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Abstrak :
The fixed jacket is still the most common offshore structure used for drilling and oil production. The structure consists of tubular members interconnected to form a three-dimensional space frame, which can be categorized into a column structure. The structure usually has four to eight legs that are battered to achieve stability against axial compressive loads and toppling due to wave loads. The configuration of a typical member on the jacket structure has significant influence on buckling and fatigue strength. Horizontal and diagonal braces play an important role in resisting the axial compression and wave load on the global structure. This paper discusses the effect of symmetrical and asymmetrical configuration shapes in buckling and fatigue strength analysis on two types of fixed jacket offshore platforms. The axial compressive and lateral (wave) loads were considered and applied to both structures. The material and dimensions of the two structures were assumed to be constant and homogenous. Crack extension and corrosion were not considered. To assess the buckling and fatigue strength of these structures, due to the symmetrical and asymmetrical configuration shape, the finite element method (FEM) was adopted. Buckling analysis was performed on these structures by taking two-dimensional planes into consideration to obtain the critical buckling load for the local plane; fatigue life analysis was then calculated to produce the fatigue life of those structures. The result obtained by FEM was compared with the analytical solution for the critical buckling load. The stress-strain curve was also applied to show the difference between symmetrical and asymmetrical shapes. For fatigue life analysis, the procedure of the response amplitude operator was applied.

Abstrak :
The fixed jacket is still the most common offshore structure used for drilling and oil production. The structure consists of tubular members interconnected to form a three-dimensional space frame, which can be categorized into a column structure. The structure usually has four to eight legs that are battered to achieve stability against axial compressive loads and toppling due to wave loads. The configuration of a typical member on the jacket structure has significant influence on buckling and fatigue strength. Horizontal and diagonal braces play an important role in resisting the axial compression and wave load on the global structure. This paper discusses the effect of symmetrical and asymmetrical configuration shapes in buckling and fatigue strength analysis on two types of fixed jacket offshore platforms. The axial compressive and lateral (wave) loads were considered and applied to both structures. The material and dimensions of the two structures were assumed to be constant and homogenous. Crack extension and corrosion were not considered. To assess the buckling and fatigue strength of these structures, due to the symmetrical and asymmetrical configuration shape, the finite element method (FEM) was adopted. Buckling analysis was performed on these structures by taking two-dimensional planes into consideration to obtain the critical buckling load for the local plane; fatigue life analysis was then calculated to produce the fatigue life of those structures. The result obtained by FEM was compared with the analytical solution for the critical buckling load. The stress-strain curve was also applied to show the difference between symmetrical and asymmetrical shapes. For fatigue life analysis, the procedure of the response amplitude operator was applied.

Abstrak :
This book presents a theoretical approach that allows the analysis of structures with magnetorheological and electrorheological layers, and shows, with the help of examples, how the mechanical behaviour of thin-walled laminated structures can be influenced. It consists of six chapters: Chapter 1 presents a brief overview of derivation approaches for theories of thin-walled structures, modelling of composites and modelling of laminated and sandwich structures. Chapter 2 describes the equivalent single layer model for thin laminated cylindrical shells, including the special cases of plates and beams. In addition to the classical mechanical properties, it also considers the electrorheological and magnetorheological properties. Chapter 3 presents the elastic buckling of laminated beams, plates, and cylindrical shells, discussing various problems, such as the influence of the boundary conditions, external loading and magnetic fields. It also suggests different approximations for asymptotic methods. Chapter 4 focuses on the free vibrations of elastic laminated beams, plates and cylindrical shells, investigating the influence of the boundary conditions and other factors. Chapter 5 presents the latest results concerning vibration of laminated structures composed of smart materials and discusses in detail the influence of electric and magnetic fields on smart structures. These results provide insights into the optimal design of these structures. Lastly, Chapter 6 features a short appendix presenting asymptotic estimates and series.

Abstrak :
This book addresses the static and dynamic analysis of linear elastic size-dependent structures based on the modified couple stress theory. It focuses on establishing the governing equations of the size-dependent structures, deriving the associated finite element models, and implementing those models using the R programming language. The implemented functions are employed to develop a special R package (equivalent to a MATLAB toolbox) called microfiniteR for this book. In each chapter, the governing equations are formulated using the variational method, and the behaviour of the structures is examined on the basis of their load-deformation characteristics (in the case of static analyses) and by evaluating their eigenvalues (in the case of dynamics and buckling problems). The first chapter introduces readers to the R programming language, beginning with the resources needed to make use of the language and ending with a list of recommended texts. The remaining chapters cover the requisite linear elastic theory and highlight the implemented R functions. Each chapter concludes with a brief summary and relevant references.