Service Life Evaluation for RC Sewer Structure Repaired with Bacteria Mixed Coating: Through Probabilistic and Deterministic Method
Since a concrete structure exposed to a sulfate environment is subject to surface ion ingress that yields cracking due to concrete swelling, its service life evaluation with an engineering modeling is very important. In this paper, cementitious repair materials containing bacteria, <i>Rhodobac...
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2021-09-01
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author | Hyun-Sub Yoon Keun-Hyeok Yang Kwang-Myong Lee Seung-Jun Kwon |
author_facet | Hyun-Sub Yoon Keun-Hyeok Yang Kwang-Myong Lee Seung-Jun Kwon |
author_sort | Hyun-Sub Yoon |
collection | DOAJ |
description | Since a concrete structure exposed to a sulfate environment is subject to surface ion ingress that yields cracking due to concrete swelling, its service life evaluation with an engineering modeling is very important. In this paper, cementitious repair materials containing bacteria, <i>Rhodobacter capsulatus,</i> and porous spores for immobilization were developed, and the service life of RC (Reinforced Concrete) structures with a developed bacteria-coating was evaluated through deterministic and probabilistic methods. Design parameters such protective coating thickness, diffusion coefficient, surface roughness, and exterior sulfate ion concentration were considered, and the service life was evaluated with the changing mean and coefficient of variation (COV) of each factor. From service life evaluation, more conservative results were evaluated with the probabilistic method than the deterministic method, and as a result of the analysis, coating thickness and surface roughness were derived as key design parameters for ensuring service life. In an environment exposed to an exterior sulfate concentration of 200 ppm, using the deterministic method, the service life was 17.3 years without repair, 19.7 years with normal repair mortar, and 29.6 years with the application of bacteria-coating. Additionally, when the probabilistic method is applied in the same environment, the service life was changed to 9.2–16.0 years, 10.5–18.2 years, and 15.4–27.4 years, respectively, depending on the variation of design parameters. The developed bacteria-coating technique showed a 1.47–1.50 times higher service life than the application of normal repair mortar, and the effect was much improved when it had a low COV of around 0.1. |
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issn | 1996-1944 |
language | English |
last_indexed | 2024-03-10T07:28:59Z |
publishDate | 2021-09-01 |
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spelling | doaj.art-68e610991c49435f923f322f90c7f5782023-11-22T14:03:52ZengMDPI AGMaterials1996-19442021-09-011418542410.3390/ma14185424Service Life Evaluation for RC Sewer Structure Repaired with Bacteria Mixed Coating: Through Probabilistic and Deterministic MethodHyun-Sub Yoon0Keun-Hyeok Yang1Kwang-Myong Lee2Seung-Jun Kwon3Department of Architectural Engineering, Kyonggi University, Suwon 16227, KoreaDepartment of Architectural Engineering, Kyonggi University, Suwon 16227, KoreaDepartment of Civil, Architectural and Environmental System Engineering, Sungkyunkwan University, Suwon 16419, KoreaDepartment of Civil and Environmental Engineering, Hannam University, Daejeon 34430, KoreaSince a concrete structure exposed to a sulfate environment is subject to surface ion ingress that yields cracking due to concrete swelling, its service life evaluation with an engineering modeling is very important. In this paper, cementitious repair materials containing bacteria, <i>Rhodobacter capsulatus,</i> and porous spores for immobilization were developed, and the service life of RC (Reinforced Concrete) structures with a developed bacteria-coating was evaluated through deterministic and probabilistic methods. Design parameters such protective coating thickness, diffusion coefficient, surface roughness, and exterior sulfate ion concentration were considered, and the service life was evaluated with the changing mean and coefficient of variation (COV) of each factor. From service life evaluation, more conservative results were evaluated with the probabilistic method than the deterministic method, and as a result of the analysis, coating thickness and surface roughness were derived as key design parameters for ensuring service life. In an environment exposed to an exterior sulfate concentration of 200 ppm, using the deterministic method, the service life was 17.3 years without repair, 19.7 years with normal repair mortar, and 29.6 years with the application of bacteria-coating. Additionally, when the probabilistic method is applied in the same environment, the service life was changed to 9.2–16.0 years, 10.5–18.2 years, and 15.4–27.4 years, respectively, depending on the variation of design parameters. The developed bacteria-coating technique showed a 1.47–1.50 times higher service life than the application of normal repair mortar, and the effect was much improved when it had a low COV of around 0.1.https://www.mdpi.com/1996-1944/14/18/5424<i>Rhodobacter capsulatus</i>sewage concretesurface coatingsulfate ionservice lifecover depth |
spellingShingle | Hyun-Sub Yoon Keun-Hyeok Yang Kwang-Myong Lee Seung-Jun Kwon Service Life Evaluation for RC Sewer Structure Repaired with Bacteria Mixed Coating: Through Probabilistic and Deterministic Method Materials <i>Rhodobacter capsulatus</i> sewage concrete surface coating sulfate ion service life cover depth |
title | Service Life Evaluation for RC Sewer Structure Repaired with Bacteria Mixed Coating: Through Probabilistic and Deterministic Method |
title_full | Service Life Evaluation for RC Sewer Structure Repaired with Bacteria Mixed Coating: Through Probabilistic and Deterministic Method |
title_fullStr | Service Life Evaluation for RC Sewer Structure Repaired with Bacteria Mixed Coating: Through Probabilistic and Deterministic Method |
title_full_unstemmed | Service Life Evaluation for RC Sewer Structure Repaired with Bacteria Mixed Coating: Through Probabilistic and Deterministic Method |
title_short | Service Life Evaluation for RC Sewer Structure Repaired with Bacteria Mixed Coating: Through Probabilistic and Deterministic Method |
title_sort | service life evaluation for rc sewer structure repaired with bacteria mixed coating through probabilistic and deterministic method |
topic | <i>Rhodobacter capsulatus</i> sewage concrete surface coating sulfate ion service life cover depth |
url | https://www.mdpi.com/1996-1944/14/18/5424 |
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