REVISTA
CONSTRU
CHEMICAL
43
artigo técnico
Figura6–Vergalhões removidos de cilindros de
concretodepois de quatroanos.Os dois primeiros
sãode referência, odomeio, foi retiradode concreto
comadiçãode 2%deNC e o inferior com4%deNC
(CN em inglês).
BALONIS eoutros (2011) [3] investigaramo efeitodapre-
sença deNC e nitritode cálcionoprocessode hidrataçãodo
cimento. Eles descobriram que oNC émais forte diluído na
matrizdoconcreto, alémdesereliminadode formamais lenta,
em comparação comonitrito.A razãodo efeitomais lentode
eliminaçãodoNCemcomparaçãocomonitrito sedevea sua
reaçãocinéticamais lenta, comomostradoporAl-MEHTHEL
eoutros(2009)[1],porémosresultadospositivosdosensaiosde
longoprazosãomais importantes, jáqueacorrosão,naprática,
éumprocesso lento.
CONCLUSÕES
ONC(nitratodecálcio)éumaditivoparaconcretoquepode
desempenhar as seguintes funções: 1) Acelerador, 2) Contra-
atacaroretardodosplastificantesenquantomantémareologia,
3)Aumentodaresistêncianolongoprazo,4)Anticongelamento
ouaditivopara invernoe5) Inibidor contracorrosão induzida
porcloretosnosvergalhões.
Assim, é justocaracterizaroNCcomoumaditivomultifun-
cionalparaoconcreto.
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