Modal analysis superelement 1 superelement 2 transfer back to physical coordinate of substructure 1 transfer back to physical coordinate of substructure 2 use pass step 2 pass step 1 expansion pass step 3 transfer back to physical coordinate of. Advanced methods of structural analysis civil engineering. This reduces the required computation time and also allows the solution of. Divided into 12 chapters, matrix methods for advanced structural analysis begins with an introduction to the analysis of structures fundamental concepts and basic steps of structural analysis, primary structural members and their modeling, brief historical overview of methods of static analysis, programming principles. Hpcc methodologies for structural design and analysis. There are instances, such as the use of substructuring for the analysis of large structures, in which it might be advantageous to reduce the number of nodal coordinates. This technique involves breaking the system into parts, analyzing the parts, and then reassembling the total system using selected degrees of freedom from the parts. For this method, the structure is divided into sub. The size of the model and the number of the uncertain parameters are much smaller than those of the global. The term mode can refer to all kind of structural shape vectors. Matrix structural analysis the stiffness method matrix structural analyses solve practical problems of trusses, beams, and frames.
Substructuring introduction this tutorial was completed using ansys 7. Displacement stiffness method express local member force displacement relationships in terms of unknown member displacements. The substructuring methods are promising to be combined with the nonlinear analysis, vibration control, and parallel computation as well. A substructuring based design analysis procedure is presented for large smart structural system using the craigbampton method. A read is counted each time someone views a publication summary such as the title, abstract, and list of authors, clicks on a figure, or views or downloads the fulltext. The following theorem shows the equivalence of an entire class of decomposed problems to the underlying original problem. The book aims to help its readers master the numerous methods used in structural analysis by focusing on the principal concepts, as well as. The possible use of mode superposition in nonlinear analysis is quite natural, because mathematically only a change of basis to a computationally more effective system of equations is performed i, 31.
Summary of substructuring methods w static structukal analysis the method of substructuring for static structural analysis is based on subdividing the large structure into smaller parts which are analyzed separately to obtain relationships between forces and displacements at the part interfaces. This is known as a single degreeoffreedom sdof system as. In situations where we need to find the internal forces only in a few specific members of a truss, the method of sections is more. Application of the substructuring technique to the stress. Structure as a whole or any substructure must satisfy 1. Substructuring is a procedure that condenses a group of finite elements into one superelement. Only the substructures are repeatedly analyzed and the re analysis of the global structure is thereby avoided. Substructuring methods primarily serve to achieve reduction in computational. Substructuring method in structural health monitoring intechopen. The organization and bookkeeping routine are described for a basic frontal program which is suitable for frame analysis of large structures using a minimum of computer core capacity and auxiliary storage. An easily implemented static condensation method for structural sensitivity analysis.
An easily implemented static condensation method for. We have addressed the solution of such problems by a twofield hybrid method where the substructures are joined. Real time hybrid testing or real time substructuring is a hardwareintheloop approach for testing structural components of complex systems with realistic boundary conditions by cou pling. The substructuring method is preferable to cope with large scale structures. The motivations for employing substructuring in finite element modeling vary from reduction of computational time, modal synthesis using substructure modes, combining experimental and numerical modeling approaches, equitable sharing of resources in parallel computing environment, and treatment of globallocal nonlinearities.
Substructuring methods for finite element analysis springerlink. The device, called wavestar, is a bottom fixed structure, located in a shallow water environment at the danish northwest coast. The static condensation method has recently been modified for applications to dynamic problems. In the afternoon, you are to answer 60 questions, and structural analysis is about 10% of the test content or about 6 questions. Structural analysis iv chapter 5 structural dynamics 4 dr. Matrix structural analysis of substructures aiaa journal. This well established textbook includes numerous worked examples and problems and answers.
Asen 5007 introduction to finite element methods course. May 17, 2012 a finite element based substructuring procedure for design analysis of large smart structural systems 9 march 2009 smart materials and structures, vol. Substructuring is a technique in finite element analysis for solving mechanical engineering problems involving large structures which are too enormous for existing computer hardware and software to handle. Integrated matrix analysis of structures pp 239260 cite as. An improved method of substructure analysis sciencedirect. Dynamic substructuring ds is an engineering tool used to model and analyse the dynamics of mechanical systems by means of its components or substructures. Substructuring in linear and nonlinear analysis wiley online library. Improved componentmode representation for structural. Substructure synthesis methods and their application to structural. Substructuring requires the reduction of nodal coordinates to allow the independent analysis of portions of the structure substructuring. Structural diagnosis is conducted by means of the comparison of the response, strain, stress, and stiffness in healthy and unhealthy states, or the measurement data only in the damageexpected state without the baseline data. This is known as a single degreeoffreedom sdof system as there is only one possible. Construction of stiffness and flexibility for substructurebased.
A structural design decomposition method utilizing substructuring stephen j. A finite element based substructuring procedure for design. This book should be of interest to undergraduate students on structural analysis and design courses, forming part of degree courses on civil and structural engineering. Abstract pdf 2011 kb 1990 an iterative substructuring algorithm for equilibrium equations. A substructuring method for geometrically nonlinear structures. Construction of stiffness and flexibility for substructure. Structural modeling and analysis of a wave energy converter. The analysis is concentrated on a single float and its structural arm which connects the wec to a jackup structure. It is important to understand how the method works. Scotti nasa langley research center hampton, virginia abstract the present paper describes a new method of design decomposition for structural analysis and optimization.
Optimization and a users manual for program trussopt3, technical. The modalbased methods involve the coupling of substructure eigenanalysis results to arrive. The procedures for utilizing substructuring and static condensation in structural analysis are well known. We have addressed the solution of such problems by a. The smart structural system is distinctively characterized as an active substructure, modelled as a design problem, and a passive substructure, idealized as an analysis problem. Robust design in structural acoustics, substructuring. To find the optimal searching direction, sensitivity analysis is usually conducted to. Stiffness methods for systematic analysis of structures. Substructure based approach to finite element model. Advanced methods of structural analysis aims to help its readers navigate through the vast field of structural analysis. This paper deals with structural modeling and analysis of a wave energy converter.
Also, substructuring could help to save disk space and computing time. Improved componentmode representation for structural dynamic. Matrix methods for advanced structural analysis 1st edition. Introduction of structural analysis structural analysis. A structural design decomposition method utilizing. Analysis performed in appendix is serving as an essential foreknowledge needed for the substructuring and superelements approach to be implemented and applied. Structural analysis using a basic frontal method canadian. A multiple coupling algorithm for the stiffness method of structuralanalysis.
When the substructuring method is applied in model updating or damage identification, only one or more substructures are involved in an optimization procedure. Discussion focuses on a number of aspects including. A structural design decomposition method utilizing substructuring. Analysis of patch substructuring methods 397 elements, such a splitting is less natural, but other splittings could be used, as we will see later. In this cho ice played a principal role the conviction of obtaining a better approximation to the global stiffness of the system by using substructuring than using submodelling. The method of mode superposition has already been applied in nonlinear. Cms is a type of substructuring which performs a modal analysis of a structure based on independent modal analyses of its parts the synthesis involves making the components work together as a single structure by satisfying intercomponent compatibility and equilibrium constraints master dof are required only at interface nodes. Chapters 14, 15, 16 the stiffness method provides a very systematic way of analyzing determinate and indeterminate structures. A finite element based substructuring procedure for design analysis of large smart structural systems 9 march 2009 smart materials and structures, vol.
Pdf substructuring and dual methods in structural analysis. Module ii analysis of continuous beam and simple portals by kanis method, analysis of two pinned. Second, the substructuring methods allow for the analysis of local parts. This displacement method analysis automatically partitions the stiffness matrix of an idealized structure in a manner similar to substructuring. Stiffness methods for systematic analysis of structures ref. Apr 19, 2018 prebook pen drive and g drive at teacademy. Define analysis type solution analysis type new analysis substructuring antype,subst select substructuring analysis options it is necessary to define the substructuring analysis options select solution analysis type analysis options the following window will appear. Status and recent developments of substructuring techniques and their application to structural analysis and design are summarized. This book is written for students of universities and colleges pursuing civil or structural engineering programs, instructors of structural analysis, and engineers. Only the substructures are repeatedly analyzed and the reanalysis of the global structure is thereby avoided. Bce 306 structural analysis ii module i introduction to force and displacement methods of structural analysis, analysis of continuous beam and plane frame by slope deflection method and moment distribution method. Pdf on jan 1, 1997, daniel rixen and others published substructuring and dual methods in structural analysis find, read and cite all the research you need on researchgate.
Using the dynamic substructuring approach one is able to analyse the dynamic behaviour of substructures separately and to later on calculate the assembled dynamics using coupling procedures. Dynamic substructuring techniques can be classified in two categories depending on the underlying modes which are used 1. Daisy engineers manual, volumes 1 and 2, university of arizona, tucson 1970. Here, the given structure is divided into a set of subsystems, each component is. The first class consists of methods using fixed interface. Matrix force method also called as flexibility method. Benscotenthe partitioning of matrices in structural analysis. As for the main part of the thesis, first an overview of fem implementation in structural analysis is presented. Pdf a substructuring method for geometrically nonlinear. Crack identification in an offshore structural frame through. Divided into 12 chapters, matrix methods for advanced structural analysis begins with an introduction to the analysis of structures fundamental concepts and basic steps of structural analysis, primary structural members and their modeling, brief historical overview of methods. Pdf on jan 1, 1997, daniel rixen and others published substructuring and dual methods in structural analysis find, read and cite all the. In the inverse substructuring method, the experimental modal data of the.
Pdf analysis of frames by substructuring technique based on. An analysis method of large structure using matrix blocking journal of the korea institute for structural maintenance and inspection, vol. For simplicity of calculation and reduction of computational time and resources, a twodimensional plane frame instead of the actual threedimensional space frame structure was used in the numerical analysis. The stiffness method is currently the most common matrix structural analysis technique because it is amenable to computer programming. The book aims to help its readers master the numerous methods used in structural analysis by focusing on the principal concepts, as well as the advantages and disadvantages of each method.
This reduces the required computation time and also allows the solution of very large problems. The substructuring methods have proved to be accurate and efficient for the analysis of largescale structure, and they have been extensively. Printed in great bri an improved method of substructure analysis c. Robust design in structural acoustics, substructuring techniques and perturbation methods wilbert dijkhof june 19, 2003 1 introduction this is a part of the state of art report of the ph. Deshpande indian institute of technology, bombay 400 076, india received 20 august 1976 abstractubstructure method is an established way of overcoming the difficulty of large dimensionality in analysing structures. Method of sections the method of joints is good if we have to find the internal forces in all the truss members. Substructuring and superelements technique is introduced. Application of substructuring methods to the dynamic finite. Static condensation and substructuring springerlink. However, until recently there have been no general. Joining of complex substructures by the matrix force method. Caprani the most basic dynamic system is the massspring system. With substructuring methods, a global structure is divided into a number of independent substructures. Modeling stiffness, loads and displacement boundary conditions.
Evaluation of substructure reduction techniques with fixed. Investigation of substructuring principles in the finite. Substructuring techniquesstatus and projections sciencedirect. Class note for structural analysis 2 fall semester, 20 hae sung lee, professor dept. Fem discretization and the direct stiffness method 9 lectures.
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