The Experts below are selected from a list of 57 Experts worldwide ranked by ideXlab platform
Tsunehisa Handa - One of the best experts on this subject based on the ideXlab platform.
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Effect of Structural Discontinuities of Welded Joints on Brittle Crack Propagation Behavior : Brittle Crack Arrest Design for Large Container Ships-3 :
ClassNK technical bulletin, 2020Co-Authors: Tsunehisa Handa, Toshiyuki Matsumoto, Hiroshi Yajima, Shuji Aihara, Hitoshi Yoshinari, Kazuhiro Hirota, Masanobu Toyoda, Takaaki Kiyosue, Takehiro Inoue, Tomoya KawabataAbstract:Brittle fracture of hull structure causes serious structural, fatal and environmental damage once it happens. Therefore, ships are basically designed and constructed so that a brittle crack does not occur. Further, if by chance a brittle crack occurs, it is essentially and extremely important that a backup brittle crack arresting function is provided to arrest its propagation and to ensure structural reliability. Either fillet welding or partial penetration welding is applied in cruciform joints comprising the Strength Deck and hatch side coaming, in which extremely thick steel plates are used. In this research, model experiments were conducted supposing that a brittle crack that has undergone linear propagation in a weld in the hatch coaming extends into a cruciform joint of the hatch side coaming and Strength Deck, and the effect of structural discontinuities on brittle crack propagation behavior in the cruciform joint was investigated assuming the case in which the lower edge of the butt welding of the hatch side coaming is melted to the Deck plate. This research was conducted by a research committee of Nippon Kaiji Kyokai (ClassNK), and the results were summarized and incorporated in their “Guidelines on Brittle Crack Arrest Design.”(Nippon Kaiji Kyokai, 2009)
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Brittle Crack Propagation/Arrest Behavior in Full Penetration T-joint
Journal of the Japan Society of Naval Architects and Ocean Engineers, 2020Co-Authors: Tsunehisa Handa, Kimihiro Nishimura, Testuya Tagawa, Kenji Oi, Fumiyoshi MinamiAbstract:Arrestability of brittle cracks is extremely important in the structural integrity of welded joints of heavy gauge steel plates used in large container ships. Recently, a great attention has been focused on potential crack propagation along welds made with large heat input. In this study, a T-joint is applied to the Strength Deck structure of container ships to enhance crack arrestability. Material crack arrest toughnesses, Kca, of some steel plates are varied. The ESSO tests of T-joint components showed that a brittle crack is arrested at the T-joint if the steel plate used in the flange has a high Kca value in the range from 4900 to 7300 N/mm ³/². Finite element (FE)-analyses of the stress intensity factor K indicated that brittle crack propagation is arrested under the condition that the K-value at the running crack tip is less than the Kca of the material. It is noted in the T-joint that the K-value at the deepest point of the crack decreases and is finally below the Kca of the flange plate when a brittle crack rapidly penetrates the flange plate to a depth of 30-40mm. These phenomena show the advantage of the T-joint in brittle crack arrestability in the flange plate of the Strength Deck structure.
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Brittle crack propagation/arrest behavior in T-joint structure of heavy gauge steel plate
Welding in the World, 2015Co-Authors: Tsunehisa Handa, Kenji Oi, Tetsuya Tagawa, Fumiyoshi MinamiAbstract:Brittle crack arrestability is extremely important in welded joints of heavy gauge steel plates used in large container ships. Recently, much attention has been focused on potential crack propagation along welds fabricated by large heat input welding. This paper examines the application of a T-joint to the Strength Deck structure of container ships to enhance crack arrestability. The unwelded face and the crack arrest toughness, K _ca, for crack arrest were varied. In the case of a T-joint with an unwelded face, the ESSO test of the T-joint components showed that a brittle crack arrested at the T-joint embedding the unwelded face. In the case of a full penetration T-joint, the brittle crack was arrested if the steel plate used for the flange had a high K _ca value in the range from 4900 to 7300 N/mm^3/2. FEM analysis of the stress intensity factor K indicated that brittle crack propagation was arrested under the condition that the K value at the running crack tip was less than the K _ca of the material. In the T-joint, it was noted that the K value around the deepest point of the crack decreased and was finally less than the K _ca of the flange plate when the brittle crack penetrated into the flange plate. This phenomenon shows the advantage of using a T-joint for brittle crack arrest in the flange plates of Strength Deck structures. In order to verify the long brittle crack arrestability of the T-joint structure, ultra-large-scale tests were carried out under the recommended conditions obtained from a dynamic FEM analysis. The test results showed that long brittle cracks could arrest at the aforementioned T-joint structures.
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Brittle Crack Propagation/Arrest Behavior in T-Joint Structure of Heavy Gauge Steel Plates
Materials Science Forum, 2012Co-Authors: Tsunehisa Handa, Kimihiro Nishimura, Hiroshi Shiomi, Seishi TsuyamaAbstract:Brittle crack arrestability is extremely important in welded joints of heavy gauge steel plates used in large container ships. Recently, much attention has been focused on potential crack propagation along welds using large heat input. This paper examines the application of a T-joint to the Strength Deck structure of container ships to enhance crack arrestability. The crack arrest toughness, Kca, for crack arrest was varied. The ESSO test of T-joint components showed that brittle crack was arrested at the T-joint if the steel plate used for the flange had a high Kca value in the range from 4900 to 7300N/mm3/2. FE-analysis of the stress intensity factor K indicated that brittle crack propagation was arrested under the condition that the K-value at the running crack tip was less than the Kca of the material. In the T-joint, it was noted that the K-value around the area of the deepest point of the crack decreased and was finally less than the Kca of the flange plate when the brittle crack penetrated suddenly into the flange plate to a 10mm depth. This phenomenon shows the advantage of using a T-joint for brittle crack arrest in the flange plates of Strength Deck structures.
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Effect of unwelded length on behaviour of brittle crack arrest in T-joint structure
Welding International, 2009Co-Authors: Tsunehisa Handa, Masanobu Toyoda, Shinichi Suzuki, Noboru Kiji, Takashi MiyataAbstract:In the large heat input weld joint of heavy gauge steel plate used for large container carriers, a brittle crack possibly propagates straight along a weld joint without diverging to the base metal. This phenomenon is discussed for its application to the large heat input weld of heavy gauge plate to ship structures. In this study, to arrest a brittle crack at the T-joint embedding unwelded face, the effect of the unwelded face on behaviour of brittle crack propagation/arrest in the T-joint structure was investigated and analysed. The ESSO test of the T-joint structure was carried out, supposing that a brittle crack which propagates along a weld joint of hatch coaming rush into T-joint of hatch coaming and Strength Deck. The test results showed that the brittle crack arrested at the T-joint embedding the unwelded face, and the brittle crack arrested easier, the longer the unwelded face. The results of static FEM analysis showed that the stress intensity factor of the brittle crack was increased by the unwel...
Fumiyoshi Minami - One of the best experts on this subject based on the ideXlab platform.
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Brittle Crack Propagation/Arrest Behavior in Full Penetration T-joint
Journal of the Japan Society of Naval Architects and Ocean Engineers, 2020Co-Authors: Tsunehisa Handa, Kimihiro Nishimura, Testuya Tagawa, Kenji Oi, Fumiyoshi MinamiAbstract:Arrestability of brittle cracks is extremely important in the structural integrity of welded joints of heavy gauge steel plates used in large container ships. Recently, a great attention has been focused on potential crack propagation along welds made with large heat input. In this study, a T-joint is applied to the Strength Deck structure of container ships to enhance crack arrestability. Material crack arrest toughnesses, Kca, of some steel plates are varied. The ESSO tests of T-joint components showed that a brittle crack is arrested at the T-joint if the steel plate used in the flange has a high Kca value in the range from 4900 to 7300 N/mm ³/². Finite element (FE)-analyses of the stress intensity factor K indicated that brittle crack propagation is arrested under the condition that the K-value at the running crack tip is less than the Kca of the material. It is noted in the T-joint that the K-value at the deepest point of the crack decreases and is finally below the Kca of the flange plate when a brittle crack rapidly penetrates the flange plate to a depth of 30-40mm. These phenomena show the advantage of the T-joint in brittle crack arrestability in the flange plate of the Strength Deck structure.
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Brittle crack propagation/arrest behavior in T-joint structure of heavy gauge steel plate
Welding in the World, 2015Co-Authors: Tsunehisa Handa, Kenji Oi, Tetsuya Tagawa, Fumiyoshi MinamiAbstract:Brittle crack arrestability is extremely important in welded joints of heavy gauge steel plates used in large container ships. Recently, much attention has been focused on potential crack propagation along welds fabricated by large heat input welding. This paper examines the application of a T-joint to the Strength Deck structure of container ships to enhance crack arrestability. The unwelded face and the crack arrest toughness, K _ca, for crack arrest were varied. In the case of a T-joint with an unwelded face, the ESSO test of the T-joint components showed that a brittle crack arrested at the T-joint embedding the unwelded face. In the case of a full penetration T-joint, the brittle crack was arrested if the steel plate used for the flange had a high K _ca value in the range from 4900 to 7300 N/mm^3/2. FEM analysis of the stress intensity factor K indicated that brittle crack propagation was arrested under the condition that the K value at the running crack tip was less than the K _ca of the material. In the T-joint, it was noted that the K value around the deepest point of the crack decreased and was finally less than the K _ca of the flange plate when the brittle crack penetrated into the flange plate. This phenomenon shows the advantage of using a T-joint for brittle crack arrest in the flange plates of Strength Deck structures. In order to verify the long brittle crack arrestability of the T-joint structure, ultra-large-scale tests were carried out under the recommended conditions obtained from a dynamic FEM analysis. The test results showed that long brittle cracks could arrest at the aforementioned T-joint structures.
Seishi Tsuyama - One of the best experts on this subject based on the ideXlab platform.
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Brittle Crack Propagation/Arrest Behavior in T-Joint Structure of Heavy Gauge Steel Plates
Materials Science Forum, 2012Co-Authors: Tsunehisa Handa, Kimihiro Nishimura, Hiroshi Shiomi, Seishi TsuyamaAbstract:Brittle crack arrestability is extremely important in welded joints of heavy gauge steel plates used in large container ships. Recently, much attention has been focused on potential crack propagation along welds using large heat input. This paper examines the application of a T-joint to the Strength Deck structure of container ships to enhance crack arrestability. The crack arrest toughness, Kca, for crack arrest was varied. The ESSO test of T-joint components showed that brittle crack was arrested at the T-joint if the steel plate used for the flange had a high Kca value in the range from 4900 to 7300N/mm3/2. FE-analysis of the stress intensity factor K indicated that brittle crack propagation was arrested under the condition that the K-value at the running crack tip was less than the Kca of the material. In the T-joint, it was noted that the K-value around the area of the deepest point of the crack decreased and was finally less than the Kca of the flange plate when the brittle crack penetrated suddenly into the flange plate to a 10mm depth. This phenomenon shows the advantage of using a T-joint for brittle crack arrest in the flange plates of Strength Deck structures.
Kenji Oi - One of the best experts on this subject based on the ideXlab platform.
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Brittle Crack Propagation/Arrest Behavior in Full Penetration T-joint
Journal of the Japan Society of Naval Architects and Ocean Engineers, 2020Co-Authors: Tsunehisa Handa, Kimihiro Nishimura, Testuya Tagawa, Kenji Oi, Fumiyoshi MinamiAbstract:Arrestability of brittle cracks is extremely important in the structural integrity of welded joints of heavy gauge steel plates used in large container ships. Recently, a great attention has been focused on potential crack propagation along welds made with large heat input. In this study, a T-joint is applied to the Strength Deck structure of container ships to enhance crack arrestability. Material crack arrest toughnesses, Kca, of some steel plates are varied. The ESSO tests of T-joint components showed that a brittle crack is arrested at the T-joint if the steel plate used in the flange has a high Kca value in the range from 4900 to 7300 N/mm ³/². Finite element (FE)-analyses of the stress intensity factor K indicated that brittle crack propagation is arrested under the condition that the K-value at the running crack tip is less than the Kca of the material. It is noted in the T-joint that the K-value at the deepest point of the crack decreases and is finally below the Kca of the flange plate when a brittle crack rapidly penetrates the flange plate to a depth of 30-40mm. These phenomena show the advantage of the T-joint in brittle crack arrestability in the flange plate of the Strength Deck structure.
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Brittle crack propagation/arrest behavior in T-joint structure of heavy gauge steel plate
Welding in the World, 2015Co-Authors: Tsunehisa Handa, Kenji Oi, Tetsuya Tagawa, Fumiyoshi MinamiAbstract:Brittle crack arrestability is extremely important in welded joints of heavy gauge steel plates used in large container ships. Recently, much attention has been focused on potential crack propagation along welds fabricated by large heat input welding. This paper examines the application of a T-joint to the Strength Deck structure of container ships to enhance crack arrestability. The unwelded face and the crack arrest toughness, K _ca, for crack arrest were varied. In the case of a T-joint with an unwelded face, the ESSO test of the T-joint components showed that a brittle crack arrested at the T-joint embedding the unwelded face. In the case of a full penetration T-joint, the brittle crack was arrested if the steel plate used for the flange had a high K _ca value in the range from 4900 to 7300 N/mm^3/2. FEM analysis of the stress intensity factor K indicated that brittle crack propagation was arrested under the condition that the K value at the running crack tip was less than the K _ca of the material. In the T-joint, it was noted that the K value around the deepest point of the crack decreased and was finally less than the K _ca of the flange plate when the brittle crack penetrated into the flange plate. This phenomenon shows the advantage of using a T-joint for brittle crack arrest in the flange plates of Strength Deck structures. In order to verify the long brittle crack arrestability of the T-joint structure, ultra-large-scale tests were carried out under the recommended conditions obtained from a dynamic FEM analysis. The test results showed that long brittle cracks could arrest at the aforementioned T-joint structures.
Kimihiro Nishimura - One of the best experts on this subject based on the ideXlab platform.
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Brittle Crack Propagation/Arrest Behavior in Full Penetration T-joint
Journal of the Japan Society of Naval Architects and Ocean Engineers, 2020Co-Authors: Tsunehisa Handa, Kimihiro Nishimura, Testuya Tagawa, Kenji Oi, Fumiyoshi MinamiAbstract:Arrestability of brittle cracks is extremely important in the structural integrity of welded joints of heavy gauge steel plates used in large container ships. Recently, a great attention has been focused on potential crack propagation along welds made with large heat input. In this study, a T-joint is applied to the Strength Deck structure of container ships to enhance crack arrestability. Material crack arrest toughnesses, Kca, of some steel plates are varied. The ESSO tests of T-joint components showed that a brittle crack is arrested at the T-joint if the steel plate used in the flange has a high Kca value in the range from 4900 to 7300 N/mm ³/². Finite element (FE)-analyses of the stress intensity factor K indicated that brittle crack propagation is arrested under the condition that the K-value at the running crack tip is less than the Kca of the material. It is noted in the T-joint that the K-value at the deepest point of the crack decreases and is finally below the Kca of the flange plate when a brittle crack rapidly penetrates the flange plate to a depth of 30-40mm. These phenomena show the advantage of the T-joint in brittle crack arrestability in the flange plate of the Strength Deck structure.
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Brittle Crack Propagation/Arrest Behavior in T-Joint Structure of Heavy Gauge Steel Plates
Materials Science Forum, 2012Co-Authors: Tsunehisa Handa, Kimihiro Nishimura, Hiroshi Shiomi, Seishi TsuyamaAbstract:Brittle crack arrestability is extremely important in welded joints of heavy gauge steel plates used in large container ships. Recently, much attention has been focused on potential crack propagation along welds using large heat input. This paper examines the application of a T-joint to the Strength Deck structure of container ships to enhance crack arrestability. The crack arrest toughness, Kca, for crack arrest was varied. The ESSO test of T-joint components showed that brittle crack was arrested at the T-joint if the steel plate used for the flange had a high Kca value in the range from 4900 to 7300N/mm3/2. FE-analysis of the stress intensity factor K indicated that brittle crack propagation was arrested under the condition that the K-value at the running crack tip was less than the Kca of the material. In the T-joint, it was noted that the K-value around the area of the deepest point of the crack decreased and was finally less than the Kca of the flange plate when the brittle crack penetrated suddenly into the flange plate to a 10mm depth. This phenomenon shows the advantage of using a T-joint for brittle crack arrest in the flange plates of Strength Deck structures.
