Numerical and Experimental Analysis of Self-Protection in Reinforced Concrete due to Application of Mg-Al-NO(2)Layered Double Hydroxides

authors	Mir, ZM; Bastos, A; Gomes, C; Mueller, U; Alonso, MC; Villar, K; Rabade, MP; Maia, F; Rocha, CM; Maincon, P; Hoche, D; Ferreira, MGS; Zheludkevich, ML
nationality	International
journal	ADVANCED ENGINEERING MATERIALS
author keywords	concrete; corrosion; finite element analysis; layered double hydroxides
keywords	LAYERED DOUBLE HYDROXIDES; CHLORIDE BINDING-CAPACITY; CARBON-STEEL; IONIC TRANSPORT; CORROSION; MARINE; PROFILES; PRODUCTS; MODEL; SCALE
abstract	Concrete possesses an intrinsic chloride binding capacity. Chloride ions from the environment bind with the hydrated cementitious phases in the form of bound chlorides. The contribution of chemically bound chlorides toward increasing the service life of concrete structures is vital as they help in slowing down the chloride diffusion in the concrete thereby delaying reinforcement depassivation. The authors attempt to increase the chloride binding capacity of concrete by adding a small amount of Mg-Al-NO(2)layered double hydroxides (LDHs) with the objective to delay reinforcement corrosion and by this to considerably extend the service life of concrete structures situated in harsh environments. This study presents numerical and experimental analysis of the action of LDH in concrete. Formation factor is used to determine the effective chloride diffusion coefficient. In addition, the chloride binding isotherms together with Poisson-Nernst-Planck equations are used to model the chloride ingress. A comparable chloride binding is observed for concrete with and without Mg-Al-NO2, depicting only a slight chloride uptake by Mg-Al-NO2. Further investigations are conducted to understand this behavior by studying the stability and chloride entrapping capacity Mg-Al-NO(2)in concrete.
publisher	WILEY-V C H VERLAG GMBH
issn	1438-1656
isbn	1527-2648
year published	2020
volume	22
issue	11
digital object identifier (doi)	10.1002/adem.202000398
web of science category	Materials Science, Multidisciplinary
subject category	Materials Science
unique article identifier	WOS:000541483900001