pump

5800PIER

5800CW pump

5800PIER

2900

N

2650

250PIER 5500

Roadway6000

A

Open

Open

Open

Open

Open

Open

Open Open Open

Open

Open

Open Open

drain

strai

ner

1254

strai

ner48

50

7600

4350

CW

pum

psFW

pum

ps

3950

1750

3700

1850

1850

Trav

scre

ens

2100

2200

0

2120

1680

2940

2160

Open

Open

Open

Open

39984009984000 pipe drain

39984009984000 pipe

H1

H3H8

H5H10

H2

H4

H6

H7

H9

H11

H12

H39

H40










220

230

240

250

260

270

280


Com

pres

sion

stren

gth

(kg

cm2)

y = 14941 + 0040568x R = 099739


375

380

385

390

395

400

405

410


Com

pres

sion

stren

gth

(kg

cm2)

y = 35616 + 0015232x R = 032005



350

360

370

380

390

400


Com

pres

sion

stren

gth

(kg

cm2)

y = 50195 minus 0062572x R = 058026


29 30 31 32 33 34 35375

380

385

390

395

400

405

410

Rebound number

Com

pres

sion

stren

gth

(kg

cm2)

y = minus13465 + 011432x R = 072089





28 29 30 31 32 33 34 35200

250

300

350

400

450

Rebound number

Com

pres

sion

stren

gth

(kg

cm2)

y = 28479 + 00077793x R = 019884







200

250

300

350

400

450

4 5 6 7 8 9 10 11 12Porosity ()

Com

pres

sion

stren

gth

(kg

cm2)

y = 4969 minus 18797x R = 053944








0 5 10 15 20 250

10

20

30

40

50

60

70

80

Strain ()

Tens

ion

(KN

)











00

0050

010

015

020

0 1 2 3 4 5

Core 1Core 3Core 6


Chlo

ride c

onte

nt (

)

Depth (cm)


110

115

120

125

130

0 1 2 3 4 5

Core 1Core 3Core 9


pH

Depth (cm)











00

050

10

15

20

0 4 8 12 16pH

Corrosion

Corrosion

Passivation

Immunity

E(V

)

minus050

minus10

minus15








585540495450405360315270225180135904500


















119879119894(119862119900 119862th 119863 119889119888) =

119889119888

2






119900) has been



119863 = 10minus10+(466wc)

wc=27

1198911015840

cyl + 135

(2)




119889119888

(120583Acm2) (3)









119860119904(119879119900) =120587

4(119863119900minus 00232 times 119894corr119879119900)

2

(6)







Do









SF =120593119872119899(119879119900)

119872119906

gt 10 (7)

SF =120593119881119899(119879119900)

119881119906

gt 10 (8)



119906= flexural


119900




119872119899(119879119900) = 119860


119881119899(119879119900) =1


119860V (119879119900) times 119891119910 times 119889

119904 (10)


119900 119891119910=




02

04

06

08

10

12

14

16

1970 1980 1990 2000 2010 2020 2030 2040


Safe

ty fa

ctor

Year



119904(119879119900) and for





0500

100

150

200

250

300

1970 1980 1990 2000 2010 2020 2030 2040


Safe

ty fa

ctor

Year


0500

100

150

200

250

1970 1980 1990 2000 2010 2020 2030 2040


Safe

ty fa

ctor

Year




200

250

300

350

400

450

1970 1980 1990 2000 2010 2020 2030 2040


Safe

ty fa

ctor

Year




5 Conclusions









Acknowledgments


References























RoboticsJournal of





Journal of



RotatingMachinery





VLSI Design



Shock and Vibration







Journal of



Volume 2014


SensorsJournal of





Propagation










4

3

22

1

4

7810

32-E-M-218(SIM)

EL +485

200

925

Drain pipe

3250

H

400 deeptrench

9790

EL +400


200

1200

0

EL +485

4000

TYP

A

Open

HP EL +385

Open

Open Open

OpenOpen

Open OpenOpen

OpenEL +400

(TYP)

EL +404

EL +380

(TYP)

Open

OpenOpen

Open

Open Open

Open Open

Open

OpenOpen

OpenEL +320

Open

EL +505(TYP)

LP EL 322(TYP)

HPE +325(TYP)

Protectivecrub

Pipe supportTYP

DWGNO 32-E-M-209

EL +445(TYP) 20

0

200

250

2500

725

2075

200

925

250PIER

CW pump5800

5800

CLCL

C L

C L

C LC L

C LCLCLCL

CLCL

CL

CL CL CL CLCLPIER

CW pump

5800PIER

5800CW pump

5800PIER

5800CW pump

5800PIER

5800CW pump

5800PIER

2900

N

2650

250PIER 5500

Roadway6000

A

Open

Open

Open

Open

Open

Open

Open Open Open

Open

Open

Open Open

drain

strai

ner

1254

strai

ner48

50

7600

4350

CW

pum

psFW

pum

ps

3950

1750

3700

1850

1850

Trav

scre

ens

2100

2200

0

2120

1680

2940

2160

Open

Open

Open

Open

39984009984000 pipe drain

39984009984000 pipe

H1

H3H8

H5H10

H2

H4

H6

H7

H9

H11

H12

H39

H40










220

230

240

250

260

270

280


Com

pres

sion

stren

gth

(kg

cm2)

y = 14941 + 0040568x R = 099739


375

380

385

390

395

400

405

410


Com

pres

sion

stren

gth

(kg

cm2)

y = 35616 + 0015232x R = 032005



350

360

370

380

390

400


Com

pres

sion

stren

gth

(kg

cm2)

y = 50195 minus 0062572x R = 058026


29 30 31 32 33 34 35375

380

385

390

395

400

405

410

Rebound number

Com

pres

sion

stren

gth

(kg

cm2)

y = minus13465 + 011432x R = 072089





28 29 30 31 32 33 34 35200

250

300

350

400

450

Rebound number

Com

pres

sion

stren

gth

(kg

cm2)

y = 28479 + 00077793x R = 019884







200

250

300

350

400

450

4 5 6 7 8 9 10 11 12Porosity ()

Com

pres

sion

stren

gth

(kg

cm2)

y = 4969 minus 18797x R = 053944








0 5 10 15 20 250

10

20

30

40

50

60

70

80

Strain ()

Tens

ion

(KN

)











00

0050

010

015

020

0 1 2 3 4 5

Core 1Core 3Core 6


Chlo

ride c

onte

nt (

)

Depth (cm)


110

115

120

125

130

0 1 2 3 4 5

Core 1Core 3Core 9


pH

Depth (cm)











00

050

10

15

20

0 4 8 12 16pH

Corrosion

Corrosion

Passivation

Immunity

E(V

)

minus050

minus10

minus15








585540495450405360315270225180135904500


















119879119894(119862119900 119862th 119863 119889119888) =

119889119888

2






119900) has been



119863 = 10minus10+(466wc)

wc=27

1198911015840

cyl + 135

(2)




119889119888

(120583Acm2) (3)









119860119904(119879119900) =120587

4(119863119900minus 00232 times 119894corr119879119900)

2

(6)







Do









SF =120593119872119899(119879119900)

119872119906

gt 10 (7)

SF =120593119881119899(119879119900)

119881119906

gt 10 (8)



119906= flexural


119900




119872119899(119879119900) = 119860


119881119899(119879119900) =1


119860V (119879119900) times 119891119910 times 119889

119904 (10)


119900 119891119910=




02

04

06

08

10

12

14

16

1970 1980 1990 2000 2010 2020 2030 2040


Safe

ty fa

ctor

Year



119904(119879119900) and for





0500

100

150

200

250

300

1970 1980 1990 2000 2010 2020 2030 2040


Safe

ty fa

ctor

Year


0500

100

150

200

250

1970 1980 1990 2000 2010 2020 2030 2040


Safe

ty fa

ctor

Year




200

250

300

350

400

450

1970 1980 1990 2000 2010 2020 2030 2040


Safe

ty fa

ctor

Year




5 Conclusions









Acknowledgments


References























RoboticsJournal of





Journal of



RotatingMachinery





VLSI Design



Shock and Vibration







Journal of



Volume 2014


SensorsJournal of





Propagation










220

230

240

250

260

270

280


Com

pres

sion

stren

gth

(kg

cm2)

y = 14941 + 0040568x R = 099739


375

380

385

390

395

400

405

410


Com

pres

sion

stren

gth

(kg

cm2)

y = 35616 + 0015232x R = 032005



350

360

370

380

390

400


Com

pres

sion

stren

gth

(kg

cm2)

y = 50195 minus 0062572x R = 058026


29 30 31 32 33 34 35375

380

385

390

395

400

405

410

Rebound number

Com

pres

sion

stren

gth

(kg

cm2)

y = minus13465 + 011432x R = 072089





28 29 30 31 32 33 34 35200

250

300

350

400

450

Rebound number

Com

pres

sion

stren

gth

(kg

cm2)

y = 28479 + 00077793x R = 019884







200

250

300

350

400

450

4 5 6 7 8 9 10 11 12Porosity ()

Com

pres

sion

stren

gth

(kg

cm2)

y = 4969 minus 18797x R = 053944








0 5 10 15 20 250

10

20

30

40

50

60

70

80

Strain ()

Tens

ion

(KN

)











00

0050

010

015

020

0 1 2 3 4 5

Core 1Core 3Core 6


Chlo

ride c

onte

nt (

)

Depth (cm)


110

115

120

125

130

0 1 2 3 4 5

Core 1Core 3Core 9


pH

Depth (cm)











00

050

10

15

20

0 4 8 12 16pH

Corrosion

Corrosion

Passivation

Immunity

E(V

)

minus050

minus10

minus15








585540495450405360315270225180135904500


















119879119894(119862119900 119862th 119863 119889119888) =

119889119888

2






119900) has been



119863 = 10minus10+(466wc)

wc=27

1198911015840

cyl + 135

(2)




119889119888

(120583Acm2) (3)









119860119904(119879119900) =120587

4(119863119900minus 00232 times 119894corr119879119900)

2

(6)







Do









SF =120593119872119899(119879119900)

119872119906

gt 10 (7)

SF =120593119881119899(119879119900)

119881119906

gt 10 (8)



119906= flexural


119900




119872119899(119879119900) = 119860


119881119899(119879119900) =1


119860V (119879119900) times 119891119910 times 119889

119904 (10)


119900 119891119910=




02

04

06

08

10

12

14

16

1970 1980 1990 2000 2010 2020 2030 2040


Safe

ty fa

ctor

Year



119904(119879119900) and for





0500

100

150

200

250

300

1970 1980 1990 2000 2010 2020 2030 2040


Safe

ty fa

ctor

Year


0500

100

150

200

250

1970 1980 1990 2000 2010 2020 2030 2040


Safe

ty fa

ctor

Year




200

250

300

350

400

450

1970 1980 1990 2000 2010 2020 2030 2040


Safe

ty fa

ctor

Year




5 Conclusions









Acknowledgments


References























RoboticsJournal of





Journal of



RotatingMachinery





VLSI Design



Shock and Vibration







Journal of



Volume 2014


SensorsJournal of





Propagation










28 29 30 31 32 33 34 35200

250

300

350

400

450

Rebound number

Com

pres

sion

stren

gth

(kg

cm2)

y = 28479 + 00077793x R = 019884







200

250

300

350

400

450

4 5 6 7 8 9 10 11 12Porosity ()

Com

pres

sion

stren

gth

(kg

cm2)

y = 4969 minus 18797x R = 053944








0 5 10 15 20 250

10

20

30

40

50

60

70

80

Strain ()

Tens

ion

(KN

)











00

0050

010

015

020

0 1 2 3 4 5

Core 1Core 3Core 6


Chlo

ride c

onte

nt (

)

Depth (cm)


110

115

120

125

130

0 1 2 3 4 5

Core 1Core 3Core 9


pH

Depth (cm)











00

050

10

15

20

0 4 8 12 16pH

Corrosion

Corrosion

Passivation

Immunity

E(V

)

minus050

minus10

minus15








585540495450405360315270225180135904500


















119879119894(119862119900 119862th 119863 119889119888) =

119889119888

2






119900) has been



119863 = 10minus10+(466wc)

wc=27

1198911015840

cyl + 135

(2)




119889119888

(120583Acm2) (3)









119860119904(119879119900) =120587

4(119863119900minus 00232 times 119894corr119879119900)

2

(6)







Do









SF =120593119872119899(119879119900)

119872119906

gt 10 (7)

SF =120593119881119899(119879119900)

119881119906

gt 10 (8)



119906= flexural


119900




119872119899(119879119900) = 119860


119881119899(119879119900) =1


119860V (119879119900) times 119891119910 times 119889

119904 (10)


119900 119891119910=




02

04

06

08

10

12

14

16

1970 1980 1990 2000 2010 2020 2030 2040


Safe

ty fa

ctor

Year



119904(119879119900) and for





0500

100

150

200

250

300

1970 1980 1990 2000 2010 2020 2030 2040


Safe

ty fa

ctor

Year


0500

100

150

200

250

1970 1980 1990 2000 2010 2020 2030 2040


Safe

ty fa

ctor

Year




200

250

300

350

400

450

1970 1980 1990 2000 2010 2020 2030 2040


Safe

ty fa

ctor

Year




5 Conclusions









Acknowledgments


References























RoboticsJournal of





Journal of



RotatingMachinery





VLSI Design



Shock and Vibration







Journal of



Volume 2014


SensorsJournal of





Propagation












0 5 10 15 20 250

10

20

30

40

50

60

70

80

Strain ()

Tens

ion

(KN

)











00

0050

010

015

020

0 1 2 3 4 5

Core 1Core 3Core 6


Chlo

ride c

onte

nt (

)

Depth (cm)


110

115

120

125

130

0 1 2 3 4 5

Core 1Core 3Core 9


pH

Depth (cm)











00

050

10

15

20

0 4 8 12 16pH

Corrosion

Corrosion

Passivation

Immunity

E(V

)

minus050

minus10

minus15








585540495450405360315270225180135904500


















119879119894(119862119900 119862th 119863 119889119888) =

119889119888

2






119900) has been



119863 = 10minus10+(466wc)

wc=27

1198911015840

cyl + 135

(2)




119889119888

(120583Acm2) (3)









119860119904(119879119900) =120587

4(119863119900minus 00232 times 119894corr119879119900)

2

(6)







Do









SF =120593119872119899(119879119900)

119872119906

gt 10 (7)

SF =120593119881119899(119879119900)

119881119906

gt 10 (8)



119906= flexural


119900




119872119899(119879119900) = 119860


119881119899(119879119900) =1


119860V (119879119900) times 119891119910 times 119889

119904 (10)


119900 119891119910=




02

04

06

08

10

12

14

16

1970 1980 1990 2000 2010 2020 2030 2040


Safe

ty fa

ctor

Year



119904(119879119900) and for





0500

100

150

200

250

300

1970 1980 1990 2000 2010 2020 2030 2040


Safe

ty fa

ctor

Year


0500

100

150

200

250

1970 1980 1990 2000 2010 2020 2030 2040


Safe

ty fa

ctor

Year




200

250

300

350

400

450

1970 1980 1990 2000 2010 2020 2030 2040


Safe

ty fa

ctor

Year




5 Conclusions









Acknowledgments


References























RoboticsJournal of





Journal of



RotatingMachinery





VLSI Design



Shock and Vibration







Journal of



Volume 2014


SensorsJournal of





Propagation










00

0050

010

015

020

0 1 2 3 4 5

Core 1Core 3Core 6


Chlo

ride c

onte

nt (

)

Depth (cm)


110

115

120

125

130

0 1 2 3 4 5

Core 1Core 3Core 9


pH

Depth (cm)











00

050

10

15

20

0 4 8 12 16pH

Corrosion

Corrosion

Passivation

Immunity

E(V

)

minus050

minus10

minus15








585540495450405360315270225180135904500


















119879119894(119862119900 119862th 119863 119889119888) =

119889119888

2






119900) has been



119863 = 10minus10+(466wc)

wc=27

1198911015840

cyl + 135

(2)




119889119888

(120583Acm2) (3)









119860119904(119879119900) =120587

4(119863119900minus 00232 times 119894corr119879119900)

2

(6)







Do









SF =120593119872119899(119879119900)

119872119906

gt 10 (7)

SF =120593119881119899(119879119900)

119881119906

gt 10 (8)



119906= flexural


119900




119872119899(119879119900) = 119860


119881119899(119879119900) =1


119860V (119879119900) times 119891119910 times 119889

119904 (10)


119900 119891119910=




02

04

06

08

10

12

14

16

1970 1980 1990 2000 2010 2020 2030 2040


Safe

ty fa

ctor

Year



119904(119879119900) and for





0500

100

150

200

250

300

1970 1980 1990 2000 2010 2020 2030 2040


Safe

ty fa

ctor

Year


0500

100

150

200

250

1970 1980 1990 2000 2010 2020 2030 2040


Safe

ty fa

ctor

Year




200

250

300

350

400

450

1970 1980 1990 2000 2010 2020 2030 2040


Safe

ty fa

ctor

Year




5 Conclusions









Acknowledgments


References























RoboticsJournal of





Journal of



RotatingMachinery





VLSI Design



Shock and Vibration







Journal of



Volume 2014


SensorsJournal of





Propagation










00

050

10

15

20

0 4 8 12 16pH

Corrosion

Corrosion

Passivation

Immunity

E(V

)

minus050

minus10

minus15








585540495450405360315270225180135904500


















119879119894(119862119900 119862th 119863 119889119888) =

119889119888

2






119900) has been



119863 = 10minus10+(466wc)

wc=27

1198911015840

cyl + 135

(2)




119889119888

(120583Acm2) (3)









119860119904(119879119900) =120587

4(119863119900minus 00232 times 119894corr119879119900)

2

(6)







Do









SF =120593119872119899(119879119900)

119872119906

gt 10 (7)

SF =120593119881119899(119879119900)

119881119906

gt 10 (8)



119906= flexural


119900




119872119899(119879119900) = 119860


119881119899(119879119900) =1


119860V (119879119900) times 119891119910 times 119889

119904 (10)


119900 119891119910=




02

04

06

08

10

12

14

16

1970 1980 1990 2000 2010 2020 2030 2040


Safe

ty fa

ctor

Year



119904(119879119900) and for





0500

100

150

200

250

300

1970 1980 1990 2000 2010 2020 2030 2040


Safe

ty fa

ctor

Year


0500

100

150

200

250

1970 1980 1990 2000 2010 2020 2030 2040


Safe

ty fa

ctor

Year




200

250

300

350

400

450

1970 1980 1990 2000 2010 2020 2030 2040


Safe

ty fa

ctor

Year




5 Conclusions









Acknowledgments


References























RoboticsJournal of





Journal of



RotatingMachinery





VLSI Design



Shock and Vibration







Journal of



Volume 2014


SensorsJournal of





Propagation




















119879119894(119862119900 119862th 119863 119889119888) =

119889119888

2






119900) has been



119863 = 10minus10+(466wc)

wc=27

1198911015840

cyl + 135

(2)




119889119888

(120583Acm2) (3)









119860119904(119879119900) =120587

4(119863119900minus 00232 times 119894corr119879119900)

2

(6)







Do









SF =120593119872119899(119879119900)

119872119906

gt 10 (7)

SF =120593119881119899(119879119900)

119881119906

gt 10 (8)



119906= flexural


119900




119872119899(119879119900) = 119860


119881119899(119879119900) =1


119860V (119879119900) times 119891119910 times 119889

119904 (10)


119900 119891119910=




02

04

06

08

10

12

14

16

1970 1980 1990 2000 2010 2020 2030 2040


Safe

ty fa

ctor

Year



119904(119879119900) and for





0500

100

150

200

250

300

1970 1980 1990 2000 2010 2020 2030 2040


Safe

ty fa

ctor

Year


0500

100

150

200

250

1970 1980 1990 2000 2010 2020 2030 2040


Safe

ty fa

ctor

Year




200

250

300

350

400

450

1970 1980 1990 2000 2010 2020 2030 2040


Safe

ty fa

ctor

Year




5 Conclusions









Acknowledgments


References























RoboticsJournal of





Journal of



RotatingMachinery





VLSI Design



Shock and Vibration







Journal of



Volume 2014


SensorsJournal of





Propagation












Do









SF =120593119872119899(119879119900)

119872119906

gt 10 (7)

SF =120593119881119899(119879119900)

119881119906

gt 10 (8)



119906= flexural


119900




119872119899(119879119900) = 119860


119881119899(119879119900) =1


119860V (119879119900) times 119891119910 times 119889

119904 (10)


119900 119891119910=




02

04

06

08

10

12

14

16

1970 1980 1990 2000 2010 2020 2030 2040


Safe

ty fa

ctor

Year



119904(119879119900) and for





0500

100

150

200

250

300

1970 1980 1990 2000 2010 2020 2030 2040


Safe

ty fa

ctor

Year


0500

100

150

200

250

1970 1980 1990 2000 2010 2020 2030 2040


Safe

ty fa

ctor

Year




200

250

300

350

400

450

1970 1980 1990 2000 2010 2020 2030 2040


Safe

ty fa

ctor

Year




5 Conclusions









Acknowledgments


References























RoboticsJournal of





Journal of



RotatingMachinery





VLSI Design



Shock and Vibration







Journal of



Volume 2014


SensorsJournal of





Propagation










02

04

06

08

10

12

14

16

1970 1980 1990 2000 2010 2020 2030 2040


Safe

ty fa

ctor

Year



119904(119879119900) and for





0500

100

150

200

250

300

1970 1980 1990 2000 2010 2020 2030 2040


Safe

ty fa

ctor

Year


0500

100

150

200

250

1970 1980 1990 2000 2010 2020 2030 2040


Safe

ty fa

ctor

Year




200

250

300

350

400

450

1970 1980 1990 2000 2010 2020 2030 2040


Safe

ty fa

ctor

Year




5 Conclusions









Acknowledgments


References























RoboticsJournal of





Journal of



RotatingMachinery





VLSI Design



Shock and Vibration







Journal of



Volume 2014


SensorsJournal of





Propagation










200

250

300

350

400

450

1970 1980 1990 2000 2010 2020 2030 2040


Safe

ty fa

ctor

Year




5 Conclusions









Acknowledgments


References























RoboticsJournal of





Journal of



RotatingMachinery





VLSI Design



Shock and Vibration







Journal of



Volume 2014


SensorsJournal of





Propagation






























RoboticsJournal of





Journal of



RotatingMachinery





VLSI Design



Shock and Vibration







Journal of



Volume 2014


SensorsJournal of





Propagation









case study of remaining service life assessment of a cooling

Documents