Journal articles: 'Dynamic FEM analysis of ship structures'

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Liang, Bing Nan, Hong Liang Yu, and Yu Chao Song. "Analysis of Damping Performance for Cabin Deck Covered with Floating Floor Coverings." Advanced Materials Research 610-613 (December 2012): 2566–70. http://dx.doi.org/10.4028/www.scientific.net/amr.610-613.2566.

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Floating floor coverings are widely applied in ship structures. With regard to the laminated composite shells made up of floating floor coverings and cabin deck and based on ANSYS system, a dynamics analysis on structures of three different kinds of floating floors is performed using FEM built upon laminated shell elements. The influence of rockwool board in terms of thickness, density and elastic modulus on structure dynamic characteristics is discussed. The performances of vibration control of three different floating floor structures are compared. The FEM performs well in analyzing and calculating the vibration control characteristics of structures, the results of which offer certain reference to the design and research on cabin deck covered with floating floor coverings.

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Domnisoru, Leonard, Ionica Rubanenco, and Mihaela Amoraritei. "Structural Safety Assessment of a 1100 TEU Container Ship, Based on a Enhanced Long Term Fatigue Analysis." Advanced Materials Research 1036 (October 2014): 935–40. http://dx.doi.org/10.4028/www.scientific.net/amr.1036.935.

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This paper is focused on an enhanced integrated method for structural safety assessment of maritime ships under extreme random wave loads. In this study is considered an 1100 TEU container test ship, with speed range 0 to 18 knots. The most comprehensive criteria for ships structural safety evaluation over the whole exploitation life is based on the long term ship structures analysis, that includes: stress hot-spots evaluation by 3D/1D-FEM hull models, computation of short term ship dynamic response induced by irregular waves, long term fatigue structure assessment. The analysis is enhanced by taking into account the ships speed influence on hydroelastic response. The study includes a comparative analysis on two scenarios for the correlation between the ships speed and waves intensity. The standard constant ship speed scenario and CENTEC scenario, with total speed loss at extreme waves condition, are considered. Instead of 20 years ship exploitation life estimated by classification societies rules from the long term structural safety criteria, the enhanced method has predicted more restrictive values of 14.4-15.7 years. The numerical analyses are based on own software and user subroutines. The study made possible to have a more realistic approach of ships structural strength assessment, for elastic and faster ships as container carriers, in compare to the standard one based only on naval rules, delivering a method with higher confidence in the designed structural safety.

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Singh, Janhavi, and Shilpa Pal. "Analysis of Blended Concrete Cubes under Impact loading using ANSYS." IOP Conference Series: Earth and Environmental Science 1084, no. 1 (October 1, 2022): 012067. http://dx.doi.org/10.1088/1755-1315/1084/1/012067.

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Abstract Blended concretes, with the partial replacement of the cement with secondary cementitious material like fly ash, rice husk ash, GGBS (Ground Granulated Blast Slag), silica fume etc. are gaining a wide range of applications in civil engineering nowadays. The behaviour of concrete structures has been studied by many researchers under different types of loads like impact load, wind load, earthquake load etc. Impact loading analysis has applications like ship impact resistance design for marine structures, impact-resistant structural design against military and terrorist attacks etc. This study aims to perform a FEM analysis of blended concrete cubes under impact load. Deformation and stress response has been obtained from the velocity impact simulations in ANSYS Explicit dynamics module. Parametric analysis has been done by changing the height of the impactor, shape of the impactor, boundary conditions and partial replacement of cement in the blended concrete with different supplementary cementitious material. It is observed that the strength of the blended concrete cube decreases with an increase in height of the impact.

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Park, Jeong Hee, and Duck Young Yoon. "A Proposal of Mode Polynomials for Efficient Use of Component Mode Synthesis and Methodology to Simplify the Calculation of the Connecting Beams." Journal of Marine Science and Engineering 9, no. 1 (December 26, 2020): 20. http://dx.doi.org/10.3390/jmse9010020.

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Analytical method using Rayleigh–Ritz method has not been widely used recently due to intensive use of finite element analysis (FEA). However as long as suitable mode functions together with component mode synthesis (CMS) can be provided, Rayleigh–Ritz method is still useful for the vibration analysis of many local structures in a ship such as tanks and supports for an equipment. In this study, polynomials which combines a simple and a fixed support have been proposed for the satisfaction of boundary conditions at a junction. Higher order polynomials have been generated using those suggested by Bhat. Since higher order polynomials used only satisfy geometrical boundary conditions, two ways are tried. One neglects moment continuity and the other satisfies moment continuity by sum of mode polynomials. Numerical analysis have been performed for typical shapes, which can generate easily more complicated structures. Comparison with FEA result shows good agreements enough to be used for practical purpose. Frequently dynamic behavior of one specific subcomponent is more concerned. In this case suitable way to estimate dynamic and static coupling of subcomponents connected to this specific subcomponent should be provided, which is not easy task. Elimination of generalized coordinates for subcomponents by mode by mode satisfaction of boundary conditions has been proposed. These results are still very useful for initial guidance.

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Norwood, M. N., and R. S. Dow. "Dynamic analysis of ship structures." Ships and Offshore Structures 8, no. 3-4 (June 2013): 270–88. http://dx.doi.org/10.1080/17445302.2012.755285.

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Rao, T. V. S. R. Appa, Nagesh R. Iyer, J. Rajasankar, and G. S. Palani. "Dynamic Response Analysis of Ship Hull Structures." Marine Technology and SNAME News 37, no. 03 (July 1, 2000): 117–28. http://dx.doi.org/10.5957/mt1.2000.37.3.117.

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Finite-element modeling and use of appropriate analytical techniques play a significant role in producing a reliable and economic design for ship hull structures subjected to dynamic loading. The paper presents investigations carried out for the dynamic response analysis of ship hull structures using the finite-element method. A simple and efficient interactive graphical preprocessing technique based on the "keynode" concept and assembly-line procedure is used to develop the finite-element model of the hull structure. The technique makes use of the body plan of a ship hull to build the finite-element model through an interactive session. Stiffened plate/shell finite elements suitable to model the hull structure are formulated and used to model the structure. The finite elements take into account arbitrary placement of stiffeners in an element without increasing the number of degrees-of-freedom of the element. A three-dimensional finite-element model and a procedure based on the Bubnov-Galerkin residual approach are employed to evaluate the effects of interaction between the ship hull and water. Mode superposition technique is used to conduct the dynamic response analysis. The efficiency of the finite elements and the procedures is demonstrated through dynamic analysis of a submerged cantilever plate and a barge when both are subjected to sinusoidal forces. The dynamic responses exhibit expected behavior of the structure and a comparison with the results available in the literature indicate superior performance of the finite element and methodologies developed. Thus, the finite-element models and the procedures are found to be efficient and hence suitable for the dynamic analysis of similar structures.

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Cheung, Kwok Fai, Ludwig H. Seidl, and Suqin Wang. "Analysis of SWATH Ship Structures." Marine Technology and SNAME News 35, no. 02 (April 1, 1998): 85–97. http://dx.doi.org/10.5957/mt1.1998.35.2.85.

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Three methods of analysis of the primary structure of SWATH ships are examined. The quasistatic, rigid-dynamic and hydroelastic approaches are applied to analyze the structure of a detailed SWATH design. Deflections and stresses are calculated after each method and compared. The convergence of the hydroelastic approach with respect to the number of modes is also investigated. Although a relatively small ship is considered in this comparative study, hydroelastic effects are shown to be significant in areas of greater flexibility.

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Iatan, George Ciprian, Elisabeta Burlacu, and Leonard Dmnişoru. "Non-linear FEM analysis for ship panels under thermal loads." Analele Universităţii "Dunărea de Jos" din Galaţi. Fascicula XI, Construcţii navale/ Annals of "Dunărea de Jos" of Galati, Fascicle XI, Shipbuilding 43 (December 15, 2020): 95–102. http://dx.doi.org/10.35219/annugalshipbuilding.2020.43.12.

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During the past decade, welding remained the main technological procedure for joining steel components in shipbuilding industry. Though it has great benefits, welding is an aggressive process that introduces high stress and strains in the joined materials, causing distortion. Finite element method is an important instrument for predicting how structures are behaving under thermal loads. This paper is focused on studying the behaviour of small thickness ship panels, under straightening treatment, by performing thermal-structural-elastic-plastic analysis in Femap/NX Nastran. The proposed panel is tested under three different thermal loadings in order to study stresses and residual distortion.

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Zhao, Yao, Wei Xin Zhou, Wei Bin Liu, Wen Yi, and Chang Gao. "Strength Calculation of Foam Core Sandwich Composite Ship by FEM." Materials Science Forum 813 (March 2015): 102–8. http://dx.doi.org/10.4028/www.scientific.net/msf.813.102.

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The foam core sandwich composite ship is a new kind ship using special materials. The advantages include easy molding, short construction period and so on. However, due to the specialty of the material property as well as the complexity of structures, there are element applicability and calculation efficiency problems when conducting FEA (Finite Element Analysis) calculations of the whole ship. Based on experiment and simulation result, a sandwich shell element is found which is equivalent to the solid element of beam and plate. An efficient and practical way is developed using this equivalent shell element to calculate a catamaran including the analysis of the structure responses in different working conditions. This methodology has a great reference value when conducting computer simulation calculation of foam core sandwich composite ships and marine structures.

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Li, Jie, Li Li Hu, Li Qin, Jun Liu, Rui Ping Tao, and Xi Ning Yu. "Dynamic Analysis of Piezoelectric Smart Structures." Advanced Materials Research 295-297 (July 2011): 1353–56. http://dx.doi.org/10.4028/www.scientific.net/amr.295-297.1353.

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In order to solve the active vibration control of piezoelectric smart structures, focus problems on the structural analysis of the dynamic characteristics. To piezoelectric smart structure for the research object, finite element modal analysis, solving the natural frequency and response characteristics. Firstly, analyzed the problems of structural eigenvalues and eigenvectors problems, then prepared dynamic response analysis program of FEM based on MATLAB, and complete the theoretical model calculations. At the same time, using ANSYS software to simulate and analyze, theresults show that, ANSYS simulation result is consistent with the theoretical value, so as to study the piezoelectric active vibration control of smart structures and lay a good foundation.

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Qiu, Liu Chao. "Dynamic Rupture Analysis of Concrete Structures by FEM-DEM Method." Advanced Materials Research 904 (March 2014): 241–45. http://dx.doi.org/10.4028/www.scientific.net/amr.904.241.

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A FEM-DEM approach was applied to investigate progressive rupture of concrete structures due to dynamic load including earthquakes. In the proposed method, the finite element method (FEM) designed for modelling stressed and deformed solids has been combined with the motion tracking capability of discrete element method (DEM). A fracture model combining single and smeared crack model is used in our simulation. The FEM-DEM method was used to simulate both the intact concrete behavior and the development of fractures in the indirect tensile test. The simulation results identify the failure mechanisms and validate the nature of tensile crack initiation and propagation in concrete disk. In particular, a comprehensive study on the seismic rupture of the Koyna dam during earthquakes is performed using the proposed method. It is shown that the proposed method can predicate the formation and propagation of cracks in concrete dam due to earthquakes.

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P. Tamayo, Jorge L., Armando M. Awruch, and Inácio B. Morsch. "DYNAMIC ANALYSIS OF REINFORCED CONCRETE STRUCTURES." Revista Cientifica TECNIA 22, no. 1 (April 4, 2017): 33. http://dx.doi.org/10.21754/tecnia.v22i1.88.

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ABSTRACTThe objective of this work is to provide a reliable numerical model using the finite element method (FEM) for the dynamic analysis of reinforced concrete (RC) structures. For this purpose, a computer program based on a strain-rate sensitive elasto-plastic theory is developed using 3D brick finite elements. The implicit Newmark scheme with predictor and corrector phases is used for time integration of the nonlinear system of equations. In addition, the steel reinforcement is considered to be smeared and perfectly adhered to concrete and represented by membrane finite elements. Two benchmark examples are analyzed with the present numerical model and results are compared with those obtained by other authors. The present numerical model is able to reproduce the path failure, collapse loads and failure mechanism within an acceptable level of accuracy. Keywords.-Reinforced concrete (RC) structures, Finite element method (FEM). RESUMENEl objetivo de este trabajo es presentar un modelo numérico confiable usando el método de los elementos finitos (MEF) para el análisis dinámico de estructuras de concreto reforzado. Con este propósito, un programa de cómputo basado en la teoría de elasto-plasticidad con sensibilidad a la velocidad de deformación es desarrollado usando elementos finitos tridimensionales. El procedimiento de Newmark es adoptado para la integración en el tiempo del sistema no linear de ecuaciones. Además, se supone que el acero de refuerzo está perfectamente distribuido e adherido al concreto, siendo representado por elementos finitos de membrana. Dos ejemplos son solucionados con el presente modelo numérico y los resultados obtenidos son comparados con los resultados de otros autores. Para todos los casos, la trayectoria de falla, la carga de colapso y el mecanismo de falla son reproducidos con suficiente precisión. Palabras clave.- Estructuras de concreto reforzado, Método de los elementos finitos (MEF).

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Žmindák, Milan, Josef Soukup, Lenka Rychlíková, and Jan Skočilas. "Finite Element Transient Dynamic Analysis of Laminated Composite Plates." Applied Mechanics and Materials 732 (February 2015): 357–64. http://dx.doi.org/10.4028/www.scientific.net/amm.732.357.

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In recent years, the requirements on the plane and space structures have been growing. The essential aim is to minimize weight and increase the strength and carrying capacity of these structures. One of the possible solutions is application of the layered structure composed from the composite materials. These materials represent the most effective utilization of potential possibilities of mass and energy savings not only from material point of view, but also with respect to structure usage. The article presents the Finite element method (FEM) solution of the displacement, velocity and acceleration distributions in the composite plates. The plate is unidirectional composite consisting of carbon fibers embedded in the epoxy matrix. FEM software ANSYS 11.0 has been used for analysis.

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Estêvão, João M. C., and Ana S. Carreira. "USING THE NEW FIBRE CONTACT ELEMENT METHOD FOR DYNAMIC STRUCTURAL ANALYSIS." Engineering Structures and Technologies 7, no. 1 (December 15, 2015): 24–38. http://dx.doi.org/10.3846/2029882x.2015.1087346.

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In literature, there are many methods proposed for structural analysis based on discrete element formulations, mainly for nonlinear problems. One of these new methods is the Fibre Contact Element Method (FCEM). Many of these methods have been used for structural dynamic analysis problems. However, there are some questions about their precision in capturing the dynamic elastic response of structures when comparing to methods based on continuous models, like the well known Finite Element Method (FEM). For this reason, the results obtained with FCEM were extensively compared with FEM results and with laboratorial tests, to better understand the performance of this new method in capturing the elastic dynamic response of structures. Results indicate that this kind of discrete methods are able to determine the vibration modes of a structure with equal or better precision level than the obtained with FEM. FCEM was also used to capture the dynamic response of a reinforced concrete frame with infill walls, as a way to show the method capabilities in reproducing the dynamic behaviour of structures that have an almost continuous mass distribution.

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Du, Wen Feng, Fu Dong Yu, and Zhi Yong Zhou. "Dynamic Stability Analysis of K8 Single-Layer Latticed Shell Structures Suffered from Earthquakes." Applied Mechanics and Materials 94-96 (September 2011): 52–56. http://dx.doi.org/10.4028/www.scientific.net/amm.94-96.52.

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Aiming at the dynamic stability of the K8 single-layer latticed shell structures, it was carried out the dynamic stability analysis based on the finite element method(FEM) in this paper. The dynamic responses of the structure are calculated using the FEM and the B-R rule is applied to determine the dynamic instability critical loads. Results show that the dynamic instability is prone to take place in the K8 single-layer latticed shell structures under the severe seismic load and the dynamic instability critical seismic wave peak value is about 0.7g. The location of instability starts from the intersection between the third circular members and the radial members, then it spreads abroad until the structure collapses.

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Vega Sáenz, Adán, Carlos Plazaola, Ilka Banfield, Sherif Rashed, and Hidekazu Murakawa. "Analysis and prediction of welding distortion in complex structures using elastic finite element method." Ciencia y tecnología de buques 6, no. 11 (July 21, 2012): 35. http://dx.doi.org/10.25043/19098642.67.

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The Elastic Finite Element Method based on the inherent strain theory is used to predict the welding distortion of ship structures. In addition, a method to predict welding distortion of complex structures by using elastic FEM is presented. To evaluate the effectiveness of the proposed method, a typical case of a ship's structure is examined and the resulting welding distortion is compared to that obtained by using thermal elastic-plastic finite element method.

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Sviličić, Šimun, and Smiljko Rudan. "Modelling Manoeuvrability in the Context of Ship Collision Analysis Using Non-Linear FEM." Journal of Marine Science and Engineering 11, no. 3 (February 25, 2023): 497. http://dx.doi.org/10.3390/jmse11030497.

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Ship collisions are rare events that may have a significant impact on the safety of people, ships, and other marine structures, as well as on the environment. Because of this, they are extensively studied but events that just precede collision are often overlooked. To rationally assess collision risks and consequences, a ship’s trajectory, and consequently the velocity and collision angle, should be known. One way to achieve this is through accurate modelling of ship manoeuvrability in collision analysis using non-linear FEM (NFEM). The Abkowitz manoeuvring model is implemented in the LS-Dyna software code and is therefore coupled with FEM calculations. Hydrodynamic forces are calculated in each time step of the LS-Dyna calculation and added to the FE model continuously through calculation. The accuracy of the calculations depends on the choice of and values of hydrodynamic derivatives from the Abkowitz model. Abkowitz’s model derives hydrodynamic forces in the Taylor expansion series to provide hydrodynamic derivatives. The application of the procedure is sensitive on higher-order Taylor series members. This article reviews different sets of hydrodynamic derivatives available for the KVLCC2 ship. Each of them is incorporated into the LS-Dyna NFEM solver by a user-made Fortran subroutine, with standard Zigzag and turning manoeuvres simulated and results compared with the experimental tests. As a result, the optimal selection of hydrodynamic derivatives is determined, laying a foundation for assessing the risk of ship collision due to different ship manoeuvres prior to the collision itself.

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Presura, Adrian, Ionel Chirica, and Elena Felicia Beznea. "Behavior Analysis of a Ship Structure Made out of Composite Materials." Advanced Materials Research 1143 (February 2017): 127–32. http://dx.doi.org/10.4028/www.scientific.net/amr.1143.127.

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. In this paper a parametric static and torsion analysis on a catamaran ship structure made out of composites materials is performed. The best solution for material selection is based on specific criteria for certain analysis. For dynamic analysis, the main criteria is to obtain the structure natural frequencies in a range, far from the resonance frequencies produced by the ship propulsion installation, wave loads etc. For static analysis the comparative criteria is to obtain the lowest weight of structure for the same strength. Also, buckling item is other criteria for comparative analysis. The comparative analysis is performed between rule based scantling structure and a FEM based structure for a composite material twin hull deck, in order to reduce the total hull weight. Material used for ship deck structure of the analyzed ship is e-glass polyester.

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Grządziela, Andrzej. "Ship Shock Modeling of Underwater Explosion." Solid State Phenomena 180 (November 2011): 288–96. http://dx.doi.org/10.4028/www.scientific.net/ssp.180.288.

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Ship shock tests have been conducted for shock qualification of hull integrity and proper operation systems and subsystems. The ship shock trial identifies design and construction and it also validates shock hardening criteria. The main problem is that ship shock trials are costly. Numerical modeling and simulation, using FEM, may provide information to look into the details of fluid model, dynamic characteristics of ship hull and its internal component. The ship shock modeling and simulation has been performed and the predicted results were compared with ship shock test data made into sea trials. The preliminary studies of shock analysis approach is presented and the important parameters are discussed.

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Grządziela, Andrzej, and Bogdan Szturomski. "Impact Modeling of Underwater Explosion." Solid State Phenomena 196 (February 2013): 51–61. http://dx.doi.org/10.4028/www.scientific.net/ssp.196.51.

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Ship shock tests have been conducted for shock qualification of hull integrity and proper operation systems and subsystems. The ship shock trial identifies design and construction and it also validates shock hardening criteria. The main problem is that ship shock trials are costly. Numerical modeling and simulation, using FEM, may provide information to look into the details of fluid model, dynamic characteristics of ship hull and its internal component. The ship shock modeling and simulation has been performed and the predicted results were compared with ship shock test data made into sea trials. The preliminary studies of shock analysis approach are presented and the important parameters are discussed

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Çağlar, N. Merve, and Erdal Şafak. "Application of Spectral Element Method for Dynamic Analysis of Plane Frame Structures." Earthquake Spectra 35, no. 3 (August 2019): 1213–33. http://dx.doi.org/10.1193/050818eqs115m.

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The paper presents a methodology to analyze plane frame structures using the Spectral Element Method (SEM) with and without considering Soil-Structure Interaction (SSI). The formulation of spectral element matrices based on higher-order element theories and the assemblage procedure of arbitrarily oriented members are outlined. It is shown that SEM gives more accurate results with much smaller computational cost, especially at high frequencies. Since the formulation is in the frequency domain, the frequency-dependent foundation impedance functions and SSI effects can easily be incorporated in the analysis. As an example, the dynamic response of a plane frame structure is calculated based on the Finite Element Method (FEM) and SEM. FEM and SEM results are compared at different frequency bands, and the effects of SSI on the dynamic response are discussed.

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ANGHEL, Viorel, Stefan SOROHAN, and Daniel HODOR. "FEM Applications of Catenary Type Structures." INCAS BULLETIN 14, no. 4 (December 2, 2022): 19–28. http://dx.doi.org/10.13111/2066-8201.2022.14.4.2.

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The paper deals with Finite Element Modeling of catenary type structures starting from practical problems related to a single cable segment in the case of an electric transmission line. Finite element models allow the analysis of the resulting deformed position and stress state for a given configuration obtained by using the geometric and physical data of a cable. Beam type linear/nonlinear finite element models which can take into account also the temperature variation and extra loading on the cable were developed. Another application of this type of models is for the case of form finding of aerial refueling cable subjected to dynamic pressure. The results were obtained by the commercial finite element software ANSYS.

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Kruszka, Leopold, Yu S. Vorobiov, and N. Yu Ovcharova. "FEM Analysis of Cylindrical Structural Elements under Local Shock Loading." Applied Mechanics and Materials 566 (June 2014): 499–504. http://dx.doi.org/10.4028/www.scientific.net/amm.566.499.

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High rate deformations of structures cylindrical elements are considered 3D formulation. Elastic-plastic finite deformations and dynamic properties of material take into account. The problem become geometrically and physically nonlinear and finite element method is used. The numerical analyses of dynamics stress-strain state of real structures elements is executed.

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Pruška, Jan. "EVALUATION OF UNDERGROUND STRUCTURES SUBJECTED TO SEISMIC LOADS." Acta Polytechnica CTU Proceedings 23 (July 30, 2019): 38–43. http://dx.doi.org/10.14311/app.2019.23.0038.

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The paper is focused on the evaluation of the effect of earthquakes on underground structures. Free-field analysis is one solution of this task common mainly in engineering tunnelling practice, but it has some rather simplified aspects (e.g. equivalent shear strain is constant). Pseudostatic finite element calculation combines free-field analysis and the advantages of a FEM model. Dynamic effects are introduced in the form of displacements prescribed along the vertical boundaries of the FEM model in a usually static manner. This approach also implies constant material parameters for the geological profile in the horizontal direction, an arbitrary geometry of excavation, soil structure interaction and description of share waves as a time-dependent 1D analysis of the so called free-field column. Moreover, there is shown an example comparing pseudo-static FEM analysis with an analytical method. Finally, the advantages of the pseudo-static FEM method are presented.

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Shin, Yung S., Booki Kim, and Alexander J. Fyfe. "Stress Combination for Fatigue Analysis of Ship Structures." Journal of Offshore Mechanics and Arctic Engineering 127, no. 2 (December 22, 2004): 175–81. http://dx.doi.org/10.1115/1.1924399.

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A methodology for calculating the correlation factors to combine the long-term dynamic stress components of ship structure from various loads in seas is presented. The proposed methodology is valid for a stationary ergodic narrow-banded Gaussian process. The total combined stress in short-term sea states is expressed by linear summation of the component stresses with the corresponding combination factors. This expression is proven to be mathematically exact when applied to a single random sea. The long-term total stress is similarly expressed by linear summation of component stresses with appropriate combination factors. The stress components considered here are due to wave-induced vertical bending moment, wave-induced horizontal bending moment, external wave pressure, and internal tank pressure. For application, the stress combination factors are calculated for longitudinal stiffeners in midship cargo and ballast tanks of a crude oil tanker. It is found that the combination factors strongly depend on wave heading and period in the short-term sea states. It is also found that the combination factors are not sensitive to the selected probability of exceedance level of the stress in the long-term sense.

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Kim, Sang Jin, and Jung Min Sohn. "The Effect of Dynamic Fracture Strain on the Structural Response of Ships in Collisions." Journal of Marine Science and Engineering 10, no. 11 (November 6, 2022): 1674. http://dx.doi.org/10.3390/jmse10111674.

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As ship collisions and grounding accidents lead to human injury and damage to the environment and property, more accurate predictions of structural damage to ships under impact loads are needed. Currently, to determine structural behaviors, finite element analysis (FEA) is frequently adopted. However, it is recommended to pay attention to material properties in FEA because structural damage is sensitive to material properties such as yield strength, fracture strain, etc. While the strain rate (impact speed) is automatically considered for dynamic yield stress using the Cowper–Symonds equation or other methods, the pre-defined fracture strain is generally used as the dynamic fracture strain (DFS), which is not dependent on strain rate during the simulation. This assigned value of fracture strain may affect the extent of damage and structural response. In this study, the effect of the DFS on the structural damage from collisions was investigated to determine the relationship between the DFS and damage. Empirical formulas based on predictions of damage by various events were developed as a function of the DFS and initial impact speed. The results of this study explained the effect of the DFS on the structural damage and determined the upper and lower bounds of damage by collisions.

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Kahsin, Maciej. "Numerical Modelling of Structures with Uncertainties." Polish Maritime Research 24, s1 (April 25, 2017): 125–32. http://dx.doi.org/10.1515/pomr-2017-0030.

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Abstract The nature of environmental interactions, as well as large dimensions and complex structure of marine offshore objects, make designing, building and operation of these objects a great challenge. This is the reason why a vast majority of investment cases of this type include structural analysis, performed using scaled laboratory models and complemented by extended computer simulations. The present paper focuses on FEM modelling of the offshore wind turbine supporting structure. Then problem is studied using the modal analysis, sensitivity analysis, as well as the design of experiment (DOE) and response surface model (RSM) methods. The results of modal analysis based simulations were used for assessing the quality of the FEM model against the data measured during the experimental modal analysis of the scaled laboratory model for different support conditions. The sensitivity analysis, in turn, has provided opportunities for assessing the effect of individual FEM model parameters on the dynamic response of the examined supporting structure. The DOE and RSM methods allowed to determine the effect of model parameter changes on the supporting structure response.

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Iegupov, Konstantin, Gennady Meltsov, Vyacheslav Iegupov, and Denys Bezushko. "Dynamic Calculation of the Pile Supported Wharf." ACADEMIC JOURNAL Series: Industrial Machine Building, Civil Engineering 2, no. 51 (October 12, 2018): 37–44. http://dx.doi.org/10.26906/znp.2018.51.1289.

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The article deals with the issues of designing and operating marine pile supported wharf in the seismically hazard areas considering various superstructures and overload equipment influence. Analysis of hydraulic structures seismic resistance erected in seismic regions of Ukraine shows that the actual seismic load on buildings significantly exceeds the estimated loads that are determined by the normative documents before 2006. Design of hydraulic structures should be done considering berths of reloading complexes, with proper scientific support. Berth construction calculationsof the ship repair yard No. 2 of the «Ilichevsk Ship Repair Plan» are given.

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Zorzal, Caroline Belisário, Christianne de Lyra Nogueira, and Hernani Mota de Lima. "Blast-induced ground vibrations: a dynamic analysis by FEM." Research, Society and Development 11, no. 13 (October 5, 2022): e205111335421. http://dx.doi.org/10.33448/rsd-v11i13.35421.

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The peak particle velocities (PPV) are fundamental for understanding and managing the levels of blast-induced ground vibrations and their effects on adjacent structures. Given that numerical analysis of seismic vibrations has been demonstrated to be a method that can significantly contribute to predicting PPV, this study adopts a numerical approach using the finite element method (FEM) to assess blasting-induced ground vibration in rock masses. A dynamic module of the stress-strain analysis based on the FEM displacement formulation is developed in ANLOG software to estimate the variations of displacement, velocity, strain, and stress induced by blasting. The dynamic modulus implemented is verified using two verification examples. After, ANLOG is used in an application example to estimate seismic vibrations induced by blasting and to define the attenuation law for a limestone quarry near an urbanized area in Spain. The effect of Rayleigh damping coefficients (α and β) on the PPV levels estimated by ANLOG was investigated, and the most appropriate numerical attenuation law is then obtained. The numerical analysis presents satisfactory results for elastic-wave propagation induced by blasting and the peak particle velocity values obtained shows good agreement with field and the numerical results available in the specialized literature. The results indicate that ANLOG can perform personalized analysis of rock mass under blast-induced dynamic stress taking into consideration the geological and geomechanical characteristics particular to each medium as well as the blast parameters.

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Chung, Nguyen Thai, Hoang Xuan Luong, and Nguyen Thi Thanh Xuan. "Dynamic stability analysis of laminated composite plates with piezoelectric layers." Vietnam Journal of Mechanics 36, no. 2 (June 10, 2014): 95–107. http://dx.doi.org/10.15625/0866-7136/36/2/3467.

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Research on the stability to determine the critical value of structures is a complex issue but of real significance. Piezoelectric composite plate is one of the structures which have the ability to control the mechanical behaviors under loads. One of the prominent capabilities of this structure is the ability to control its vibration and stability. Using the finite element method (FEM) and construction calculation program in Matlab, the authors analyzed the elastic stability of piezoelectric composite plates under dynamic in-plane loads, taking into account damping properties of the structure. Critical loads and other factors affecting the stability of the plate are investigated.

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Kopuz, Şadi, Y. Samim Ünlüsoy, and Mehmet Çalişkan. "Integrated FEM/BEM approach to the dynamic and acoustic analysis of plate structures." Engineering Analysis with Boundary Elements 17, no. 4 (June 1996): 269–77. http://dx.doi.org/10.1016/s0955-7997(96)00026-4.

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Yam, L. H., Li Cheng, Z. Wei, and Y. J. Yan. "Damage Detection of Composite Structures Using Dynamic Analysis." Key Engineering Materials 295-296 (October 2005): 33–38. http://dx.doi.org/10.4028/www.scientific.net/kem.295-296.33.

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A study on the use of modal parameter analysis for damage detection of structures made of composites is conducted. The damage-induced variations of modal parameters are investigated both numerically and experimentally. An appropriate finite element model is proposed to analyze the dynamic characteristics of different types of structures made of composites, such as honeycomb sandwich plates and multi-layer composite plates, with internal cracks and delamination. The numerical results are in good agreement with experimental results available in the literature. Natural frequencies, modal displacements, strains and energy are analyzed for the determination of damage severity and location. Vibration measurements are carried out using piezoelectric patch actuators and sensors for comparison and verification of the FEM model proposed in this study. Energy spectrum for wavelet packets decomposition of structural dynamic responses is used to highlight the features of damaged samples. The mechanism of mode-dependent energy dissipation of composite plates due to delamination is revealed for the first time. Experimental results clearly show the dependence of changes of modal parameters on damage size and location. The results obtained in this study show that the measured modal damping change combined with the computed modal strain energy distribution can be used to determine the location of delamination in composite structures. Both numerical and experimental findings in this study are significant to the establishment of guideline for size and location identification of damage in composite structures.

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Fang, Ren, Qin Zhaohong, Zhang Zhong, Liu Zhenhao, Yuan Kai, and Wei Long. "Modeling and dynamic environment analysis technology for spacecraft." International Journal of Computational Materials Science and Engineering 07, no. 01n02 (June 2018): 1850007. http://dx.doi.org/10.1142/s2047684118500070.

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Spacecraft sustains complex and severe vibrations and acoustic environments during flight. Predicting the resulting structures, including numerical predictions of fluctuating pressure, updating models and random vibration and acoustic analysis, plays an important role during the design, manufacture and ground testing of spacecraft. In this paper, Monotony Integrative Large Eddy Simulation (MILES) is introduced to predict the fluctuating pressure of the fairing. The exact flow structures of the fairing wall surface under different Mach numbers are obtained, then a spacecraft model is constructed using the finite element method (FEM). According to the modal test data, the model is updated by the penalty method. On this basis, the random vibration and acoustic responses of the fairing and satellite are analyzed by different methods. The simulated results agree well with the experimental ones, which shows the validity of the modeling and dynamic environment analysis technology. This information can better support test planning, defining test conditions and designing optimal structures.

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Yuan, Song Mei, Zhong Fei Zhan, and Yao Li. "Optimum Design of Machine Tool Structures Based on BP Neural Network and Genetic Algorithm." Advanced Materials Research 655-657 (January 2013): 1291–95. http://dx.doi.org/10.4028/www.scientific.net/amr.655-657.1291.

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In order to estimate and optimize the static and dynamic characteristics of machine tool, the full parameterized FEM model of it is established and studied in the paper. After the FEM analysis of bed, this paper takes a machine bed as example, presents a method of combination of BP Neural-Network(NN) and Genetic-Algorithm(GA) to optimize dynamic characteristics and realizes the structural optimization of the bed. It proved that this method takes less time, and more precision compared to traditional method.

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Zhang, Lei, Jin-Ting Wang, Yan-Jie Xu, Chun-Hui He, and Chu-Han Zhang. "A Procedure for 3D Seismic Simulation from Rupture to Structures by Coupling SEM and FEM." Bulletin of the Seismological Society of America 110, no. 3 (May 5, 2020): 1134–48. http://dx.doi.org/10.1785/0120190289.

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ABSTRACT This article aims at numerically simulating the 3D seismic wave propagation from rupture to structures. A two-step method coupling the spectral element method (SEM) and the finite-element method (FEM) is proposed based on the domain reduction method to simultaneously simulate the seismic wave propagation in large-scale regions and analyze the dynamic behavior of structures in local sites. First, the concept of the proposed two-step method is illustrated. In the first step, the seismic wave propagation of the entire area, involving the source, propagation media, and local region of interest, is simulated using the SEM. In the second step, the dynamic analysis of structure-foundation system with local geological and topographical conditions is implemented using the FEM in a fine mesh based on the results in the first step. Subsequently, the FEM grid size is evaluated to match the SEM results, and the proposed SEM–FEM procedure is verified using both point-source and finite-fault model in a layered flat model. Finally, two analysis examples are presented using the proposed procedure. The analysis results show that the proposed SEM–FEM procedure can well consider the effects of local geological and topographical conditions on synthesized ground motions and can be applied to the rupture-to-structure simulations in earthquake engineering.

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Yang, Jie, De-you Zhao, and Ming Hong. "An efficient method for non-stationary random vibration analysis of beams." Journal of Vibration and Control 17, no. 13 (February 24, 2011): 2015–22. http://dx.doi.org/10.1177/1077546310395961.

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An efficient method is presented to investigate the non-stationary random vibration response of structures. This method has the advantage of the accuracy of theoretical method in dealing with random loads and the versatility of the finite element method (FEM) in dealing with structures. In this paper, the Euler beam is adopted in the derivation of the governing equation. The uncoupled approach of the frequency-dependent system matrices is presented for solving the motion equation of forced vibration. The time-variance random dynamic response of the beam is analyzed by the precise integral method, meanwhile, the pseudo-excitation is applied to transform the non-stationary random excitation into deterministic pseudo one to simplify the solution of the dynamic equation. Solutions calculated by the FEM with different time step and theoretical analysis are also obtained for comparison. Numerical examples demonstrate the accuracy and high efficiency of the proposed method.

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Коршунов, В. А., Р. С. Мудрик, Д. А. Пономарев, and А. А. Родионов. "Strength analysis of ship shafts made of polymer composite materials." MORSKIE INTELLEKTUAL`NYE TEHNOLOGII)</msg>, no. 4(54) (December 2, 2021): 31–37. http://dx.doi.org/10.37220/mit.2021.54.4.064.

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В работе отмечена актуальность применения ПКМ для перспективных проектов судов при отсутствии инженерных методов расчета параметров НДС таких изделий. Сделана попытка исследования возможностей аналитического и численного подходов для анализа прочностных и жесткостных характеристик судовых валов из ПКМ. Разработана расчетная модель вала в виде цилиндрической оболочки, составленной из пакета нескольких монослоев, каждый из которых сформирован из армирующего волокна и связующей матрицы. Представлены аналитические зависимости для вычисления обобщенных характеристик жесткости оболочки вала и параметров НДС как оболочки в целом, так и ее монослоев. Эти зависимости использованы для расчетного исследования параметров прочности промежуточного вала из ПКМ для танкера химовоза. В процессе исследования варьировалась ориентация и количество монослоев в пакете. Верификация полученных результатов выполнена с помощью расчетных моделей МКЭ. В результате установлено, что аналитические зависимости позволяют получить достоверные результаты параметров НДС композитного тела вала, которые можно уверенно использовать в расчетном проектировании конструкций из ПКМ для анализа плоского напряженно-деформированного состояния оболочки вала. he relevance of the use of PCM for the first projects of ships in the absence of engineering methods for calculating the parameters of the strength of such products is noted. In structural mechanics, there are methods for calculating the strength of multicomponent anisotropic materials, but they are difficult to adapt to engineering methods of verification calculation and design. The article attempts to study the possibilities of analytical and FEM approaches for analyzing the strength and stiffness of ship shafts made of PCM. A model of the shaft consisting of a package of several monolayers. Analytical dependences are presented for calculating the characteristics of the stiffness of the shaft shell. These dependences are used for the computational study of the strength parameters of the intermediate shaft made of PCM for tanker. Verification of the obtained results was carried out using of the FEM. As a result, it is established that the analytical dependences allow us to obtain reliable results of the stress-strain parameters of the composite shaft housing, which can be used in the computational design of PCM structures to analyze the flat stress-strain state of the shaft shell.

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Shao, Ren Ping, Xin Na Huang, Pu Rong Jia, Wan Lin Guo, and Kaoru Hirota. "Dynamic Analysis and Three-Dimensional Finite Element Simulation of Cracked Gear." Key Engineering Materials 353-358 (September 2007): 1072–77. http://dx.doi.org/10.4028/www.scientific.net/kem.353-358.1072.

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A method of damage detection and fault diagnosis for gears is presented based on the theory of elastomeric dynamics according to the theory of cracked beam. It takes an advantage of accurate fault diagnosis of gear body using the change of dynamic features and has some advantages for dynamic design of gear systems.The dynamics characteristics, i.e., natural frequency, vibration shape,dynamic response and so on, due to crack of gear tooth are studied, and the gear dynamics characteristics caused by the position and size of crack are deeply investigated by comparison with FEM. The theoretical analysis results are contrasted with numerical simulation results and shows good agreement with the result by FEM. The proposed method can be used to detect damage and diagnose fault for gear structures and also can be applied to designing dynamic characteristics for gear systems.

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Jia, Junbo, and Jonas W. Ringsberg. "Numerical and Experimental Investigation of Dynamics of Vehicle/Ship-Deck Interactions." Marine Technology and SNAME News 45, no. 01 (January 1, 2008): 28–41. http://dx.doi.org/10.5957/mt1.2008.45.1.28.

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The paper presents numerical modeling and analysis of vehicle/ship-deck interactions and a review of similar models and approaches in the literature. The physical modeling of vehicles is discussed together with the modeling of supporting structures/ship decks, and the interactions between vehicles and supporting structures. Some engineering applications are studied, for example, the dynamic structural behavior of vehicle/ship-deck systems, vehicle vibrations, damping effects of vehicles on structural systems, dynamic interactions between tires and deck surfaces, and vehicle securing on decks during ship motions. In addition, results from modal testing of unloaded and vehicle-loaded lightweight deck systems in a ship and the tire-deck friction under dynamic loading are reported. The results are used for validation and verification of models. Finally, vehicle transportation using RO/RO ships and lashing-free vehicle concept ideas are studied and discussed.

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Duris, Rastislav. "A Determination of Material Properties of Flexible Structures Using EMA and FEM Analysis." Applied Mechanics and Materials 693 (December 2014): 293–98. http://dx.doi.org/10.4028/www.scientific.net/amm.693.293.

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Dynamic behavior of mechanical structures results from complex interactions between applied forces and the stiffness properties of the structure. Currently, many problems of structural dynamic analysis are solved using Finite Element Method (FEM). However, in recent years, the implementation of the Fast Fourier Transform (FFT) in low cost computer-based signal analyzers has provided a powerful tool for acquisition and analysis of vibration data. This article discusses combination of two approaches to structural dynamics testing; the experimental part which is referred to as Experimental Modal Analysis (EMA), respectively the analytical part, which is realized by Finite Element Analysis (FEA). Main goal of the paper is calculation of material properties from experimentally determined modal frequencies.

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Al-Helwani, Amjad, Mohamad Khir Abdul-wahed, and Mohanad Talal Alfach. "Dynamic behavior assessment of public buildings in Syria using non-linear time-history analysis and ambient noise measurements: a case study." Asian Journal of Civil Engineering 22, no. 4 (January 9, 2021): 637–48. http://dx.doi.org/10.1007/s42107-020-00337-w.

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AbstractThis study evaluates the dynamic behavior and performance of vital reinforced concrete (RC) public building [Ministry of Higher Education (MHE)] designed in compliance with the old Syrian (non-seismic) building code. The real non-linear dynamic behavior of the MHE building has been checked by detailed dynamic numerical analyses (finite elements method—FEM) validated by a series of ambient noise measurements carried out on-site. The modeling approach for the thorough 3D dynamic analyses of the (RC) MHE building has been developed to be able to investigate the actual non-linear dynamic performance of widespread range of RC structures, providing the opportunity to set up a reliable detailed methodology to assess the real dynamic performance of the old vital structures designed according to the old Syrian (non-seismic) building code from the new seismic requirements perspective. The results of the frequency analyses, the nonlinear time history, and the experimental measurements have shown an excellent agreement. The study showed that the modeling approach by the FEM is reliable for predicting the actual dynamic behavior of RC structures, but it is very sensitive to the modeling assumptions. Furthermore, the dynamic performance analyses have revealed unsymmetrical behavior of the east–west wings about the Y-axis which could be attributed to the inefficient seismic rehabilitation executed in 2001.

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Цуканова, Екатерина, and Ekaterina Tsukanova. "Analysis of forced vibrations of frameworks by finite element method using dynamic finite element." Bulletin of Bryansk state technical university 2015, no. 2 (June 30, 2015): 93–103. http://dx.doi.org/10.12737/22911.

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The analysis of forced vibrations of frameworks using finite element method is considered. The dynamic finite element, the base functions of which represent exact dynamic shapes of structural elements, is used for system discretization. The assessment of errors as a result of classic FEM application is given. The efficiency of application of dynamic finite element for analysis of forced vibrations and dynamic stress-deformed state of structures is shown.

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Xie, Hai Bo, Zheng Jiang Liu, Yang Song, and Shi Bo Zhou. "Research and Analysis on Damage of Marine Ship Structures by Composite Materials Based on FEM Numerical Simulation." Key Engineering Materials 852 (July 2020): 129–38. http://dx.doi.org/10.4028/www.scientific.net/kem.852.129.

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In view of the particularity of marine foam sandwich composite structure, this paper establishes an equivalent parameter conversion system based on the classical sandwich structure design idea, and forms an equivalent simulation method to determine the initial stiffness, initial failure load and ultimate failure load of the structure. The simulation discriminant method makes the SHELL91 shell unit available for the marine foam sandwich composite structure. The bending test of the basic structure of marine foam sandwich composite beams and plates is described in detail. The equivalent simulation method is verified. The initial stiffness, initial failure load and ultimate failure load of the equivalent simulation are in good agreement with the experimental results. The paper finds through the finite element numerical simulation that the research results are consistent with the reality and have strong practicability and popularization. The paper preliminarily believes that this method can be applied to the simulation calculation of large foam sandwich composite ships and marine structures. The calculation amount is greatly reduced based on ensuring the accuracy, and the calculation work such as strength criterion and stiffness check of the overall structure has Strongly convincing.

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Liu, Qiang. "Research on Dynamic Characteristics and Response of Double-Tower Connected Structures." Applied Mechanics and Materials 578-579 (July 2014): 877–81. http://dx.doi.org/10.4028/www.scientific.net/amm.578-579.877.

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The dynamic analysis method and theory of double-tower connected structures is discussed in this paper .Then modal analysis、static and dynamic time-history analysis is researched with the FEM software ANSYS. Through the structure of monomer and comparative study of the structure in different locations, the basic rules of dynamic characteristics and the rules of layout corridor can be achieved. In addition, by symmetric and asymmetric conjoined comparative study, the basic choose rules of structure type can also be achieved.

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Orlowitz, Esben, and Anders Brandt. "Operational Modal Analysis for Dynamic Characterization of a Ro-Lo Ship." Journal of Ship Research 58, no. 04 (December 1, 2014): 216–24. http://dx.doi.org/10.5957/jsr.2014.58.4.216.

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The dynamic characteristics of ship structures are becoming more important as the flexibility of modern ships increases, for example, to predict reliable design life. This requires an accurate dynamic model of the structure, which, because of complex vibration environment and complex boundary conditions, can only be validated by measurements. In the present paper the use of operational modal analysis (OMA) for dynamic characterization of a ship structure based on experimental data, from a full-scale measurement of a 210-m long Ro-Lo ship during sea trial, is presented. The measurements contain three different data sets obtained under different operating conditions of the ship: 10 knots cruising speed, 18 knots cruising speed, and at anchor. Natural frequencies, modal damping ratios, and mode shapes have been successfully estimated for the first 10 global modes. Damping ratios for the current ship were found within the range 0.9%–1.9% and natural frequencies were found to range from 0.8 to 4.1 Hz for the first 10 global modes of the ship at design speed (18 knots). The three different operating conditions showed, in addition, a speed dependency of the natural frequencies and damping ratios. The natural frequencies were found to be lower for the 18-knots condition compared with the two other conditions, most significantly for the vertical bending modes. Also, for the vertical bending modes, the damping ratios increased by 28%–288% when the speed increased from 10 to 18 knots. Other modes were not found to have the same strong speed dependency.

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Tamayo, Jorge Luis Palomino, Armando Miguel Awruch, and Inácio Benvegnu Morsch. "Numerical modeling of reinforced concrete structures: static and dynamic analysis." Rem: Revista Escola de Minas 66, no. 4 (December 2013): 425–30. http://dx.doi.org/10.1590/s0370-44672013000400004.

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A numerical model using the Finite Element Method (FEM) for the nonlinear static and dynamic analysis of reinforced concrete (RC) beams, plates and shells is presented in this work. For this purpose, computer programs based on plasticity theory and with crack monitoring capabilities are developed. The static analysis of RC shells up to failure load is carried out using 9-node degenerated shell finite elements while 20-node brick finite elements are used for dynamic applications. The elasto-plastic constitutive law for concrete is coupled with a strain-rate sensitive model in order to take into account high loading rate effect when transient loading is intended. The implicit Newmark scheme with predictor and corrector phases is used for time integration of the nonlinear system of equations. In both cases, the steel reinforcement is considered to be smeared and represented by membrane finite elements. Various benchmark examples are solved with the present numerical model and comparisons with other published data are performed. For all examples, the path failure, collapse loads and failure mechanism is reproduced with great accuracy.

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Zhu, J.-Y. "Analysis of dynamic behaviour of low vibration track under wheel load drop by a finite element method algorithm." Proceedings of the Institution of Mechanical Engineers, Part F: Journal of Rail and Rapid Transit 222, no. 2 (March 1, 2008): 217–23. http://dx.doi.org/10.1243/09544097jrrt165.

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According to finite-element method (FEM) analytical solution (based on penalty algorithm) and the control equations of wheel—rail contact (developed from point-to-surface contact elements), the vibration responses were simulated for the two alternative railway track structures impacted by a falling wheel-set. The dynamic behaviour of low vibration track (LVT) is investigated based on this numerical method, which is verified by the field experiments. The results show that, when compared with the conventional short sleeper buried track (SSBT), the LVT is more beneficial for the reduction of track structure vibration levels — thanks to its properly matched stiffness under rail and block. Furthermore, it is demonstrated that the proposed wheel-load-drop FEM numerical procedure and field experiment can effectively and economically study the dynamic properties of track structures.

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Kan, Ziyun, Haijun Peng, Biaoshong Chen, and Wanxie Zhong. "Nonlinear dynamic and deployment analysis of clustered tensegrity structures using a positional formulation FEM." Composite Structures 187 (March 2018): 241–58. http://dx.doi.org/10.1016/j.compstruct.2017.12.050.

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Rudan, Smiljko, Stipe Tomašević, and Ivo Senjanović. "Fatigue Analysis of Structural Details of an Oceangoing LPG Ship." Key Engineering Materials 348-349 (September 2007): 573–76. http://dx.doi.org/10.4028/www.scientific.net/kem.348-349.573.

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Structural details of ship structures are prone to fatigue damage mainly due to high-cycle wave load and low-cycle cargo loading/unloading. Full stochastic fatigue analysis of selected structural details on an oceangoing 6500 cbm LPG ship is presented. A critical Y-joint of longitudinal bulkhead and bilobe tank shell as well as double-bottom girder details are selected due to different reasons. The eccentricity of the Y-joint, leads to significant stress concentration. Saddle supports of gas tanks cause stress concentration in ship double bottom due to weight and dynamic loads. Wave load on ship structure is calculated using linear strip theory for ship in ballast condition and full ship. Wave load is transferred to ship finite element model and notch structural stresses are determined using finite element analysis. Stochastic fatigue analysis is then performed, taking into account sailing route and other ship operational parameters. Finally, fatigue damage summation is done and results are discussed.

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Chirica, Ionel, and Elena Felicia Beznea. "Structural Solutions for Ship Hull Plates Strengthening, under Blast Loads." Key Engineering Materials 601 (March 2014): 76–79. http://dx.doi.org/10.4028/www.scientific.net/kem.601.76.

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The paper presents selected results of a study concerning the protective capacity of ship hull plates, made out of layered composite plates. A scenario to evaluate the behaviour of the ship structure plate under blast loading is presented. The nonlinear analysis on a 3-D FEM model by using composite elements was performed. The methodology for the blast pressure charging and the mechanism of the blast wave in free air are given. The space pressure variation is determined by using Friedlander exponential decay equation. According to the methods used in this paper an individual pressure-time history to each element based on its distance from the blast is assigned. The dynamic response of the composite plate is shown.

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Journal articles on the topic 'Dynamic FEM analysis of ship structures'

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