-
8/19/2019 CE11M091
1/15
FINITE ELEMENT MODELLING OFCORROSION IN RC STRUCTURES
EXPOSED TO CHLORIDES
NIKHIL ATHALEKAR
CE11M091
STRUCTURAL ENGINEERING DIVISIONDEPARTMENT OF CIVIL ENGINEERING
INDIAN INSTITUTE OF TECHNOLOGY MADRAS
-
8/19/2019 CE11M091
2/15
Contents
Introduction Literture re!ie" O#$ecti!e % Sco&e Met'odo(o)* +or, done % its !(idtion Furt'er "or, % ti-e .r-e Re.erences
-
8/19/2019 CE11M091
3/15
Introduction
Structur( e/ects o. corrosion Corrosion is t"o st)e &rocess !i01 Initition
2c'(oride trns&ort3 % &ro&)tion 2cti!ecorrosion3
Mode((in) o. c'(oride trns&ort4 E/ect o. -oisture5u6 % te-&erture on c'(oride di/usion reconsidered
Go!ernin) PDE "s so(!ed s 7VP in s&ce % sIVP in ti-e #* -ens o. t"o di-ension( 8nitee(e-ent .or-u(tions usin) G(er,in -et'od
Pro)r--in) "s done in MATLA7
-
8/19/2019 CE11M091
4/15
Literture re!ie"
T'e -ec'nis- o. corrosion is t"o st)e &rocess2Tuutti9:;
-
8/19/2019 CE11M091
5/15
Process of corrosion (Tuutti,1982)
-
8/19/2019 CE11M091
6/15
Literture re!ie"
T'e sur.ce te-&erture cn #essu-ed e>u( to t'e en!iron-ent(te-&erture 27C in s&ce3 )i!en #*9
T'e te-&erture distri#ution in concrete-ust .o((o" in&ut te-&erture
distri#ution i1e1 Sinusoid( 2C'en %M'de!n9=
-
8/19/2019 CE11M091
7/15
O#$ecti!e % Sco&e
To de!e(o& )ener(ised co-&uter -ode( .or t'e&rediction o. ser!ice (i.e o. rein.orced concretestructures e6&osed to c'(orides
T'e sco&e o. t'is stud* is (i-ited to initition st)e o.
corrosion T'e -ode( is #sed on )ener( &'*sic( ("s so it
"ou(d not #e (i-ited to s&eci8c t*&e o. concrete oren!iron-ent( conditions
Concrete is ssu-ed uncrc,ed T'e i- o. t'is &ro$ect is to stud* t'e -ec'nis-
under(*in) t'e deteriortion &rocess o. rein.orcedconcrete ssocited "it' c'(oride induced corrosion
-
8/19/2019 CE11M091
8/15
Met'odo(o)*
To #e)in "it'4 Deter-intion o. te-&erturedistri#ution in concrete
Pro#(e-4
G(er,in -et'od "s used to con!ert t'isPDE into t"o di-ension( 8nite e(e-ent.or-u(tions
T'e resu(tin) s*ste- o. e>ution considerin)
contri#ution o. (( t'e e(e-ents is )i!en #*4
T'e do-in is discreti0ed s s'o"n in 8)ure
-
8/19/2019 CE11M091
9/15
-
8/19/2019 CE11M091
10/15
Met'odo(o)*
T'is e>ution re&resents s*ste- o.(iner 8rst order di/erenti( e>utions inti-e1 It is inte)rted in ti-e #* -ens o.
8nite di/erence &&ro6i-tion2se)er(ind9:;
-
8/19/2019 CE11M091
11/15
+or, done
T'e te-&erture distri#ution in concrete.o((o"s sinusoid( !rition
T'e resu(t cn #e !(idted #sed on t'e
.ct t't t'e out&ut te-&erturedistri#ution s'ou(d .o((o" in&utte-&erture !rition 2C'en %M'de!n9 =
-
8/19/2019 CE11M091
12/15
-
8/19/2019 CE11M091
13/15
Furt'er "or, % ti-e .r-e
No. Description of work Completion within
1. Solution of pore relative humidity Jan 2013
2. Calculating amount of evaporable water Feb 2013
3. Solution of concentration of chlorides dissolved in
the pore solution
Feb 2013
. Calculation of concentration of total chlorides !arch 2013
". #o chec$ if threshold value is reached% otherwise
increase total time & repeat
!arch 2013
'. (dditional wor$ & thesis writing (pril 2013
-
8/19/2019 CE11M091
14/15
Re.erences
Pere09 719 2:;;;39 Ser!ice (i.e -ode((in) o. RC 'i)'"* structures u'ui 'n)9 Moe M1 S1 C'eun) 2=:=39 Mode((in) o. c'(orideinduced corrosion
in rein.orced concrete structures9 Mteri(s % Structures Ferreir A11M19 MATLA7 codes .or 8nite e(e-ent n(*sis9 S&rin)er &u#(ictions
2=;3 C'en9 M'de!n9 2=
-
8/19/2019 CE11M091
15/15
THANK %&'