Electric current-induced changes in porosity and Chloride resistance of hardened concrete

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68407700%3A21110%2F25%3A00386839" target="_blank" >RIV/68407700:21110/25:00386839 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/60461373:22310/25:43933581

Výsledek na webu

<a href="https://doi.org/10.1016/j.jobe.2025.113867" target="_blank" >https://doi.org/10.1016/j.jobe.2025.113867</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.jobe.2025.113867" target="_blank" >10.1016/j.jobe.2025.113867</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Electric current-induced changes in porosity and Chloride resistance of hardened concrete

Popis výsledku v původním jazyce

This study demonstrates that direct current (DC) treatments can significantly alter the microstructure, porosity, and chloride resistance of cement-based concretes and mortars, including pure Portland cement as well as limestone- and microsilica-blended cements. A combination of experimental techniques — gravimetry, scanning electron microscopy (SEM) image analysis, mercury intrusion porosimetry (MIP), electrochemical impedance spectroscopy (EIS), and chloride penetration tests — was employed to evaluate changes in microstructure and transport properties. The results reveal that DC treatment significantly increases open porosity, especially in pure Portland cement systems (11%–17%), compared to blended systems (5%–9%). EIS measurements corroborated these findings, showing decreased resistance in DC-treated samples. Image analysis confirmed increased porosity, predominantly localized in the interfacial transition zones around aggregates, where hydration products such as calcium hydroxide (CH) were more susceptible to leaching. MIP measurements indicated a shift towards smaller pores ( 0.1 µm), at the expense of medium-sized capillary pores (0.1–1 µm). Chloride penetration tests revealed increased diffusion coefficients in pure Portland cement systems, correlating with higher porosity. However, samples with microsilica admixtures demonstrated enhanced chloride resistance, attributed to the higher packing density and higher Calcium-Silica-Hydrates (C-S-H) content resulting from microsilica–CH reactions and to the chloride binding. While smaller quantities of chloride ingress were observed, deeper penetration due to increased diffusion coefficients presents risks for rebar corrosion in reinforced concrete structures. These findings provide insights into the mechanisms governing microstructural changes under DC exposure and their role in chloride transport.

Název v anglickém jazyce

Electric current-induced changes in porosity and Chloride resistance of hardened concrete

Popis výsledku anglicky

This study demonstrates that direct current (DC) treatments can significantly alter the microstructure, porosity, and chloride resistance of cement-based concretes and mortars, including pure Portland cement as well as limestone- and microsilica-blended cements. A combination of experimental techniques — gravimetry, scanning electron microscopy (SEM) image analysis, mercury intrusion porosimetry (MIP), electrochemical impedance spectroscopy (EIS), and chloride penetration tests — was employed to evaluate changes in microstructure and transport properties. The results reveal that DC treatment significantly increases open porosity, especially in pure Portland cement systems (11%–17%), compared to blended systems (5%–9%). EIS measurements corroborated these findings, showing decreased resistance in DC-treated samples. Image analysis confirmed increased porosity, predominantly localized in the interfacial transition zones around aggregates, where hydration products such as calcium hydroxide (CH) were more susceptible to leaching. MIP measurements indicated a shift towards smaller pores ( 0.1 µm), at the expense of medium-sized capillary pores (0.1–1 µm). Chloride penetration tests revealed increased diffusion coefficients in pure Portland cement systems, correlating with higher porosity. However, samples with microsilica admixtures demonstrated enhanced chloride resistance, attributed to the higher packing density and higher Calcium-Silica-Hydrates (C-S-H) content resulting from microsilica–CH reactions and to the chloride binding. While smaller quantities of chloride ingress were observed, deeper penetration due to increased diffusion coefficients presents risks for rebar corrosion in reinforced concrete structures. These findings provide insights into the mechanisms governing microstructural changes under DC exposure and their role in chloride transport.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

20101 - Civil engineering

Projekt

<a href="/cs/project/GA23-05435S" target="_blank" >GA23-05435S: Účinky radiačního působení na nanomechanické vlastnosti cementových kompozitů v proměnných podmínkách prostředí</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2025

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Journal of Building Engineering

ISSN

2352-7102

e-ISSN

2352-7102

Svazek periodika

112

Číslo periodika v rámci svazku

October

Stát vydavatele periodika

GB - Spojené království Velké Británie a Severního Irska

Počet stran výsledku

19

Strana od-do

—

Kód UT WoS článku

001569209600022

EID výsledku v databázi Scopus

2-s2.0-105014929312