A three-phase, multi-component ionic transport model for simulation of chloride penetration in concrete

A numerical study on chloride migration in cracked concrete using multi-component ionic transport models

“…Their study also showed that the chloride binding by the Above numerical studies considered a diffusion problem and employed the Fick's second law to govern the chloride penetration in cracked concrete. In view of the long duration of diffusion tests and the need of electrochemical rehabilitation, the action of externally applied electric field is prevalently involved in a bunch of numerical models of chloride transport in concrete [27][28][29][30][31][32][33][34][35][36][37][38][39][40][41]. These models extended the ionic diffusion to a more complicated migration dominated process, which follows the applications of the rapid chloride migration (RCM) test [42][43][44] and the electrochemical chloride removal/extraction (ECR/ECE) treatment [45].…”

Influence of axial loads on CO2 and Cl− transport in concrete phases: Paste, mortar and ITZ

“…Considering the effect of ionic exchange between pores of different sizes, ionic binding between liquid and 90 solid phases and the boundary-layer effect of the exposed surface on chloride transport, Li et al [23] presented 91 a new transport model to evaluate the penetration of Clinto concrete. Liu et al [24] proposed a three-phase 92 transport model to simulate chloride penetration in concrete in which they also considered the effect of multi-93 component ionic. The above mentioned simulation models have been established or improved based on 94 experimental data obtained from Cltransport tests, while few of them has considered the influence of external 95 loads on the detailed transport process of Clwithin the concrete.…”

“…First of all, 5% CO2 environment was 277 selected for the carbonation exposure in this study, whereas for the Clingress test, 165 g/L NaCl solution was 278 used. Secondly, phenolphthalein was used for testing the depth of carbonation, which specifies a pH of 9 as 279 the threshold value between carbonated and uncarbonated samples, and the measured depth must be 280 theoretically lower than the true carbonation depth [24] . In contrast, the Clingress depth is tested by the AgNO3 281 solution, which can identify the location with a Clconcentration of 0.01%-0.4% by mass of the cementitious 282 material [37] , which can basically be considered as the true Clingress depth.…”

Modelling of solid formation by heterogeneous reactions through a multicomponent transport model of diluted ionic species: Simulation of barite fouling in a geothermal heat exchanger

“…We note that electroneutrality and obviously i = 0 is no longer valid hypothesis in applications with externally applied electric field. This is the case for example at the vicinity of electrodes in migration experiments . The electric potential is then determined using Poisson's equation which replaces the electroneutrality condition …”