Arvid Naess - Academia.edu (original) (raw)
Papers by Arvid Naess
Journal of Engineering Mechanics-asce, Aug 1, 2008
... (2007). Clustering effects on the extreme response statistics for dynamical systems. Proc.,... more ... (2007). Clustering effects on the extreme response statistics for dynamical systems. Proc., 5th Int. ... (2007). An importance sampling procedure for estimating failure probabilities of nonlinear dynamic systems subjected to random noise. Int. J. Non-Linear Mech., 42, 848863. ...
Ocean Engineering, Nov 1, 2007
Stochastic Dynamics of Marine Structures
Frontiers in Mechanical Engineering, Jul 4, 2022
Cambridge University Press eBooks, Feb 5, 2013
Journal of Sea Research, Apr 1, 2023
Cambridge University Press eBooks, Feb 5, 2013
Cambridge University Press eBooks, Feb 5, 2013
Introduction The first step in planning response analysis is whether the analysis can be accompli... more Introduction The first step in planning response analysis is whether the analysis can be accomplished as a static one or whether a dynamic model must be used. Dynamic analyses are generally necessary in connection with transient loads; otherwise, the results may be significantly conservative or nonconservative. For load processes consisting of several harmonic components, the main criterion is whether the load process contains energy in the range of eigenfrequencies of the system. Figure 14.1 shows an overview of the largest eigenperiod (natural period) of vibration or motion of offshore structures, as well as the relevant range of periods of dynamic loads associated with waves. Solution of Equations of Motion General The equations of motion for a linear structural system (Section 4.10) may be solved in the time or frequency domain. The choice of formulation especially depends on: The nature of the loading; i.e., whether it is steady state or transient (which often involves response in a wide frequency band). Frequency dependence of the dynamic properties (mass, damping, Nonlinear features of the loading or dynamic properties. In Chapter 2, solutions of the equation of motion for SDOF systems with different load conditions are described. If the solution method either in time or frequency domain is formulated for the coupled system of equations in Eq. (14.1), the method is denoted as direct.
The Second International Offshore and Polar Engineering Conference, 1992
International Journal of Mechanical Sciences, Jul 1, 2018
Cambridge University Press eBooks, Feb 5, 2013
Cambridge University Press eBooks, Feb 5, 2013
Cambridge University Press eBooks, Feb 5, 2013
Introduction This chapter deals with vibrations of structures that can be represented as a single... more Introduction This chapter deals with vibrations of structures that can be represented as a single degree-of-freedom (SDOF) system. This means that the oscillatory response can be completely described by one displacement variable. This may seem like a gross oversimplification for structures of engineering interest that leads to a theory of little practical significance. However, the theory of vibrations for systems of an SDOF is crucial for understanding the vibration response of more complex structures. Frequently, it is also the case that one may investigate the vibration response characteristics of apparently complex structures by directly applying the theory of vibrations of SDOF systems. This is demonstrated in Chapter 3 on multi-degrees-of-freedom (MDOF) structures. The word “vibration” used in this chapter should be interpreted as meaning oscillatory response in a fairly general sense, e.g., as applied to marine structures. Harmonic Oscillator – Free Vibrations Free vibrations or oscillations occur when there are no external forces imposed on the structure, e.g., after an initial displacement and release. Two different situations are discussed: translational oscillations and rotational oscillations. Motions of Marine Structures Because the main focus of this book is the motion response of marine structures, it is expedient to define the terms commonly used to describe the rigid-body motions of floating structures. This is most easily done by referring to Fig. 2.1. For a shiplike structure, it is common practice to place the x -axis along the beam of the ship (for the body-fixed coordinate system), and call the corresponding translational motion for surge.
Cambridge University Press eBooks, Feb 5, 2013
Journal of Sound and Vibration, Jul 1, 2017
Probabilistic Engineering Mechanics, Apr 1, 2022
The paper discusses the problem, of linearization for the purpose of simplified calculation of lo... more The paper discusses the problem, of linearization for the purpose of simplified calculation of long-term fatigue damage in offshore structures. Specific linearization procedures are proposed that may be better suited to deal with the problem of fatigue life calculation than the standard mean square stochastic linearization (MSSL). These are based on minimizing higher order moments of the linearization error, and it is indicated how the optimal order is linked to the street exponent of the S-N curve. It is shown by specific example studies that the proposed method may lead to substantial improvement over MSSL in estimating fatigue damage.
Engineering mechanics, 1996
Journal of Engineering Mechanics-asce, Aug 1, 2008
... (2007). Clustering effects on the extreme response statistics for dynamical systems. Proc.,... more ... (2007). Clustering effects on the extreme response statistics for dynamical systems. Proc., 5th Int. ... (2007). An importance sampling procedure for estimating failure probabilities of nonlinear dynamic systems subjected to random noise. Int. J. Non-Linear Mech., 42, 848863. ...
Ocean Engineering, Nov 1, 2007
Stochastic Dynamics of Marine Structures
Frontiers in Mechanical Engineering, Jul 4, 2022
Cambridge University Press eBooks, Feb 5, 2013
Journal of Sea Research, Apr 1, 2023
Cambridge University Press eBooks, Feb 5, 2013
Cambridge University Press eBooks, Feb 5, 2013
Introduction The first step in planning response analysis is whether the analysis can be accompli... more Introduction The first step in planning response analysis is whether the analysis can be accomplished as a static one or whether a dynamic model must be used. Dynamic analyses are generally necessary in connection with transient loads; otherwise, the results may be significantly conservative or nonconservative. For load processes consisting of several harmonic components, the main criterion is whether the load process contains energy in the range of eigenfrequencies of the system. Figure 14.1 shows an overview of the largest eigenperiod (natural period) of vibration or motion of offshore structures, as well as the relevant range of periods of dynamic loads associated with waves. Solution of Equations of Motion General The equations of motion for a linear structural system (Section 4.10) may be solved in the time or frequency domain. The choice of formulation especially depends on: The nature of the loading; i.e., whether it is steady state or transient (which often involves response in a wide frequency band). Frequency dependence of the dynamic properties (mass, damping, Nonlinear features of the loading or dynamic properties. In Chapter 2, solutions of the equation of motion for SDOF systems with different load conditions are described. If the solution method either in time or frequency domain is formulated for the coupled system of equations in Eq. (14.1), the method is denoted as direct.
The Second International Offshore and Polar Engineering Conference, 1992
International Journal of Mechanical Sciences, Jul 1, 2018
Cambridge University Press eBooks, Feb 5, 2013
Cambridge University Press eBooks, Feb 5, 2013
Cambridge University Press eBooks, Feb 5, 2013
Introduction This chapter deals with vibrations of structures that can be represented as a single... more Introduction This chapter deals with vibrations of structures that can be represented as a single degree-of-freedom (SDOF) system. This means that the oscillatory response can be completely described by one displacement variable. This may seem like a gross oversimplification for structures of engineering interest that leads to a theory of little practical significance. However, the theory of vibrations for systems of an SDOF is crucial for understanding the vibration response of more complex structures. Frequently, it is also the case that one may investigate the vibration response characteristics of apparently complex structures by directly applying the theory of vibrations of SDOF systems. This is demonstrated in Chapter 3 on multi-degrees-of-freedom (MDOF) structures. The word “vibration” used in this chapter should be interpreted as meaning oscillatory response in a fairly general sense, e.g., as applied to marine structures. Harmonic Oscillator – Free Vibrations Free vibrations or oscillations occur when there are no external forces imposed on the structure, e.g., after an initial displacement and release. Two different situations are discussed: translational oscillations and rotational oscillations. Motions of Marine Structures Because the main focus of this book is the motion response of marine structures, it is expedient to define the terms commonly used to describe the rigid-body motions of floating structures. This is most easily done by referring to Fig. 2.1. For a shiplike structure, it is common practice to place the x -axis along the beam of the ship (for the body-fixed coordinate system), and call the corresponding translational motion for surge.
Cambridge University Press eBooks, Feb 5, 2013
Journal of Sound and Vibration, Jul 1, 2017
Probabilistic Engineering Mechanics, Apr 1, 2022
The paper discusses the problem, of linearization for the purpose of simplified calculation of lo... more The paper discusses the problem, of linearization for the purpose of simplified calculation of long-term fatigue damage in offshore structures. Specific linearization procedures are proposed that may be better suited to deal with the problem of fatigue life calculation than the standard mean square stochastic linearization (MSSL). These are based on minimizing higher order moments of the linearization error, and it is indicated how the optimal order is linked to the street exponent of the S-N curve. It is shown by specific example studies that the proposed method may lead to substantial improvement over MSSL in estimating fatigue damage.
Engineering mechanics, 1996