Chloride Ion Diffusion Resistance of Bulk Hydrophobic Concrete: Comparison of w/c and Dosages
Post-cast application of hydrophobic agents onto hardened concrete is successful at reducing external ion diffusion into cement paste, this work examines pre-cast application of hydrophobic admixtures in fresh concrete. Concretes, with water to cement ratios (w/c) 0.45 and 0.50 (CEM I; low C3A), wer...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
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Sciendo
2023-07-01
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| Series: | Nordic Concrete Research |
| Subjects: | |
| Online Access: | https://doi.org/10.2478/ncr-2022-0020 |
| _version_ | 1797682317915848704 |
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| author | Rogers Patrick Silfwerbrand Johan Selander Anders Trägårdh Jan Utgenannt Peter |
| author_facet | Rogers Patrick Silfwerbrand Johan Selander Anders Trägårdh Jan Utgenannt Peter |
| author_sort | Rogers Patrick |
| collection | DOAJ |
| description | Post-cast application of hydrophobic agents onto hardened concrete is successful at reducing external ion diffusion into cement paste, this work examines pre-cast application of hydrophobic admixtures in fresh concrete. Concretes, with water to cement ratios (w/c) 0.45 and 0.50 (CEM I; low C3A), were mixed. Adding alkyltrialkoxysilane or triacylglycerol admixtures ranging from 1 to 3 wt%cem in these concretes were evaluated. Increasing the dosage of hydrophobic admixtures decreased the compressive strength. The usage of these admixtures did not hinder the further development of the microstructure as all concretes gained strength after one year, but not in the same percentage increase as the reference concrete. Chloride ion diffusion, after exposure to 3 wt% NaCl solution at 20 °C for 91 days, in concretes with 1 wt%cem admixture showed slight reductions in diffusion rate (8-17%) compared to the reference. At 3 wt%cem, triacylglycerol admixtures showed better hindering effects of inward chloride diffusion, this was especially evident in w/c = 0.45. Equivalent addition of alkyltrialkoxysilane-based admixtures increased the diffusion of chloride ions transferred into the cement matrix. |
| first_indexed | 2024-03-11T23:57:57Z |
| format | Article |
| id | doaj.art-317792cb53f0468db4802796fbbe4dbd |
| institution | Directory Open Access Journal |
| issn | 2545-2819 |
| language | English |
| last_indexed | 2024-03-11T23:57:57Z |
| publishDate | 2023-07-01 |
| publisher | Sciendo |
| record_format | Article |
| series | Nordic Concrete Research |
| spelling | doaj.art-317792cb53f0468db4802796fbbe4dbd2023-09-18T06:33:31ZengSciendoNordic Concrete Research2545-28192023-07-01681173810.2478/ncr-2022-0020Chloride Ion Diffusion Resistance of Bulk Hydrophobic Concrete: Comparison of w/c and DosagesRogers Patrick0Silfwerbrand Johan1Selander Anders2Trägårdh Jan3Utgenannt Peter41Licentiate of Philosophy, Weber Saint-Gobain AB, Pålamalmsvägen 60, SE-146 33 Tullinge, Sweden2PhD, Professor, KTH Royal Institute of Technology, Dept. of Civil & Architectural Engineering, Brinellvägen 23, SE-100 44Stockholm, Sweden3PhD, Heidelberg Materials Cement Sweden, Marieviksgatan 25, SE-100 74Stockholm4Licentiate of Philosophy, Consultant, Grycksbovägen 51, SE-12247Enskede5PhD, Department Manager, Havsfiskelaboratoriet / SLU-Aqua, SE-453 30LysekilPost-cast application of hydrophobic agents onto hardened concrete is successful at reducing external ion diffusion into cement paste, this work examines pre-cast application of hydrophobic admixtures in fresh concrete. Concretes, with water to cement ratios (w/c) 0.45 and 0.50 (CEM I; low C3A), were mixed. Adding alkyltrialkoxysilane or triacylglycerol admixtures ranging from 1 to 3 wt%cem in these concretes were evaluated. Increasing the dosage of hydrophobic admixtures decreased the compressive strength. The usage of these admixtures did not hinder the further development of the microstructure as all concretes gained strength after one year, but not in the same percentage increase as the reference concrete. Chloride ion diffusion, after exposure to 3 wt% NaCl solution at 20 °C for 91 days, in concretes with 1 wt%cem admixture showed slight reductions in diffusion rate (8-17%) compared to the reference. At 3 wt%cem, triacylglycerol admixtures showed better hindering effects of inward chloride diffusion, this was especially evident in w/c = 0.45. Equivalent addition of alkyltrialkoxysilane-based admixtures increased the diffusion of chloride ions transferred into the cement matrix.https://doi.org/10.2478/ncr-2022-0020admixturesalkyl trialkoxysilaneschloride diffusionconcretehydrophobicsilanetriacylglycerolvegetable oil |
| spellingShingle | Rogers Patrick Silfwerbrand Johan Selander Anders Trägårdh Jan Utgenannt Peter Chloride Ion Diffusion Resistance of Bulk Hydrophobic Concrete: Comparison of w/c and Dosages Nordic Concrete Research admixtures alkyl trialkoxysilanes chloride diffusion concrete hydrophobic silane triacylglycerol vegetable oil |
| title | Chloride Ion Diffusion Resistance of Bulk Hydrophobic Concrete: Comparison of w/c and Dosages |
| title_full | Chloride Ion Diffusion Resistance of Bulk Hydrophobic Concrete: Comparison of w/c and Dosages |
| title_fullStr | Chloride Ion Diffusion Resistance of Bulk Hydrophobic Concrete: Comparison of w/c and Dosages |
| title_full_unstemmed | Chloride Ion Diffusion Resistance of Bulk Hydrophobic Concrete: Comparison of w/c and Dosages |
| title_short | Chloride Ion Diffusion Resistance of Bulk Hydrophobic Concrete: Comparison of w/c and Dosages |
| title_sort | chloride ion diffusion resistance of bulk hydrophobic concrete comparison of w c and dosages |
| topic | admixtures alkyl trialkoxysilanes chloride diffusion concrete hydrophobic silane triacylglycerol vegetable oil |
| url | https://doi.org/10.2478/ncr-2022-0020 |
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