PSI - Issue 33

Available online at www.sciencedirect.com Structural Integrity Procedia 00 (2019) 000–000 Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2019) 000–000 ScienceDirect

www.elsevier.com/locate/procedia

www.elsevier.com/locate/procedia

ScienceDirect

Procedia Structural Integrity 33 (2021) 630–645

IGF26 - 26th International Conference on Fracture and Structural Integrity Experimental tests on vapor and gas permeability of concrete boxes Fabrizio Pittau a , Fabiuo Doveri a , Mario Lucio Puppio a,  , Flavio Stochino a , IGF26 - 26th International Conference on Fracture and Structural Integrity Experimental tests on vapor and gas permeability of concrete boxes Fabrizio Pittau a , Fabiuo Doveri a , Mario Lucio Puppio a,  , Flavio Stochino a ,

Fausto Mistretta a and Mauro Sassu a . a University of Cagliari, viale Marengo 1, Cagliari 09123, Italy. Fausto Mistretta a and Mauro Sassu a . a University of Cagliari, viale Marengo 1, Cagliari 09123, Italy.

© 2021 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of the scientific committee of the IGF ExCo © 2021 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review Statement: Peer-review under responsibility of the scientific committee of the IGF ExCo Keywords: experimental tests; reinforced concrete aging; vapor tightness; gas tightness; thermal analysis, concrete tigthness, concrete permeability. Abstract The use of reinforced concrete (r.c.) in industrial plants presents new challenge in the design of gas containments. The r.c. has advantages in terms of costs, shape optimization and monolithicity, although its permeability to gas and vapor is a critical issue. The concrete has well-known performances for water containment (as dams or reservoir) but not for the vapor tightness, due to the natural porosity and physiological cracking due to shrinkage and low traction strength. Special additives can mitigate the problem of the natural cracking that is physiologic for non-prestressed concrete; nevertheless, coatings can solve this problem. The internal coating can produce proper insulation from vapor and gas, but it is difficult to survey and to repair. The external coating is characterized by opposite advantages. In this paper the effectiveness of four different type of the external coatings on the vapor tightness of concrete boxes is analyzed. The experimental test is developed considering small-scale boxes (a cube of 1,20 m side) with a thickness of about 10 cm. Four speci ens of cubic concrete boxes made in vibro-compressed concrete are coated with four different layers. The tightness test is carried out by the application of an internal pressure given by blown nitrogen. The tests highlight the level of tightness of each treatment and highlights strength and drawbacks of each coating. © 2021 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review Statement: Peer-review under responsibility of the scientific committee of the IGF ExCo Keywords: experimental tests; reinforced concrete aging; vapor tightness; gas tightness; thermal analysis, concrete tigthness, concrete permeability. Abstract The use of reinforced concrete (r.c.) in industrial plants presents new challenge in the design of gas containments. The r.c. has advantages in terms of costs, shape optimization and monolithicity, although its permeability to gas and vapor is a critical issue. The concrete has well-known performances for water containment (as dams or reservoir) but not for the vapor tightness, due to the natural porosity and physiological cracking due to shrinkage and low traction strength. Special additives can mitigate the problem of the natural cracking that is physiologic for non-prestressed concrete; nevertheless, coatings can solve this problem. The internal coating can produce proper insulation from vapor and gas, but it is difficult to survey and to repair. The external coating is characterized by opposite advantages. In this paper the effectiveness of four different type of the external coatings on the vapor tightness of concrete boxes is analyzed. The experimental test is developed considering small-scale boxes (a cube of 1,20 m side) with a thickness of about 10 cm. Four specimens of cubic concrete boxes made in vibro-compressed concrete are coated with four different layers. The tightness test is carried out by the application of an internal pressure given by blown nitrogen. The tests highlight the level of tightness of each treatment and highlights strength and drawbacks of each coating.

 Corresponding author. E-mail address: mariol.puppio@unica.it  Corresponding author. E-mail address: mariol.puppio@unica.it

2452-3216 © 2021 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review Statement: Peer-review under responsibility of the scientific committee of the IGF ExCo 2452-3216 © 2021 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review Statement: Peer-review under responsibility of the scientific committee of the IGF ExCo

2452-3216 © 2021 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of the scientific committee of the IGF ExCo 10.1016/j.prostr.2021.10.070