The Experts below are selected from a list of 180 Experts worldwide ranked by ideXlab platform
Aditya Rio Prabowo - One of the best experts on this subject based on the ideXlab platform.
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Analysis of structural behavior during collision event accounting for bow and side structure interaction
Theoretical and Applied Mechanics Letters, 2020Co-Authors: Aditya Rio Prabowo, Jung Min Sohn, Ahmad Fauzan Zakki, Qing WangAbstract:Abstract The main goal of this study was to investigate the effects of selected Ship collision parameter values on the characteristics of the absorbed energy in several Ship collision scenarios. Non-linear simulations were performed using a finite element method (FEM) to obtain virtual experiment data. In the present research, the size of the side damage from a collision phenomenon were measured and used to verify the numerical configuration together with the calculation results using an empirical equation. Parameters in the external dynamics of a Ship collision such as the location of the contact point and velocity of the Striking Ship were taken into consideration. The internal energy and deformation size on the side structure were discussed further in a comparative study. The effects of the selected parameters on several structural behaviors, namely energy, force, and damage extent were also observed and evaluated in this section. Stiffener on side hull was found to contribute significantly into resistance capability of the target Ship against penetration of the Striking bow. Remarkable force during penetration was observed to occur when inner shell was crushed as certain velocity was applied in the Striking bow.
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Investigation on the Structural Damage of a Double-Hull Ship, Part I – Ship Collision
Procedia structural integrity, 2020Co-Authors: Aditya Rio Prabowo, Seung Jun Baek, Jung Hoon Byeon, Jung Min SohnAbstract:Abstract Marine structure is designed to be able to resist various load conditions during its operational period. However, in design process, analysis of accidental loads, such collision and grounding, has not been included for both merchant Ship and navy vessel. These loads are spontaneous and several remarkable casualties may occur after collision and grounding taking place. The aim of this paper is to investigate structural damage on the target Ship during collision and grounding considering on failure process and damage extent. This work is divided into two parts which in the Part I, Ship collision is discussed, and the Part II deals with interaction of Ship structure with sea bottom in grounding. In the Part I - Ship Collision, condition of the side structure is observed, including the inner hull after impact which is considered as the key to determine safety condition of Ship cargo. A passenger Ship is modelled in this work and designated as the struck Ship which will be struck by the Striking Ship in collision process. Resistance capability of the double-hull structure against side collision is evaluated. Virtual experiment is conducted by nonlinear finite element method in order to calculate several dynamic collision scenarios which are built based on physical parameter, namely target location. Based on calculation results, damage on the side hull is found to be highly influenced by relative height between two Ships prior collision. Crashworthiness criteria are summarized and result tendency indicates that in the mentioned location, the Striking Ship produces larger tearing on the lower part of the struck Ship. Contribution of each collision scenario on the resultant force is presented in later part in order to observe structural behaviour of each determined location in encountering side collision.
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Progressive structural failure of the RoRo side hull during accidental powered-bow collisions
2018Co-Authors: Aditya Rio Prabowo, Jung Min Sohn, Bangun Ir Harsritanto, Aldias Bahatmaka, Samuel SamuelAbstract:Contact phenomena can be advantageous in several activities, such as material forming for a hull plate of a Ship in Shipbuilding. However in ocean engineering and marine structure, sometimes contact cannot be controlled and produces an impact which causes immense casualties for Ship, crew, cargo and sea environment. Collision appears as the most common impact form which its influence to destruction of a sea environment has been acknowledged. In this study, a concern is addressed to a structural observation under a Ship collision. A side structure of a passenger Ship is modelled to be the target Ship while the other Ship so called the Striking Ship is deployed as an indenter to penetrate the target Ship. Results indicate that the interactions in contact process involve not only the upper deck but also the bulbous bow of the Striking Ship. Load and draught height of the Striking Ship can change which lead to a change of impact target and deformation on the target Ship. Finally, the confirmation of energy that is used to destroy the struck Ship is summarized.Contact phenomena can be advantageous in several activities, such as material forming for a hull plate of a Ship in Shipbuilding. However in ocean engineering and marine structure, sometimes contact cannot be controlled and produces an impact which causes immense casualties for Ship, crew, cargo and sea environment. Collision appears as the most common impact form which its influence to destruction of a sea environment has been acknowledged. In this study, a concern is addressed to a structural observation under a Ship collision. A side structure of a passenger Ship is modelled to be the target Ship while the other Ship so called the Striking Ship is deployed as an indenter to penetrate the target Ship. Results indicate that the interactions in contact process involve not only the upper deck but also the bulbous bow of the Striking Ship. Load and draught height of the Striking Ship can change which lead to a change of impact target and deformation on the target Ship. Finally, the confirmation of energy th...
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Finite element analysis for estimating steel structure responses under a variety of marine-collision actions
International Journal of Earthquake and Impact Engineering, 2018Co-Authors: Aditya Rio Prabowo, Jung Min Sohn, Ahmad Fauzan Zakki, Seung Jun Baek, Jung Hoon Byeon, Gunawan Dwi Haryadi, Bangun Ir HarsritantoAbstract:This study conducted a series of Ship collision analyses to observe the effect of external parameters on the responses of steel structures. Variations in mass are represented by using different Ship types as the Striking Ship, while an oblique collision was conducted initially and was compared to a perpendicular collision scenario. The other involved Ship was denoted as the struck Ship, and the side structures of a RoRo passenger Ship were designated as the target. Crashworthiness criteria produced by the finite element analysis can be summarised to illustrate the trends in structural responses for the selected parameters. Based on this summary of the FE solutions, satisfactory results were obtained, as the rigid Striking Ship successfully produced a higher internal energy. In terms of the damage extent, the larger dimensions of the cargo carrier as the Striking Ship (compared to the struck Ship) significantly crushed the target structure.
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Performance assessment on a variety of double side structure during collision interaction with other Ship
Curved and Layered Structures, 2017Co-Authors: Aditya Rio Prabowo, Jung Min SohnAbstract:Abstract The main goal of the present paper was to study the physical response of a double side skin (DSS) structure under impact load in a collision event between two Ships. Collision energy and damage extent (size and location) during the collision process were observed together with damage patterns on side structure. The Ships were modeled after a Ro-Ro passenger Ship and cargo reefer which were involved in a Ship collision on the Sunda Strait while the analyseswere performed using non-linear simulations FEMto produce virtual simulation data. Several caseswere proposed to be investigated in this work with involvement of parameters i.e. penetration location and Ship materials which were embedded on the structure model. A series of material experiments and testing was conducted to obtain detailed material properties which were to be deployed in simulation. It was shown that, after penetration at the transition location, the Striking Ship was successfully deforming and forming tears to the inner skin. On the other hand, with identical structure and identical mass of construction, the use of high-strength low-alloy (HSLA) steel as the repair material offered considerably better capacity in absorbing the impact load than plain-carbon steel.
Jung Min Sohn - One of the best experts on this subject based on the ideXlab platform.
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Analysis of structural behavior during collision event accounting for bow and side structure interaction
Theoretical and Applied Mechanics Letters, 2020Co-Authors: Aditya Rio Prabowo, Jung Min Sohn, Ahmad Fauzan Zakki, Qing WangAbstract:Abstract The main goal of this study was to investigate the effects of selected Ship collision parameter values on the characteristics of the absorbed energy in several Ship collision scenarios. Non-linear simulations were performed using a finite element method (FEM) to obtain virtual experiment data. In the present research, the size of the side damage from a collision phenomenon were measured and used to verify the numerical configuration together with the calculation results using an empirical equation. Parameters in the external dynamics of a Ship collision such as the location of the contact point and velocity of the Striking Ship were taken into consideration. The internal energy and deformation size on the side structure were discussed further in a comparative study. The effects of the selected parameters on several structural behaviors, namely energy, force, and damage extent were also observed and evaluated in this section. Stiffener on side hull was found to contribute significantly into resistance capability of the target Ship against penetration of the Striking bow. Remarkable force during penetration was observed to occur when inner shell was crushed as certain velocity was applied in the Striking bow.
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Investigation on the Structural Damage of a Double-Hull Ship, Part I – Ship Collision
Procedia structural integrity, 2020Co-Authors: Aditya Rio Prabowo, Seung Jun Baek, Jung Hoon Byeon, Jung Min SohnAbstract:Abstract Marine structure is designed to be able to resist various load conditions during its operational period. However, in design process, analysis of accidental loads, such collision and grounding, has not been included for both merchant Ship and navy vessel. These loads are spontaneous and several remarkable casualties may occur after collision and grounding taking place. The aim of this paper is to investigate structural damage on the target Ship during collision and grounding considering on failure process and damage extent. This work is divided into two parts which in the Part I, Ship collision is discussed, and the Part II deals with interaction of Ship structure with sea bottom in grounding. In the Part I - Ship Collision, condition of the side structure is observed, including the inner hull after impact which is considered as the key to determine safety condition of Ship cargo. A passenger Ship is modelled in this work and designated as the struck Ship which will be struck by the Striking Ship in collision process. Resistance capability of the double-hull structure against side collision is evaluated. Virtual experiment is conducted by nonlinear finite element method in order to calculate several dynamic collision scenarios which are built based on physical parameter, namely target location. Based on calculation results, damage on the side hull is found to be highly influenced by relative height between two Ships prior collision. Crashworthiness criteria are summarized and result tendency indicates that in the mentioned location, the Striking Ship produces larger tearing on the lower part of the struck Ship. Contribution of each collision scenario on the resultant force is presented in later part in order to observe structural behaviour of each determined location in encountering side collision.
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Progressive structural failure of the RoRo side hull during accidental powered-bow collisions
2018Co-Authors: Aditya Rio Prabowo, Jung Min Sohn, Bangun Ir Harsritanto, Aldias Bahatmaka, Samuel SamuelAbstract:Contact phenomena can be advantageous in several activities, such as material forming for a hull plate of a Ship in Shipbuilding. However in ocean engineering and marine structure, sometimes contact cannot be controlled and produces an impact which causes immense casualties for Ship, crew, cargo and sea environment. Collision appears as the most common impact form which its influence to destruction of a sea environment has been acknowledged. In this study, a concern is addressed to a structural observation under a Ship collision. A side structure of a passenger Ship is modelled to be the target Ship while the other Ship so called the Striking Ship is deployed as an indenter to penetrate the target Ship. Results indicate that the interactions in contact process involve not only the upper deck but also the bulbous bow of the Striking Ship. Load and draught height of the Striking Ship can change which lead to a change of impact target and deformation on the target Ship. Finally, the confirmation of energy that is used to destroy the struck Ship is summarized.Contact phenomena can be advantageous in several activities, such as material forming for a hull plate of a Ship in Shipbuilding. However in ocean engineering and marine structure, sometimes contact cannot be controlled and produces an impact which causes immense casualties for Ship, crew, cargo and sea environment. Collision appears as the most common impact form which its influence to destruction of a sea environment has been acknowledged. In this study, a concern is addressed to a structural observation under a Ship collision. A side structure of a passenger Ship is modelled to be the target Ship while the other Ship so called the Striking Ship is deployed as an indenter to penetrate the target Ship. Results indicate that the interactions in contact process involve not only the upper deck but also the bulbous bow of the Striking Ship. Load and draught height of the Striking Ship can change which lead to a change of impact target and deformation on the target Ship. Finally, the confirmation of energy th...
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Finite element analysis for estimating steel structure responses under a variety of marine-collision actions
International Journal of Earthquake and Impact Engineering, 2018Co-Authors: Aditya Rio Prabowo, Jung Min Sohn, Ahmad Fauzan Zakki, Seung Jun Baek, Jung Hoon Byeon, Gunawan Dwi Haryadi, Bangun Ir HarsritantoAbstract:This study conducted a series of Ship collision analyses to observe the effect of external parameters on the responses of steel structures. Variations in mass are represented by using different Ship types as the Striking Ship, while an oblique collision was conducted initially and was compared to a perpendicular collision scenario. The other involved Ship was denoted as the struck Ship, and the side structures of a RoRo passenger Ship were designated as the target. Crashworthiness criteria produced by the finite element analysis can be summarised to illustrate the trends in structural responses for the selected parameters. Based on this summary of the FE solutions, satisfactory results were obtained, as the rigid Striking Ship successfully produced a higher internal energy. In terms of the damage extent, the larger dimensions of the cargo carrier as the Striking Ship (compared to the struck Ship) significantly crushed the target structure.
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Performance assessment on a variety of double side structure during collision interaction with other Ship
Curved and Layered Structures, 2017Co-Authors: Aditya Rio Prabowo, Jung Min SohnAbstract:Abstract The main goal of the present paper was to study the physical response of a double side skin (DSS) structure under impact load in a collision event between two Ships. Collision energy and damage extent (size and location) during the collision process were observed together with damage patterns on side structure. The Ships were modeled after a Ro-Ro passenger Ship and cargo reefer which were involved in a Ship collision on the Sunda Strait while the analyseswere performed using non-linear simulations FEMto produce virtual simulation data. Several caseswere proposed to be investigated in this work with involvement of parameters i.e. penetration location and Ship materials which were embedded on the structure model. A series of material experiments and testing was conducted to obtain detailed material properties which were to be deployed in simulation. It was shown that, after penetration at the transition location, the Striking Ship was successfully deforming and forming tears to the inner skin. On the other hand, with identical structure and identical mass of construction, the use of high-strength low-alloy (HSLA) steel as the repair material offered considerably better capacity in absorbing the impact load than plain-carbon steel.
Philippe Rigo - One of the best experts on this subject based on the ideXlab platform.
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Ship collision analysis on Offshore Wind Turbine monopile foundations
Marine Structures, 2020Co-Authors: Andreea Bela, Hervé Le Sourne, Loïc Buldgen, Philippe RigoAbstract:Abstract An offshore wind farm can be located close to traffic lanes of commercial and passenger Ships, which may lead to possible collision. The work presented in this paper aims to understand both the crushing behaviour and the nacelle dynamics of a monopile offshore wind turbine when impacted by a Ship. Another objective was to deeply investigate the influence of various parameters like Ship impact velocity and location, wind direction, soil stiffness and deformability of the Striking Ship. First, nonlinear numerical simulations of Ship - Offshore Wind Turbine (OWT) collisions have been carried out with a rigid Striking Ship for a better understanding of the OWT's structural behaviour during collision. Different configurations for the wind turbine's structure have been used in order to highlight the modifications in behaviour induced by changing the soil conditions or the loading scenario. The resulting resistant force and internal energies have been compared as well as the tower top (nacelle) displacements and accelerations. Then, another series of simulations have been performed with a deformable Ship in order to investigate the influence of the deformability of the Striking Ship on the OWT's behaviour. It was shown that a slight variation of the impact velocity can lead to consequences ranging from minor damage of the OWT to collapse. Furthermore, the behaviour of the OWT during collision is highly sensitive to wind loads as it was shown that in some cases the OWT can collapse for an impact velocity of only 3 m/s and, in the worst case, can fall directly on the Ship. The results obtained showed that it is important to account for the soil flexibility when performing collision simulations because considering the monopile as being clamped at the base would lead to an overestimation of the plastic deformation of the collided structure. Moreover, when the OWT is collided by a deformable Striking Ship, the deformations of the OWT are 2 times smaller comparing to the deformations caused by impact with a rigid Ship and the structure can withstand collisions without collapsing with an impact velocity up to 6 m/s.
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Numerical crashworthiness analysis of an offshore wind turbine monopile impacted by a Ship
Journal of Marine Science and Technology, 2015Co-Authors: Andreea Bela, Hervé Le Sourne, Loïc Buldgen, Philippe RigoAbstract:The objective of the present work is to understand the crushing behavior of a predefined wind turbine jacket when it is impacted by a Ship. To investigate the resulting deformation modes and the repartition of dissipated energy, nonlinear finite element analyses are performed to simulate both rigid and deformable Ships colliding the jacket at different velocities. In a first part, a sensitivity analysis to the jacket impacted area is carried out to find the most damaging situation. Then, the influences of gravity loads, wind force, and soil stiffness are studied, considering that the Striking Ship is rigid. In a second part, the jacket is supposed to be collided by two different deformable vessels and the internal energy distribution between the jacket and the Striking Ships is analyzed for different jacket leg thicknesses. Some numerical analyses focus also on the transfer of the crushing force between the impacted leg to the others through the braces. All these numerical results will further serve to fix the hypotheses for the development of a simplified tool based on analytical formulations.
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A simplified analytical method for estimating the crushing resistance of an inclined Ship side
Marine Structures, 2013Co-Authors: Loïc Buldgen, Hervé Le Sourne, Philippe RigoAbstract:Abstract This paper provides a new contribution to the simplified analytical treatment of collisions between two Ships. It is directly connected to the well-known super-elements method, which is a simplified procedure allowing for a quick estimation of the damages caused to both the Striking and struck vessels during such events. In this article, a new analytical formulation is presented for estimating the impact resistance provided by inclined Ship side panels. Two different scenarios are treated. We first deal with the case of an impact between the oblique plate and the stem of the Striking Ship, and then we consider the situation where the inclined panel is impacted by the bulb. For these two scenarios, an analytical formulation relating the force and the penetration is provided and these developments are validated by comparing them to the results of finite elements simulations. Finally, the new inclined plate super-element is integrated in a simplified model of a frigate collided by another Ship, and the resistance given by the super-elements method is then compared to the one obtained by a numerical simulation of this collision.
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Simplified Analytical Method for Estimating the Resistance of Lock Gates to Ship Impacts
Journal of Applied Mathematics, 2012Co-Authors: Loïc Buldgen, Hervé Le Sourne, Philippe RigoAbstract:The present paper is concerned with the design of lock gates submitted to Ship impacts. In this paper, a simplified analytical method is presented to evaluate the resistance of such structures under collision. The basic idea is to assume that the resistance is first provided through a local deforming mode, corresponding to a localized crushing of some impacted structural elements. For consecutive larger deformations, the resistance is then mostly provided through a global deforming mode, corresponding to an overall movement of the entire gate. For assessing the resistance in the case of the local deforming mode, the structure is divided into a given number of large structural entities called “superelements.” For each of them, a relation between the resistance of the gate and the penetration of the Striking Ship is established. However, as some results are already available in the literature, this subject is not treated extensively in this paper. On the contrary, the calculation of the resistance of the gate provided through the global mode is detailed and the strategy to switch from local to global deformation is highlighted. Finally, we propose to validate our developments by making a comparison between results obtained numerically and those predicted by the present analytical approach.
Ahmad Fauzan Zakki - One of the best experts on this subject based on the ideXlab platform.
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Analysis of structural behavior during collision event accounting for bow and side structure interaction
Theoretical and Applied Mechanics Letters, 2020Co-Authors: Aditya Rio Prabowo, Jung Min Sohn, Ahmad Fauzan Zakki, Qing WangAbstract:Abstract The main goal of this study was to investigate the effects of selected Ship collision parameter values on the characteristics of the absorbed energy in several Ship collision scenarios. Non-linear simulations were performed using a finite element method (FEM) to obtain virtual experiment data. In the present research, the size of the side damage from a collision phenomenon were measured and used to verify the numerical configuration together with the calculation results using an empirical equation. Parameters in the external dynamics of a Ship collision such as the location of the contact point and velocity of the Striking Ship were taken into consideration. The internal energy and deformation size on the side structure were discussed further in a comparative study. The effects of the selected parameters on several structural behaviors, namely energy, force, and damage extent were also observed and evaluated in this section. Stiffener on side hull was found to contribute significantly into resistance capability of the target Ship against penetration of the Striking bow. Remarkable force during penetration was observed to occur when inner shell was crushed as certain velocity was applied in the Striking bow.
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Finite element analysis for estimating steel structure responses under a variety of marine-collision actions
International Journal of Earthquake and Impact Engineering, 2018Co-Authors: Aditya Rio Prabowo, Jung Min Sohn, Ahmad Fauzan Zakki, Seung Jun Baek, Jung Hoon Byeon, Gunawan Dwi Haryadi, Bangun Ir HarsritantoAbstract:This study conducted a series of Ship collision analyses to observe the effect of external parameters on the responses of steel structures. Variations in mass are represented by using different Ship types as the Striking Ship, while an oblique collision was conducted initially and was compared to a perpendicular collision scenario. The other involved Ship was denoted as the struck Ship, and the side structures of a RoRo passenger Ship were designated as the target. Crashworthiness criteria produced by the finite element analysis can be summarised to illustrate the trends in structural responses for the selected parameters. Based on this summary of the FE solutions, satisfactory results were obtained, as the rigid Striking Ship successfully produced a higher internal energy. In terms of the damage extent, the larger dimensions of the cargo carrier as the Striking Ship (compared to the struck Ship) significantly crushed the target structure.
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Analysis of structural damage on the struck Ship under side collision scenario
alexandria engineering journal, 2017Co-Authors: Aditya Rio Prabowo, Jung Min Sohn, Ahmad Fauzan Zakki, Qing WangAbstract:Abstract The occurrence of impact needs to be predicted for various cases as it mostly delivers negative to target object and environment. In marine structure, this phenomenon has distributed numerous damages to involved objects, such as can be found in tragedy of the Estonia in 1994. This disaster led to a reassessment of the safety of passenger Ships in many country. During impact both of structural and material aspects contributes to responses in form of energy, force, and damage. In present work, consideration of the both aspects would be considered in preparation, analysis, and discussion, to evaluate contribution of considered aspects on failure characteristic. A target subjected to impact load in form of collision so called struck Ship which had different hull configuration would be used in analysis as structural behaviour during and after hull structure of the struck Ship was penetrated by the Striking Ship would be observed. In material level, analyses were conducted with applying different mechanical properties on the side structure. The results indicated that the tearing of inner hull was avoided due to size of double hull structure. This condition provided better safety but lower Ship capacity. In other hand, strength characteristic of material was proofed dominate difference of internal energy. Finally, the influences of material strength, failure strain, and hardening parameter were evaluated and summarized.
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effects of the rebounding of a Striking Ship on structural crashworthiness during Ship Ship collision
Thin-walled Structures, 2017Co-Authors: Aditya Rio Prabowo, Jung Min Sohn, Ahmad Fauzan ZakkiAbstract:Abstract The purpose of this paper is to study the rebounding phenomenon of a Striking Ship and its effect on the structural crashworthiness of the struck Ship. Pioneer works on Ship collision and mathematical formulations to assess energy after collision are described to summarize the behaviour of the Ship structure under collision between Ships in various scenarios. A benchmark study is conducted using laboratory tests of the resistance to penetration of a stiffened plate to validate the methodology of the present work, which uses finite element methods to model a series of dynamic collision scenarios. The setting and configuration of a full-scale collision analysis is introduced, along with the configurations of the defined scenarios. External and internal Ship collision parameters are considered as parameters that will affect structural behaviour prior to and after ruptures. The results of the evaluation indicate that in the event of a side collision, the Striking Ship can either fully stuck or rebounding phenomena. These phenomena produce significant differences in term of internal energy and crushing force, which are included as crashworthiness criteria. The type of Striking Ship, as well as its velocity, significantly affects the rebounding of the Striking Ship and behaviour of the struck Ship. A notable gap between medium and high-carbon steels is not found during observations of the structural crashworthiness accounting for structure materials. Finally, other criteria for assessing the mechanisms and effects of rebounding during a collision are summarized, i.e. kinetic energy, acceleration, and extent of damage.
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Rapid prediction of damage on a struck Ship accounting for side impact scenario models
Open Engineering, 2017Co-Authors: Aditya Rio Prabowo, Jung Min Sohn, Ahmad Fauzan ZakkiAbstract:AbstractThe impact phenomenon is inseparable part of every physical things, from substantial particle until macrostructure namely Ship. In Ship collisions, short-period load is distributed during impact process from Striking Ship into struck Ship. The kinetic energy that is used to move Striking Ship is absorbed by struck Ship that makes its structure undergoes plastic deformation and failure. This paper presents study that focuses on predicting occurred damage on side hull of struck Ship for various impact scenario models. These scenarios are calculated by finite element approach to obtain characteristic on damage, energy as well as load during and after impact processes. The results indicate that the damages on impact to longitudinal components such as main and car decks are smaller than impact to transverse structure components. The damage and deformation are widely distributed to almost side structures including inner structure. The width between outer and inner shells is very affecting the damage mode where the width below the two meters will make inner shell experience damage beyond plastic deformation. The contribution of structure components is proofed deliver significant effect to damage mode and material strengths clearly affect the results in energy and load characteristic.
Jeom Kee Paik - One of the best experts on this subject based on the ideXlab platform.
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On accidental limit state design of spherical type LNG carrier structures against Ship collisions
2020Co-Authors: Jeom Kee Paik, Ick Hung Choe, Anil Kumar ThayamballiAbstract:The modem design of steel structures uses limit states classified into four types, namely serviceability limit state, ultimate limit state, fatigue limit state and accidental limit state. The aim of this paper is to fill an important existing design need, by proposing and illustrating a procedure to confirm that the accidental limit state based safety level of a spherical type LNG carrier designed to carry liquefied natural gas of 135,000 m 3 capacity is sufficient against Ship collisions. An assessment procedure based on the energy dissipation capability relating to structural crashworthiness can in this case be applied to protect spherical LNG cargo tanks from fracture in minor or moderate collision accidents as shown in the paper. In the procedures developed, while the loss of kinetic energy during the collision accident is approximately estimated by applying the momentum equilibrium of the two implicated Ships, a series of relatively sophisticated numerical computations are undertaken to simulate the structural crashworthiness of the object Ship in the full load condition at standstill, varying the loading conditions and types of the Striking Ship, when the LNG carrier side structure is considered to be struck by the bow of either a VLCC or another LNG carrier. Based on the computed results, the collision resistance indices (CRI), which in the present study are defined as a function of the ratio of the structural energy dissipation capability to the initial kinetic energy loss are calculated for the object Ship for various collision scenarios. Some important insights useful for preventing collision damage of the spherical LNG cargo tanks of the Ship are also discussed.
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effects of a deformable Striking Ship s bow on the structural crashworthiness in Ship Ship collisions
Ships and Offshore Structures, 2018Co-Authors: Yeong Gook Ko, Jeom Kee PaikAbstract:ABSTRACTShip–Ship collision accidents continue to occur regardless of the continuous efforts to prevent them, and they essentially involve highly nonlinear problems associated with structural crash...
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Predicting Resistance of Spherical-Type LNG Carrier Structures to Ship Collisions
Marine Technology and Sname News, 2002Co-Authors: Jeom Kee Paik, Ick Hung Choe, Anil Kumar ThayamballiAbstract:The modern design of steel structures uses limit states classified into four types, namely, serviceability limit state, ultimate limit state, fatigue limit state and accidental limit state. The aim of this paper is to propose and illustrate a procedure to assess the capability of a spherical-type LNG carrier of 135 000 m 3 to resist Ship collisions. An assessment procedure based on the energy dissipation capability relating to structural crashworthiness can, in this case, be applied to protect spherical LNG cargo tanks from fracture in minor or moderate collision accidents as shown in the paper. In the procedures developed, while the loss of kinetic energy during the collision accident is approximately estimated by applying the momentum equilibrium of the two implicated Ships, a series of relatively sophisticated numerical computations is undertaken to simulate the structural crashworthiness of the object Ship in the full load condition at standstill, varying the loading conditions and types of the Striking Ship, when the LNG carrier side structure is considered to be struck by the bow of either a VLCC or another LNG carrier. Based on the computed results, the collision resistance indices (CRI), which in the present study are defined as a function of the ratio of the structural energy dissipation capability to the initial kinetic energy loss, are calculated for the object Ship for various collision scenarios. Some important insights useful for preventing collision damage of the spherical LNG cargo tanks of the Ship are also discussed.