الفهرس 
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Abstract
The present Investigation aims to !’tudy efficiency of (he electrochemicaJ proc.e$$ oo
ext:raction of chlorides from reinforced concrete slabs. It also, includes the investigation of
different factora influence the electN.’!chemical chloride extraction, and the eff«1: of the
proeess on the properties of concrete and remforccmenL
In order to achieve this aim of study twenty two slabs oonrain various amounts of chlorides
derived from sodium chloride were cast The slabs were divided into four groups acoordi.ng to
chlorides eontenl;
group ( A ) contains 4 % , group { H ) contuins 2 % , group ( C ) contains I %, group (D)
contains 0.5% (weight% of cement contem}.
Different W:tors have been taken into consideration in this study such as difference in
concrete cover thickness, difference in current dcn~itics, difference in inlcmal steel mesh
(cathode) and difference in external steel mesh (anode). Also the effect of electrochemical
process on the properties of reinforced concrete such as strength, the bond between concrete
and steel were investigated • The results indic:ne that
Electrocbemlcal chloride extraction is a feasible tech.’lique for the rettabilitation of reinforced
ooncrete structures with chloride induced eorrosion, about 40 w 70 % of the chlorides were
removed on avttage. repassivation of the rebars is fpcililatcd by the increASe in alkalinity at
the surface of the sleet However the ~hloride content w.;re removed by 50%~ 88 %around
reinf~t.The efficiency of the system depends on concrete cover, cunent density and
chloride ions ooneentralion in concrete. At !ow cover where the anode mesh is near to the
c.a.thode mesb ( rei:nfurcement ) good extraction for chlorides from reinfon:cd concrete will
occur . Increasing current density leads to increase the rate and the percentage of extraction .
l.ncre:asing the distance between the cathode ( reinforcement ) and the anode leads to low
extmction along the depth of slabs and unequal extraction around reinforcement.Socood
treatment after several months may be required to re~ove originally compound chlorides.
For the limited range of specimens studied, no significant changes in tbe properties of
concrete ( compressive strength , density, bond strength and steel properties) due to the
eledrochemieaJ. cbloride extr~tion .