| 研究生: |
陳品臻 PIN-ZHEN CHEN |
|---|---|
| 論文名稱: |
低放處置場混凝土障壁受氯離子入侵之使用年限推估 |
| 指導教授: |
黃偉慶
Wei-Hsing Huang |
| 口試委員: | |
| 學位類別: |
碩士 Master |
| 系所名稱: |
工學院 - 土木工程學系 Department of Civil Engineering |
| 論文出版年: | 2015 |
| 畢業學年度: | 103 |
| 語文別: | 中文 |
| 論文頁數: | 121 |
| 中文關鍵詞: | 氯離子 、擴散係數 、使用年限 |
| 外文關鍵詞: | chloride ions, diffusion coefficient, service life |
| 相關次數: | 點閱:19 下載:0 |
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低放射性廢棄物最終處置將使用混凝土障壁,因營運時間長,故須針對可能遭遇不良環境探討其使用年限,本研究針對兩種障壁混凝土受到氯離子入侵可能情形進行服務年限的推算。
本研究針對可能用於製作盛裝容器(含蓋子) 配比C、封蓋之填縫材料配比M,依據ASTM C1556規範製作標準試體,於養治齡期28天、90天、183天時,將試體浸泡氯化鈉溶液36天,再以ASTM C1152量測不同齡期之混凝土濃度剖面,藉由費克第二定律衍生式,計算出表面氯離子濃度與瞬時擴散係數。並以實驗數據計算瞬時擴散係數隨時間增加而降低之速率,求取時間因子m 值,據以推算不同齡期瞬時擴散係數的變化。
研究團隊先前完成之配比HIC-C與配比HIC-M依據AASHTO T259規範製作之試體,浸泡於3%氯化鈉水溶液中,再依據AASHTO T260量測不同齡期之混凝土濃度剖面,藉由費克第二定律衍生式,計算表面氯離子濃度與擴散係數。混凝土表面氯離子濃度隨浸泡時間增加而增加,依據表面氯離子濃度與時間的自然對數關係,求出關係式推算不同歷時表面氯離子濃度,已完成四年之數據,並將結果與ASTM法所得加以比較。
依據ACI所發表程式Life-365,針對鋼筋混凝土受氯離子入侵之服務年限推估方法,發展一套計算程序,可用於推估未來處置設施其使用年限,並藉由此計算程序推估配比HIC-C與配比HIC-M濃度剖面,與四年氯離子濃度實驗數據比較,其結果相近,故此計算程序具有一定可信度,而藉由此計算程序推估盛裝容器桶壁35mm處氯離子濃度到達0.05%之時間為使用年限,所得使用年限皆超過500年。
The final disposal of low-level radioactive wastes will be using concrete barriers. Due to the long service time, it is likely to encounter adverse environments and thus the service life of the concrete barrier needs be explored.
In this study, two concrete mixes possibly used for fabricating highly integrated containers, namely mixes C and M, were tested by ASTM C1556 standard procedures to determine their diffusion coefficient under the attack of chloride irons. The profile of chloride concentration at various depths was determined for concrete specimens at 28, 90, and 183 days of age after immersing in NaCl solution for 36 days. Then, Fick’s second law was used to obtain chloride diffusion coefficient and surface chloride content using non-linear regression technique. And the experimental data were used to estimate the change in diffusion coefficient with time for the two concrete mixes.
Also, based on AASHTO T259 test method, concrete specimens immersed in NaCl solution for about 4 years were determined for their apparent diffusion coefficient. And the results obtained from the two methods were compared in the study.
Finally, a computation scheme was developed to calculate the time required for chloride irons to penetrate 35 mm (approximately one-half of the thickness of containers) of the concrete barrier and reaching a concentration level of 0.05% by weight of concrete. The calculated results were compared and verified with those derived from Program Life-365, and found to be very similar. By using the computation scheme, the service life, in terms of resistance to chloride attack, of the two concrete mixes are both found to be more than 500 years.
行政院原子能委員會:http://www.aec.gov.tw/。
台灣電力公司:http://www.taipower.com.tw/。
王茂齡(1987),輸送現象,高立圖書有限公司。
行政院原子能委員會,低放射性廢棄物(低階核廢料)最終處置的安全管理(2014)。
陳仕豪,「氯離子入侵混凝土之擴散係數時間效應與飛灰之影響」,碩士論文,國立中央大學土木工程研究所,中壢(2010)。
羅欣蕙,「低放射性廢棄物障壁混凝土受氯離子入侵之劣化及預估研究」,碩士論文,國立中央大學土木工程研究所,中壢(2011)。
陳昱安,「低放處置場工程障壁受氯離子侵蝕服務年限預估研究」,碩士論文,國立中央大學土木工程研究所,中壢(2012)。
牟妍樺,「低放處置場混凝土工程障壁受氯離子侵襲之服務年限信賴度研究」,碩士論文,國立中央大學土木工程研究所,中壢(2013)。
彭琦茵,「障壁混凝土受氯離子入侵剖面及使用年限推估之方法比較」,碩士論文,國立中央大學土木工程研究所,中壢(2015)。
DataFit (URL):http://www.curvefitting.com/.
Life-365 (URL):http://www.life-365.org/.
Ann, K. Y., Ahn, J. H., and Ryou, J. S., “The importance of chloride content at the concrete surface in assessing the time to corrosion of steel in concrete structures,”Construction and Building Materials,Vol.23,pp.239- 245(2009).
ASTM C1556-11 Standard Test Method for Determining the Apparent Chloride Diffusion Coefficient of Cementitious Mixtures by Bulk Diffusion.
ASTM C1152-12 Standard Test Method for Acid-Soluble Chloride in Mortar and Concrete1.
ASTM C642-13 Standard Test Method for Density, Absorption, and Voids in Hardened Concrete.
AASHTO T259-02 Standard Method of Test for Resistance of Concrete to Chloride Ion Penetration.
AASHTO T260-97 Standard Method of Test for Sampling and Testing for Chloride Ion in Concrete and Concrete Raw Materials.
Chalee, W., Jaturapitakkul, C., and Chindaprasirt, P., “Predicting the chloride penetration of fly ash concrete in seawater,” Marine Structures, Vol. 22, No.1, pp. 341-353(2009).
“Life_-365 Service Life Prediction Model and Computer Program for Predicting the Service Life and Life-Cycle Costs of Reinforced Concrete Exposed to Chlorides” (2013).
Korpa, A., Trettin, R.,“The influence of different drying methods on cement paste microstructures as reflected by gas adsorption: Comparison between freeze-drying (F-drying),D-drying, P-drying and oven-drying methods” Cement and Concrete Research, Vol. 36, pp. 634-649(2006).
Mangat, P. S., and Molloy, B. T., “Prediction of long term chloride concentration in concrete,” Material and Structures, Vol. 27, pp. 338-346(1994).
Nokken, M., Boddy, A., Hooton, R. D., and Thomas, M. D. A., “Time dependent diffusion in concrete−three laboratory studies,” Cement and Concrete Research, Vol. 36, No. 1, pp. 200-207(2006).
Metha,P.K., Monterio, P.J.M., Concrete, Microstructure, Properties and Materials,McGraw-Hill, London,( 2006).
Sherman, R. M., David, M. B., and Pfeifer, D. W., “Durability aspects of precast prestressed Concrete-Part 1 and 2,” Journal of PCI, Vol. 41, No. 4, pp. 60-64(1996).
Song, H.-W., Lee, C.-H., and Ann, K. Y., “Factors influencing chloride transport in concrete structures exposed to marine environments,” Cement and Concrete Composites, Vol. 30, pp. 113-121(2008).
Stanish, K., and Thomas, M., “The use of bulk diffusion tests to establish time-dependent concrete chloride difftsion coefficients,” Cement and Concrete Research, Vol. 33, pp. 55-62(2003).
Young, J. F., Mindess, S., and Darwin, D. (2002), Concrete, Prentice Hall, Inc., Upper Saddle River, New Jersey, U.S.A..
Zibara, H. R., Pérezfki, B., Hooton, D. M., and Thomas, M. D. A. (2000), ”A study of the effect of chloride binding on service life predictions,” Cement and Concrete Research, Vol. 30, pp. 1215-1223.