Maximilian Löher, Neven Ukrainczyk, Andreas Bogner, Astrid Hirsch, Frank Dehn, Eduardus Koenders
{"title":"Reactive transport modeling of acetic acid-induced degradation in portland cement paste","authors":"Maximilian Löher, Neven Ukrainczyk, Andreas Bogner, Astrid Hirsch, Frank Dehn, Eduardus Koenders","doi":"10.1016/j.cemconres.2024.107704","DOIUrl":null,"url":null,"abstract":"A reactive transport model was employed to investigate the influence of multiple hydrate phases during acetic acid attack on Portland cement paste. The simulation accounted for the dissolution of primary cement hydrates like Ettringite, Portlandite and C-S-H, along with the formation of silica gel products impacting diffusivity. The simulations primarily utilized independent material parameters, though the effective specific surface area of C-S-H phases required adjustment, indicating that only a small fraction is active in bulk paste compared to experimental values obtained from powders. Experiments involved exposing hardened cement paste samples to acetic acid (pH = 3) for durations ranging from 35 to 84 days. The model predicted changes in mineral assemblages, porosity, and pore solution chemistry versus degradation depth and time. Comparison of calculated Ca and Si-contents with experimentally obtained values from <span><math><mi is=\"true\">μ</mi></math></span>XRF analysis demonstrated good agreement of within 6% error, highlighting the importance of considering multiple minerals.","PeriodicalId":266,"journal":{"name":"Cement and Concrete Research","volume":null,"pages":null},"PeriodicalIF":10.9000,"publicationDate":"2024-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Cement and Concrete Research","FirstCategoryId":"5","ListUrlMain":"https://doi.org/10.1016/j.cemconres.2024.107704","RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"CONSTRUCTION & BUILDING TECHNOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
A reactive transport model was employed to investigate the influence of multiple hydrate phases during acetic acid attack on Portland cement paste. The simulation accounted for the dissolution of primary cement hydrates like Ettringite, Portlandite and C-S-H, along with the formation of silica gel products impacting diffusivity. The simulations primarily utilized independent material parameters, though the effective specific surface area of C-S-H phases required adjustment, indicating that only a small fraction is active in bulk paste compared to experimental values obtained from powders. Experiments involved exposing hardened cement paste samples to acetic acid (pH = 3) for durations ranging from 35 to 84 days. The model predicted changes in mineral assemblages, porosity, and pore solution chemistry versus degradation depth and time. Comparison of calculated Ca and Si-contents with experimentally obtained values from XRF analysis demonstrated good agreement of within 6% error, highlighting the importance of considering multiple minerals.
期刊介绍:
Cement and Concrete Research is dedicated to publishing top-notch research on the materials science and engineering of cement, cement composites, mortars, concrete, and related materials incorporating cement or other mineral binders. The journal prioritizes reporting significant findings in research on the properties and performance of cementitious materials. It also covers novel experimental techniques, the latest analytical and modeling methods, examination and diagnosis of actual cement and concrete structures, and the exploration of potential improvements in materials.