低放射性廢棄物處置場設施之工程障壁材料由混凝土所組成，不同於一般結構物，服務年限需長達百年以上，因此對障壁混凝土材料可能產生之劣化及耐久性影響必須加以評估。
本研究主要針對工程障壁材料以實驗室模擬可能遭受之劣化狀況，製作符合ACI 349-97核能安全混凝土結構物材料規定配比及完整性容器可能採用之配比等試體，進行氯離子入侵、硫酸鹽侵蝕、溶出失鈣效應等劣化試驗，瞭解並分析其劣化之情況。氯離子入侵及硫酸鹽侵蝕試驗結果顯示，低水膠比以及添加較多卜作嵐礦物摻料之混凝土內部結構較緻密，導致離子擴散係數較小，但離子會在混凝土表層持續累積，造成表層離子濃度較高。溶出失鈣效應試驗以浸泡硝酸銨溶液之加速試驗來判斷配比的優劣，浸泡純水及人工海水進行溶出失鈣效果可不考慮其劣化影響。
為推估氯離子引致之腐蝕劣化，依氯離子入侵濃度預估鋼筋開始腐蝕之時間，主要影響因素為擴散係數與時間因子。本文針對不同歷時時間濃度剖面進行殘差分析，利用信賴度之概念建立其擴散係數與時間m因子之分佈，在氯離子引致腐蝕濃度門檻值與保護層厚度條件下，推估鋼筋開始腐蝕之時間，以建立障壁混凝土服務年限之推估模式。
劣化試驗結果顯示，完整性容器可能採用之配比在抵抗各種侵蝕能力都優於ACI 349-97配比，主要因為完整性容器配比低水膠比，內部結構較緻密，致使有害離子在表面累積而無法進入混凝土內部。而在溶出失鈣方面也比ACI 349-97配比有較佳之抗溶出失鈣之能力。

Engineering barrier for the final disposal of low-level radioactive wastes serves to isolate the wastes from human biosphere for a very long design life. Concrete has been widely accepted as engineering barrier material due to its longevity, which provides good structural integrity for prolonged service life. The half life of 137Cs and 90Sr, the 2 major radio nuclides in low-level wastes, is about 30 years. It is estimated that the radioactivity of these nuclides would decay to a level that is comparable to the background in 10 half-life cycles. Hence, concrete material is expected to serve at least 300 years in the final disposal site. However, the adverse environmental conditions at the disposal site could attack concrete barrier material and results in degradation of the material.
This study focuses on the effect of the chloride ingress, sulfate attack and leaching on the degradation rate of the long-term durability of the concrete. Test and analysis on concrete mixtures include: (1) high integrity container of H mixture, and (2) ACI 349-94 mixture designs.
The results show that concrete internal structures with a low water-binder ratio are more compact, resulting in a lower ion diffusion coefficient. In terms of the diffusion coefficient, H mixture is better than ACI 349-94 mixture. To estimate the time to initial corrosion caused by chloride, two main factors are taken into consideration: the diffusion coefficient and the time factor. Concentration profiles of chloride at different times are used for residual analysis. To define the acceptable range of the diffusion coefficient, we looked into the threshold of chloride concentration causing corrosion and the cover thickness of concrete, and further estimate the time to initial corrosion of steel in concrete.
The study attained the following findings and conclusions:
(1) The diffusion coefficient of chloride and sulfate into concrete decreases as the age and exposure period increases. The use of pozzolanic materials in concrete mixes reduces the diffusion coefficient by providing a fine internal pore structure, which, in turn, improves the resistance of concrete to chloride ingress and sulfate attack.
(2) The leaching degradation in concentrated ammonium nitrate solution is faster than that obtained with water as medium and is useful for accelerating leaching degradation. Leaching of concrete in pure water and synthetic sea water is very limited, and is not considered to cause significant porosity increase and promote the chloride ingress and sulfate attack much.
(3) A reliability-based scheme for estimating the service life of concrete barrier has been developed based on a large amount of chloride ingress profiles obtained from various concrete specimens with different water/binder ratios and pozzolanic admixtures subjected to exposure of chloride ions for as long as 3 years. The predicted service life is found to be sensitive to not only the diffusion coefficient of concrete, but also the time factor on the reduction of diffusion coefficient, which requires long-term testing of concrete for determination.

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，http://www.aec.gov.tw/。
行政院環境保護署 全國環境水質監測資訊網，http://wqshow.epa.gov.tw/。
王櫻茂，「混凝土結構物的耐久性系列-鹼骨材反應（Ⅰ）中性化（Ⅱ）」 ,國立成功大學土木結構材料試驗室，台南 (2000)。
王櫻茂、吳振成、楊宏儀、田永銘、陳裕新，「台灣地區鹼-骨材反應特性之研究」，行政院國科會專題研究報告，NSC78-0410-E006-20（1989）。
王韡蒨，「台灣地區活性粒料之檢測方法研究」，碩士論文，國立中央大學土木工程研究所，中壢(2003)。
李明君，李釗，「使用飛灰等摻料製作高強度混凝土之探討」，應用礦物摻料提昇混凝土品質，台灣營建研究院 (1999)。
黃兆龍，「混凝土性質及行為」，詹氏書局 (1999)。
黃兆龍，「高性能混凝土理論與實務」，詹氏書局 (2003)。
陳柏忠，「用過核子燃料乾式貯存設施之混凝土材料耐久性研究」，碩士論文，國立中央大學土木工程研究所，中壢(2005)。
鄒蕙如，「最終處置場黏土障壁材料之傳輸行為研究」，碩士論文，國立中央大學土木工程研究所，中壢(2005)。
盧秉瑋，「混凝土工程障壁之氯離子及失鈣劣化行為」，碩士論文，國立中央大學土木工程研究所，中壢 (2006)。
吳清哲，「低放射性廢棄物處置場障壁受硫酸鹽侵蝕之劣化模式評估」，碩士論文，國立中央大學土木工程研究所，中壢(2006)。
潘奕銘，「低放射性廢棄物處置場混凝土障壁材料溶出劣化效應評估」，碩士論文，國立中央大學土木工程研究所，中壢(2007)。
邱怡瑄，「低放處置場工程障壁之溶出失鈣及劣化敏感度分析」，碩士論文，國立中央大學土木工程研究所，中壢(2009)。
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）。
邱耀輝，「硫酸鹽侵蝕對低放處置場障壁混凝土之劣化及推估研究」，碩士論文，國立中央大學土木工程研究所，中壢（2011）。
4SIGHT (URL)：http://ciks.cbt.nist.gov/4sight/
DataFit (URL)：http://www.curvefitting.com/.
Life-365 (URL)：http://www.life-365.org/.
Aguilera, J., Martínez-Ramírez, S., Pajares-Colomo, I., Blanco-Varela, M. T., (2003), “Formation of thaumasite in carbonated mortars.” Cement and Concrete Composites, Vol. 25, pp. 991-996.
Ahmad, S. (2003), “Reinforcement corrosion in concrete structures, its monitoring and service life prediction–a review,”, Cement and Concrete Composites, Vol. 25, pp. 459-471.
Aköz, F., Türker, F., Koral, S., and Yüzer, N. (1999), “Effects of raised temperature of sulfate solutions on the sulfate resistance of mortars with and without silica fume.” Cement and Concrete Research, Vol. 29, pp. 537-544
Atkinson, A., D. j. Goult, and J. A. Hearne. (1984), “An Assessment of the Long-Term Durability of Concrete in Radioactive Waste Repositories” , AERE-R11465, Harwell, U.K.
Atkinson, A. and J. A. Hearne. (1990), “Mechanistic Model for the Durability of concrete Barriers Exposed to Sulphate-Bearing Groundwaters,” Materials Research Society, 176, p.149-156.
A1-Dulaijan, S. U., Maslehuddin, M., A1-Zahrani, M. M., Sharif, A. M., Shameem, M., and Ibrahim, M. (2003), “Sulfate resistance of plain and blended cements exposed varving concentrations of sodium sulfate.” Cement and Concrete Composites, Vol. 25, pp. 429-437.
Al-Amoudi, O. B. (2002), “Attack on plain and blended cements exposed to aggressive sulfate environments.” Cement and Concrete Composites, Vol. 24, pp. 305-316.
Bai, J., Wild, S., and Sabir, B. B. (2003), ”Chloride ingress and strength loss in concrete with different PC-PFA-MK binder compositions exposed to synthetic seawater,” Cement and Concrete Research, Vol. 33, pp.353-362.
Balouch, S. U., Forth, J. P., Granju, J. L. (2010), “Surface corrosion of steel fibre reinforced concrete,” , Cement and Concrete Research, Vol. 40, pp. 410-414.
Bazant, Z. P. (1979a), “Physical Model for Steel Corrosion in Concrete Sea Structures Theory,” Journal of Structural Division , Vol. 105 , No. ST6 , ASCE , pp. 1137-1153.
Bazant, Z. P. (1979b), “Physical Model for Steel Corrosion in Concrete Sea Structures Theory,” Journal of Structural Division , Vol. 105 , No. ST6 , ASCE , pp. 1155-1166.
Boddy Andrea, Bentz Evan, Thomas, M. D. A., and, Hooton, R. D. (1999), “An overview and sensitivity study of a multimechanistic chloride transport model,” Cement and Concrete Research, Vol. 29, pp. 827-837.
Boyda, A. J., Mindess, S. (2003), “The use of tension testing to investigate the effect of W/C ratio and cement type on the resistance of concrete to sulfate attack.” Cement and Concrete Research, Vol. 34, pp. 373-377.
Brandt, A. M. (1995), Cement-based Composites: Material, Mechanical Properties and Performance., E & FN SPON, U. K..
Brown, P., Hooton, R. D. (2002), “Ettringite and thaumasite formation in laboratory concretes prepared using sulfate-resisting cements,” Cement and Concrete Composites, Vol. 24, pp. 361-370.
Brown, P. W. (2002), “Thaumasite formation and other forms of sulfate attack.” Cement and Concrete Composites, Vol. 24, pp.301-303.
Cao, H. T., Bucea, L., Ray, A., Yozghatlian, S. (1997), “The effect of cement combosition and PH of environm ent on sulfate resistance of Portland cements and blended cements.” Cement and Concrete Composites, Vol. 19, pp. 161-171.
Chatterji, S. (1995), “On the applicability of Fick's second law to chloride ion migration through Portland cement concrete.” Cement and Concrete Research, Vol. 25, No. 2, pp. 299-303.
Diamond, S. (1996), “Delayed ettringite formation - processes and problems,” Cement and Concrete Composites, Vol. 18, No. 3, pp. 205-215.
Drimalas, T., Clement, J. C., and Folliard, K. J. (2010), “Laboratory and Field Evaluations of External Sulfate Attack in Concrete,” The University of Texas at Austin.
Ferraris, C.F., J.R. Clifton, P.E. Stutzman and E.J. Garboczi. (1997), “Mechanisms of degration of Portland cement-based systems by sulfate attack.” Mechanisms of chemical degradation of cement-based systems. Ed. K.L. Scrivener and J.F.Young. London ; New York : E & FN Spon,. 185-192
Gang Lin, Yinghua Liu, Zhihai Xiang (2010), “Numerical modeling for predicting service life of reinforced concrete structures exposed to chloride environments,’’ , Cement and Concrete Composites, Vol. 32, pp. 571–579.
Granju, J. L. and Balouch, S. U. (2005), “Corrosion of steel fibre reinforced concrete from the cracks,” , Cement and Concrete Research, Vol. 35, pp. 572-577.
Haj-Ali, R. M., Kurtis, K. G. and Sthapit, A. R. (2001), “Neural Network Modeling of Concrete Expansion during Long-Term Sulfate Exposure,” , ACI Materials Journal, Vol. 98, pp.36-43.
Hanadi, S. R., Philip, B. B., and Charles, J. N. (1999), Ground Water Contamination : Trasport and Remediation, Prentice-Hall, Inc., Upper Saddle River, New Jersey, U.S.A.
Hartshorn, S. A., Sharp, J. H., and Swamy, R. N. (2002), “The thaumasite form of sulfate attack in Portland-limestone cement mortars stored in magnesium sulfate solution.” Cement and Concrete Composites, Vol. 24, pp. 351-359.
Higgins, D. D., Crammond, N. J. (2003), “Resistance of concrete containing ggbs to the thaumasite form of sulfate attack.” Cement and Concrete Composites, Vol. 25, pp. 921-929.
Hoglund, L. O. (1992), “Some notes on ettringite formation in cementitious materials - influence of hydration and thermodynamic constraints for durability.” Cement and Concrete Research, Vol. 22, No. 2-3, pp. 217-228.
Irassar, E. F., Maio, A. D., and Batic, O. R. (1996), “Sulfate attack on concrete with mineral admixtures.” Cement and Concrete Research, Vol. 26, No. 1, pp. 113-123.
Irassar, E. F., Bonavetti, V.L., Gonzalez, M. (2003), “Microstructural study of sulfate attack on ordinary and limestone Portland cements at ambient temperature.” Cement and Concrete Research, Vol. 33, pp. 31-41.
Jieting Zhang, Zoubir Lounis (2009), “Nonlinear relationships between parameters of simplified diffusion-based model for service life design of concrete structures exposed to chlorides,” , Cement and Concrete Composites, Vol. 31, pp. 591–600.
Kamali, S., Gerard, B. and Moranville, M. (2003),“Modelling the leaching kinetics of cement-based materials－influence of materials and environment, ” Cement and Concrete Composities, Vol. 25, pp. 451-458.
Kouloumbi, N. G., Batis, and Pantazopoulou, P. (1995), “Efficiency of Natural Greek Pozzolan in Chloride Induced Corrosion of Steel Reinforcement,”, Cement, Concrete Aggregates, Vol. 17, No. 1, pp. 18-25.
Kurtis, K. E., Monteiro, P. J., and Madanat, S. (2000), “Empirical Models to Concrete Expansion Caused by Sulfate Attack. ” ACI Materials Journal, Vol. 97, No. 2, Mar.- Apr. pp. 156-161.
Lagerblad B., J.Marchand and J.P. Skalny. (1999), “Long term test of concrete resistance against sulphate attack.” Materials Science of concrete : Sulfate attack Mechanisms,. American Ceramic Society, Westerbrook, Ohio: 325-336 ,
Lagerblad, B. (2001), “Leaching performance of concrete base on studies of samples from old concrete constructions, ” Swedish Cement and Concrete Research Institute.
Lee, S. T., Moon, H. Y., and Swamy, R. N. (2005), “Sulfate attack and role of silica fume in resisting strength loss.” Cement and Concrete Composites, Vol. 27, pp. 65-76.
Liu, Y. and Weyers, R. E. (1998), “Modeling the Time-to-Corrosion Cracking in Chloride Contaminated Reinforced Concrete Structures,” ACI Materials Journal, Vol. 95, No.6, pp. 675-681.
Leng, F., Feng, N., and Lu, X. (2000), “An experimental study on the properties of resistance to diffusion of chloride ions of fly ash and blast furnace salg concrete,” Cement and Concrete Research, Vol. 30, pp. 989-992.
Mbessa, M., Pe´ra, J. (2001), “Durability of high-strength concrete in ammonium sulfate solution.” Cement and Concrete Research, Vol. 31, pp. 1227-1231.
Mehta, P. K. (1986), Concrete Structure Properties and Materials., Prentice Hall, Inc., Englewood Cliffs, New Jersey, U.S.A..
Monteiroa, P. J. M., Kurtis, K. E. (2003), “Time to failure for concrete exposed to severe sulfate attack.” Cement and Concrete Research, Vol. 33, pp. 1159-1163.
Mulenga, D. M., Stark, J., and Nobst, P. (2003), “Thaumasite formation in concrete and mortars containing fly ash.” Cement and Concrete Composites, Vol. 25, No. 8, pp. 907-912.
Nilsson, L., Poulsen, E., Sandberg, P. H., Sorensen, E., and Klinghoffer, O. (1996), “Chloride penetration into concrete, state-of-the-art, transport processes, corrosion initiation, test methods and prediction models,” The Road Directorate, Copenhagen.
Park, Y. S., Suh, J. K., Lee, J. H., and Shin, Y. S. (1999), “Strength deterioration of high strength concrete in sulfate environment.” Cement and Concrete Research, Vol. 29, pp. 1397-1402.
Reddy, B., Glass, G. K., Lim, P. J., Buenfeld, N. R., (2002), “On the corrosion risk presented by chloride bound in concrete,” , Cement and Concrete Composites, Vol. 24, pp. 1-5.
Romer, M. (2003), “Steam locomotive soot and the formation of thaumasite in shotcrete,” Cement and Concrete Composites, Vol. 25, pp. 1173-1176.
Sahu, S., Badger, S., Thaulow, N., (2003), “Mechanism of thaumasite formation in concrete slabs on grade in Southern California.” Cement and Concrete Composites, Vol. 25, pp. 889-897.
Saito, H. and Nakane, S. (1999), “Comparison between diffusion test and electrochemical acceleration test for leaching degradation of cement hydration products, ” ACI Mater J 96 (2) 208-211.
Saito, H. and Deguchi, A. (2000), “Leaching tests on different mortars using accelerated electrochemical method, ” Cement and Concrete Research , Vol. 30, pp. 1815-1825.
Santhanama, M., Cohenb, M. D., Olekb, J. (2003), “Effects of gypsum formation on the performance of cement mortars during external sulfate attack.” Cement and Concrete Research, Vol. 33, pp. 325-332.
Santhanam, M., Cohen, M. D., and Olek, J. (2002), “Modeling the effects of solution temperature and concentration during sulfate attack on cement mortars.” Cement and Concrete Research, Vol. 32, pp. 585-592.
Santhanam, M., Cohen, M. D., and Olek, J. (2002), “Mechanism of sulfate attack: A fresh look Part 1: Summary of experimental results. Proposed mechanisms.” Cement and Concrete Composites, Vol. 32, pp. 915-921.
Santhanam, M., Cohen, M. D., and Olek, J. (2002), “Mechanism of sulfate attack: a fresh look Part 2. Proposed mechanisms.” Cement and Concrete Composites, Vol. 33, pp. 341-346.
Sarkar, S., Mahadevan, S., Meeussen, J.C.L., van der Sloot, H., Koaaon, D. S. (2010), “Numerical simulation of cementitious materials degradation under external sulfate attack.” Cement and Concrete Composites, Vol. 32, pp. 241-252.
Seatta, A. V., Scotta, R. V., and Vitaliani, R. V. (1993), “Analysis of Chloride Diffusion Into Partially Saturated Concrete,” ACI Material, Vol. 90, No. 5, pp. 441-451.
Seng, C. K. and Hong, Z. M. (2002), “Water permeability and chloride penetrability of high-strength lightweight aggregate concrete,” Cement and Concrete Research, Vol. 32, pp. 639-645.
Smallwood, I., Wild, S., and Morgan, E. (2003), “The resistance of metakaolin (MK)-Portland cement (PC) concrete to the thaumasite-type of sulfate attack (TSA)-Programme of research and preliminary results.” Cement and Concrete Composites, Vol. 25, pp. 931-938.
Snyder, K.A. (2001), “The relationship between the formation factor and the diffusion coefficient of porous materials saturated with concentrated electrolytes: theoretical and experimental considerations, ” Concrete Science and Engineering, Vol. 3, No. 12, pp. 216-224.
Snyder, K.A. (2001), “Validation and Modification of the 4SIGHT Computer Program, ” National Institute of Standards and Technology Gaithersburg, MD 20899, NISTIR 6747
Suryavanshi, A. K., Scantlebury, J. D. and Lyon, S. B. (1996), “Mechanism of Friedel’s salt formation in cement rich in tri-calcium aluminate,” Cement and Concrete Research, Vol. 26, pp. 717-727.
Sherman, R. M., David, M. B., and Pfeifer, D. W. (1996), “Durability aspects of precast prestressed Concrete-Part 1 and 2,” Journal of PCI, Vol. 41, No. 4, pp. 60-64.
Shuman, R., Rogers, V. C. and Shaw, R. A. (1989), “The Barrier Code for Predicting Long-Term Concrete Performance.” Waste Management 89, University of Arizona.
Sims, I., Huntley, S. A. (2004), “The thaumasite form of sulfate attack-breaking the rules.” Cement and Concrete Composites, Vol. 26, pp. 837-844.
Stanish, K. D., Hooton, R. D., and Thomas, M. D. A. (2000), “Testing the chloride penetration resistance of concrete：a literature review.” Federal Highway Administration.
Thomas, M. D. A., Shehata, M. H., Shashiprakash, S. G., Hopkins, D. S., and Cail, K. (1999), “Use of ternary cementitious systems containing silica funme and fly ash in concrete,’’ , Cement and Concrete Research, Vol. 29, pp. 1207-1214.
Torres, S. M., Sharp, J. H., Swamy, R. N., Lynsdale, C. J., and Huntley, S. A. (2003), “Long term durability of Portland-limestone cement mortars exposed to magnesium sulfate attack,” Cement and Concrete Composites, Vol. 25, pp. 947-954.
Torii, K., Taniguchi, K., and Kawamura, M. (1995), “Sulfate resistance of high ash content concrete.” Cement and Concrete Research, Vol. 25 , pp. 759-768.
Tian, B., Cohen, M. D. (2000), “Does gypsum formation during sulfate attack on concrete lead to expansion ?.” Cement and Concrete Research, Vol. 30, pp. 117-123.
Tixier, R. (2000), ‘‘Microstructural development and sulfate attack modeling in blended cement-based materials.’’ PhD dissertation, Arizona State University, Tempe, Ariz.
Tixier, R., Mobasher, B. (2003), “Modeling of Damage in Cement-Based Materials Subjected to External Sulfate Attack. I: Formulation.” ASCE Journal of Materials Engineering, Vol. 15, No. 4, pp. 305-313.
Tixier, R., Mobasher, B. (2003), “Modeling of Damage in Cement-Based Materials Subjected to External Sulfate Attack. II: Comparison with Experiments.” ASCE Journal of Materials Engineering, Vol. 15, No. 4, pp. 314-322.
Tumidajski, P. J., Chan, G. W., and Philipose, K. E. (1995), “An effective diffusivity for sulfate transport into concrete.” Cement and Concrete Research, Vol. 25, No. 6, pp. 1159-1163.
Trägårdh, J. and Lagerblad, B. (1998).“Leaching of 90-year old concrete mortar in contact with stagnant water.” Swedish Cement and Concrete Research Institute.
Tritthart, J. and Cavlek, K. (2000), “Determination of total and free chloride in cement paste and concrete,” RILEM Proceedings, Pro 19, pp.429-437.
Tsivilis, S., Kakali, G., Skaropoulou, A., Sharp, J. H., and Swamy, R. N. (2003), “Use of mineral admixtures to prevent thaumasite formation in limestone cement mortar.” Cement and Concrete Composites, Vol. 25, pp. 969-976.
Uhlig, H. H., and Revie, R. W. (1991), Corrosion and Corrosion Control, Third Edition, pp. 90-122.
Young, J. F., Mindess, S. and Daewin, D. (2002), Concrete, Prentice-Hall, Inc., Upper Saddle River, New Jersey, U.S