Chopra, A.K. Dynamics of Structures – Theory and Applications to Earthquake Engineering. Prentice Hall, 2001
Chen, C. T. Linear System Theory and Design. Oxford University Press, 1999
Soong, T.T. Active Structural Control: Theory and Practice. Longman, 1990
Chapter 1 Review of Structural Dynamics
Chapter 2 Mathematical Description of Structural Systems
Chapter 3 State-space Realizations
Chapter 4 Introduction of Passive Energy Dissipation Systems
Chapter 5 Application of Passive Control
Chapter 6 Controllability and Observability
Chapter 7 State Feedback and State Estimators
Chapter 8 Application of Passive and Active Control
Chapter 9 Application of Semi-active and Hybrid Control
The document summarizes key concepts in the theory of structures including:
- Types of loads, reactions, and supports
- Statically determinate beams, frames, arches, and trusses
- Relationship between loads, shear forces, and bending moments
- Concepts of stability, determinacy, and methods of analysis for solving equilibrium and conditional equations
Examples are provided to demonstrate solving for reactions, internal forces, and conditional equations for various statically determinate structures. Factors affecting stability and determinacy are also discussed.
Este documento presenta los criterios de diseño para miembros estructurales de madera, incluyendo 1) fundamentos como pilotes de madera y cimentación continua, 2) diseño de columnas mediante el cálculo de dimensiones para resistir cargas, y 3) diseño de vigas considerando fuerzas cortantes, momento flector y rigidez. También describe el diseño de otros elementos como cerchas, entrepisos y techos. El objetivo es aplicar estos criterios al diseño de una vivienda unifamiliar de dos niveles.
This document provides an introduction to reinforced concrete, including its key components and purposes. Reinforced concrete is a composite material made of concrete, which resists compression well but has low tensile strength, and steel reinforcing bars, which resist tension well. Together they create an economical and strong structural material. The document outlines structural elements, design considerations for safety, reliability, and economy, and limit state design principles which ensure structures do not fail under expected loads. It also discusses factors that affect concrete durability and different failure modes in reinforced concrete depending on steel reinforcement ratios.
Shear walls are preferred in seismic regions because they are very effective at resisting lateral forces during earthquakes. Shear walls are vertical structural elements designed to transfer seismic forces throughout the height of the building. They provide large strength, high stiffness, and ductility. Shear wall buildings have performed much better during past earthquakes compared to reinforced concrete frame buildings. Some key advantages of shear walls include good earthquake resistance when designed properly, easy construction, reduced construction costs, and minimized damage to structural and non-structural elements during seismic events.
Roy Belton: Design manual for roads and bridges - loads for highway bridgesRoy Belton
This standard specifies the loading to be used for the design of highway bridges and associated structures through the attached revision of the Composite Version of BS 5400: Part 2. This revision to BS 5400: Part 2 also includes the clauses that relate to railway bridge live load.
This document discusses pushover analysis, which is an inelastic static analysis method used to evaluate seismic performance of structures. It begins by outlining the target performance levels dictated by codes, then provides an overview of current analysis methods and their limitations. Next, it describes the steps of a pushover analysis in detail, including defining member behavior, applying loads, specifying the load pattern, and incrementally forming plastic hinges. An example application to a 3-story frame structure is presented to demonstrate the process. The document concludes by emphasizing pushover analysis as a practical alternative to time history analysis for estimating seismic response.
Hibbeler, Russell C. Engineering mechanics: Statics. Pearson Prentice Hall, 2016
Chapter 1 Introduction and General Principles
Chapter 2 Equilibrium of a Particle
Chapter 3 Systems of Forces and Moments
Chapter 4 Equilibrium of a Rigid Body
Chapter 5 Analysis of a Structure
Chapter 6 Internal Forces and Moments
Chapter 7 Friction
Chapter 8 Center of Gravity and Centroid
Chapter 9 Moments of Inertia
Chapter 10 Virtual Work
Chapter 5: Axial Force, Shear, and Bending MomentMonark Sutariya
1. A beam can experience three internal forces at a section - axial force, shear, and bending moment. Even for planar beams, all three forces may develop.
2. There are three types of supports - roller/link, pin, and fixed. Roller/link supports resist one force, pin supports resist two forces, and fixed supports resist two forces and a moment.
3. Beams can experience different load types - concentrated, uniform distributed, and varying distributed loads. Methods are presented to calculate the shear, axial, and bending effects of these loads on beams.
The document summarizes key concepts in the theory of structures including:
- Types of loads, reactions, and supports
- Statically determinate beams, frames, arches, and trusses
- Relationship between loads, shear forces, and bending moments
- Concepts of stability, determinacy, and methods of analysis for solving equilibrium and conditional equations
Examples are provided to demonstrate solving for reactions, internal forces, and conditional equations for various statically determinate structures. Factors affecting stability and determinacy are also discussed.
Este documento presenta los criterios de diseño para miembros estructurales de madera, incluyendo 1) fundamentos como pilotes de madera y cimentación continua, 2) diseño de columnas mediante el cálculo de dimensiones para resistir cargas, y 3) diseño de vigas considerando fuerzas cortantes, momento flector y rigidez. También describe el diseño de otros elementos como cerchas, entrepisos y techos. El objetivo es aplicar estos criterios al diseño de una vivienda unifamiliar de dos niveles.
This document provides an introduction to reinforced concrete, including its key components and purposes. Reinforced concrete is a composite material made of concrete, which resists compression well but has low tensile strength, and steel reinforcing bars, which resist tension well. Together they create an economical and strong structural material. The document outlines structural elements, design considerations for safety, reliability, and economy, and limit state design principles which ensure structures do not fail under expected loads. It also discusses factors that affect concrete durability and different failure modes in reinforced concrete depending on steel reinforcement ratios.
Shear walls are preferred in seismic regions because they are very effective at resisting lateral forces during earthquakes. Shear walls are vertical structural elements designed to transfer seismic forces throughout the height of the building. They provide large strength, high stiffness, and ductility. Shear wall buildings have performed much better during past earthquakes compared to reinforced concrete frame buildings. Some key advantages of shear walls include good earthquake resistance when designed properly, easy construction, reduced construction costs, and minimized damage to structural and non-structural elements during seismic events.
Roy Belton: Design manual for roads and bridges - loads for highway bridgesRoy Belton
This standard specifies the loading to be used for the design of highway bridges and associated structures through the attached revision of the Composite Version of BS 5400: Part 2. This revision to BS 5400: Part 2 also includes the clauses that relate to railway bridge live load.
This document discusses pushover analysis, which is an inelastic static analysis method used to evaluate seismic performance of structures. It begins by outlining the target performance levels dictated by codes, then provides an overview of current analysis methods and their limitations. Next, it describes the steps of a pushover analysis in detail, including defining member behavior, applying loads, specifying the load pattern, and incrementally forming plastic hinges. An example application to a 3-story frame structure is presented to demonstrate the process. The document concludes by emphasizing pushover analysis as a practical alternative to time history analysis for estimating seismic response.
Hibbeler, Russell C. Engineering mechanics: Statics. Pearson Prentice Hall, 2016
Chapter 1 Introduction and General Principles
Chapter 2 Equilibrium of a Particle
Chapter 3 Systems of Forces and Moments
Chapter 4 Equilibrium of a Rigid Body
Chapter 5 Analysis of a Structure
Chapter 6 Internal Forces and Moments
Chapter 7 Friction
Chapter 8 Center of Gravity and Centroid
Chapter 9 Moments of Inertia
Chapter 10 Virtual Work
Chapter 5: Axial Force, Shear, and Bending MomentMonark Sutariya
1. A beam can experience three internal forces at a section - axial force, shear, and bending moment. Even for planar beams, all three forces may develop.
2. There are three types of supports - roller/link, pin, and fixed. Roller/link supports resist one force, pin supports resist two forces, and fixed supports resist two forces and a moment.
3. Beams can experience different load types - concentrated, uniform distributed, and varying distributed loads. Methods are presented to calculate the shear, axial, and bending effects of these loads on beams.
The document discusses the seismic design philosophy for buildings according to Indian seismic codes. It outlines three key parts: 1) The importance of seismic codes like IS 1893 and IS 4326 which provide guidance for earthquake-resistant design of different structure types. 2) The earthquake problems are divided into three cases of minor/frequent, moderate/occasional, and strong/rare shaking and how structures should perform. 3) The seismic design philosophy is based on a dual safety-level and serviceability-level approach to satisfy performance requirements under extreme and more regular earthquake events through ductile detailing of structural elements.
What is a single degree of freedom (SDOF) system ?
Hoe to write and solve the equations of motion?
How does damping affect the response?
#WikiCourses
https://wikicourses.wikispaces.com/Lect01+Single+Degree+of+Freedom+Systems
https://eau-esa.wikispaces.com/Topic+Single+Degree+of+Freedom+%28SDOF%29+Systems
Pushover is a static-nonlinear analysis method where a structure is subjected to gravity loading and a monotonic displacement-controlled lateral load pattern which continuously increases through elastic and inelastic behavior until an ultimate condition is reached. Lateral load may represent the range of base shear induced by earthquake loading, and its configuration may be proportional to the distribution of mass along building height, mode shapes, or another practical means.
The static pushover analysis is becoming a popular tool for seismic performance evaluation of existing and new structures. The expectation is that the pushover analysis will provide adequate information on seismic demands imposed by the design ground motion on the structural system and its components. The purpose of the paper is to summarize the basic concepts on which the pushover analysis can be based, assess the accuracy of pushover predictions, identify conditions under which the pushover will provide adequate information and, perhaps more importantly, identify cases in which the pushover predictions will be inadequate or even misleading.
The document discusses various topics related to earthquakes and seismic design including:
1. Plate tectonics theory explains how the lithosphere is broken into plates that move relative to each other, causing earthquakes along plate boundaries.
2. Earthquakes are measured on the Richter scale and can cause damage depending on factors like magnitude, distance from epicenter, and soil properties.
3. Seismic design codes aim to prevent collapse from major earthquakes through concepts like ductility, overstrength, and redundancy while allowing some damage from minor quakes.
4. Dynamic analysis methods like response spectrum and time history are used to design important structures, while the equivalent lateral force method is commonly used for other
Este documento presenta el cálculo estructural de una losa reticulada de concreto reforzado. Se describe el cálculo del peso propio de la losa, la determinación de las cargas vivas y la carga total. También incluye el cálculo del refuerzo requerido considerando los momentos flectores, cortantes y deflexiones. Finalmente, se verifica que la losa cumple con los requerimientos estructurales bajo las cargas de diseño.
Seismic analysis of multi storey reinforced concrete buildings frame”ankialok
The opinion that designing new buildings to be Earthquake resistant will cause substantial additional costs is still among the constructional professionals. In a country of moderate seismicity adequate seismic resistance of new buildings may be achieved at no or no significant additional cost however the expenditure needed to ensure adequate seismic resistance may depend strongly on the approach selected during the conceptual design phase and the relevant design method. Regarding the conceptual design phase early collaboration between the architect and civil engineering is crucial.
This document introduces base isolation as a seismic retrofitting technique. It defines base isolation as decoupling a structure's superstructure from its substructure using structural elements. The document discusses the principle of base isolation, which is to isolate the structure from ground movement. It compares base isolation to other retrofitting techniques, noting advantages such as reduced structural damage and maintenance costs. The document also outlines different base isolation systems using elastomeric bearings and sliding systems. Examples of base isolation projects and companies utilizing the technique are provided. The document suggests government initiatives and training to develop base isolation in India.
This document discusses solving the harmonic oscillator equation. It covers undamped and damped free vibrations as well as forced vibrations. For free vibrations, it examines the general solution and particular solutions. It also discusses topics like natural frequency, damping, and resonance. The document suggests modeling a vibrating beam as a harmonic oscillator and rewriting the equation as a first order system for numerical solving in Matlab. Lastly, it notes that the solution depends on ratios of m, c, and k rather than their individual values, which is important for solving the inverse problem.
Structural analysis is the process of determining how systems of forces and moments act upon structures such as buildings and bridges. Engineers use structural analysis to understand how external and internal forces are distributed throughout a structure, and how components will react to these forces. The goal of structural analysis is to ensure a structure can withstand expected forces without failing or experiencing excessive deformation.
Basic concepts in indian standard eq design codesdeua2004
The document provides guidelines for ductile detailing of reinforced concrete structures subjected to seismic forces according to Indian Standard IS 13920. Some key points:
1) Flexural members must have at least two longitudinal bars on the top and bottom throughout the member length. Minimum and maximum steel ratios are specified.
2) Anchorage lengths for beam bars in exterior joints must be development length plus 10 bar diameters beyond the inner face of the column.
3) Lap splices are only allowed in the central half of members and must be designed as tension splices with hoops of spacing ≤150mm over the entire splice length. No more than 50% of bars can be spliced at one section.
A comparative study of static and response spectrum analysis of a rc buildingTameem Samdanee
This presentation compares the results of static and response spectrum analysis of a 6-story reinforced concrete building. A 3D model of the building was created in ETABS and both static and dynamic analysis were performed. The natural periods and mode shapes were determined from the dynamic analysis. Storey displacements, drifts, and member forces from both analyses were compared. The dynamic analysis produced significantly higher results than the static analysis for storey displacements, drifts, shear forces, and bending moments. Specifically, dynamic displacements were over 2.5 times higher and bending moments were around 2 times higher than the static analysis results.
Prestressing is a technique where tension is applied to concrete before hardening to improve its performance. There are two main types - pre-tensioning and post-tensioning. Pre-tensioning involves tensioning steel tendons before casting concrete, while post-tensioning tensions tendons after casting. There are losses in prestress over time from factors like elastic shortening, shrinkage, creep, and steel relaxation. Proper materials and design are needed to account for these losses and ensure structures perform as intended.
Analysis and design of shear wall transfer beam structurephamtraoag
The document analyzes the stress behavior of shear walls and transfer beams due to their interaction. It presents a finite element analysis of a 22-story building model consisting of shear walls, transfer beams, and columns. Two analyses are performed: 1) With vertical loads only to verify the stress behavior matches previous research. 2) With both wind loads and vertical loads to observe stress behavior differences and obtain results for transfer beam design. Based on the second analysis, the transfer beam reinforcement is designed according to CIRIA Guide 2:1977 design standards.
Proposal defence slide on Analysis & Design of Multistoreylochan Shrestha
The document presents a structural analysis and comparison of design codes for a proposed 5.5 story reinforced concrete frame hospital building in Kathmandu, Nepal. It describes the building location, dimensions, structural system and objectives of analyzing the building using SAP2000 software and designing it according to Nepal's NBC and India's IS seismic codes. It also provides background on building analysis and design methods, factors of safety, load combinations specified in the two codes and their provisions for seismic analysis using the seismic coefficient and response spectrum methods.
The document provides an overview of prestressed concrete structures including:
- Definitions of prestressing where internal stresses counteract external loads.
- The key terminology used including tendons, anchorage, pretensioning vs post-tensioning.
- The materials used including cement, concrete, and steel types.
- The stages of loading and advantages of prestressing over reinforced concrete.
- Details of pretensioning and post-tensioning systems including equipment, processes, and differences between the two methods.
This document provides a summary of steel columns, including:
1. It defines steel columns and their key characteristics such as shape, load bearing capacity, and connections.
2. It classifies columns based on cross-sectional shape, loading type, reinforcement, and slenderness ratio.
3. It discusses effective length, slenderness ratio, column bases, and provides examples of calculating load capacity.
This document discusses the earthquake analysis of a 4-storey reinforced concrete building located in seismic zone IV using both manual calculations and STAAD Pro software. Static and dynamic analysis methods are used to calculate the base shear. For the static analysis, the base shear from manual calculations is 99.93 kN while from STAAD it is 87.88 kN. For the dynamic analysis, the manual base shear is 80.93 kN and from STAAD it is 83.89 kN. The results show that static manual calculations provide a more conservative base shear value compared to the other methods. Recommendations are made to further analyze irregular structures and consider nonlinear behavior.
The document discusses structural dynamics and analysis of multi-degree of freedom systems. It covers key concepts such as dynamic differential equations, natural frequencies, damping, modal analysis, and different analysis methods including direct integration and frequency-based approaches. Linear dynamics allows use of natural modes of vibration while nonlinear dynamics accounts for large motions and changing geometry. Damping dissipates energy through velocity-dependent forces. Analysis can be performed via direct time integration or modal superposition depending on the problem characteristics and dominant frequencies.
This is an Introductory material for those who want to understand the basic difference between linear and nonlinear analysis in the context of civil and structural engineering.
The document discusses the seismic design philosophy for buildings according to Indian seismic codes. It outlines three key parts: 1) The importance of seismic codes like IS 1893 and IS 4326 which provide guidance for earthquake-resistant design of different structure types. 2) The earthquake problems are divided into three cases of minor/frequent, moderate/occasional, and strong/rare shaking and how structures should perform. 3) The seismic design philosophy is based on a dual safety-level and serviceability-level approach to satisfy performance requirements under extreme and more regular earthquake events through ductile detailing of structural elements.
What is a single degree of freedom (SDOF) system ?
Hoe to write and solve the equations of motion?
How does damping affect the response?
#WikiCourses
https://wikicourses.wikispaces.com/Lect01+Single+Degree+of+Freedom+Systems
https://eau-esa.wikispaces.com/Topic+Single+Degree+of+Freedom+%28SDOF%29+Systems
Pushover is a static-nonlinear analysis method where a structure is subjected to gravity loading and a monotonic displacement-controlled lateral load pattern which continuously increases through elastic and inelastic behavior until an ultimate condition is reached. Lateral load may represent the range of base shear induced by earthquake loading, and its configuration may be proportional to the distribution of mass along building height, mode shapes, or another practical means.
The static pushover analysis is becoming a popular tool for seismic performance evaluation of existing and new structures. The expectation is that the pushover analysis will provide adequate information on seismic demands imposed by the design ground motion on the structural system and its components. The purpose of the paper is to summarize the basic concepts on which the pushover analysis can be based, assess the accuracy of pushover predictions, identify conditions under which the pushover will provide adequate information and, perhaps more importantly, identify cases in which the pushover predictions will be inadequate or even misleading.
The document discusses various topics related to earthquakes and seismic design including:
1. Plate tectonics theory explains how the lithosphere is broken into plates that move relative to each other, causing earthquakes along plate boundaries.
2. Earthquakes are measured on the Richter scale and can cause damage depending on factors like magnitude, distance from epicenter, and soil properties.
3. Seismic design codes aim to prevent collapse from major earthquakes through concepts like ductility, overstrength, and redundancy while allowing some damage from minor quakes.
4. Dynamic analysis methods like response spectrum and time history are used to design important structures, while the equivalent lateral force method is commonly used for other
Este documento presenta el cálculo estructural de una losa reticulada de concreto reforzado. Se describe el cálculo del peso propio de la losa, la determinación de las cargas vivas y la carga total. También incluye el cálculo del refuerzo requerido considerando los momentos flectores, cortantes y deflexiones. Finalmente, se verifica que la losa cumple con los requerimientos estructurales bajo las cargas de diseño.
Seismic analysis of multi storey reinforced concrete buildings frame”ankialok
The opinion that designing new buildings to be Earthquake resistant will cause substantial additional costs is still among the constructional professionals. In a country of moderate seismicity adequate seismic resistance of new buildings may be achieved at no or no significant additional cost however the expenditure needed to ensure adequate seismic resistance may depend strongly on the approach selected during the conceptual design phase and the relevant design method. Regarding the conceptual design phase early collaboration between the architect and civil engineering is crucial.
This document introduces base isolation as a seismic retrofitting technique. It defines base isolation as decoupling a structure's superstructure from its substructure using structural elements. The document discusses the principle of base isolation, which is to isolate the structure from ground movement. It compares base isolation to other retrofitting techniques, noting advantages such as reduced structural damage and maintenance costs. The document also outlines different base isolation systems using elastomeric bearings and sliding systems. Examples of base isolation projects and companies utilizing the technique are provided. The document suggests government initiatives and training to develop base isolation in India.
This document discusses solving the harmonic oscillator equation. It covers undamped and damped free vibrations as well as forced vibrations. For free vibrations, it examines the general solution and particular solutions. It also discusses topics like natural frequency, damping, and resonance. The document suggests modeling a vibrating beam as a harmonic oscillator and rewriting the equation as a first order system for numerical solving in Matlab. Lastly, it notes that the solution depends on ratios of m, c, and k rather than their individual values, which is important for solving the inverse problem.
Structural analysis is the process of determining how systems of forces and moments act upon structures such as buildings and bridges. Engineers use structural analysis to understand how external and internal forces are distributed throughout a structure, and how components will react to these forces. The goal of structural analysis is to ensure a structure can withstand expected forces without failing or experiencing excessive deformation.
Basic concepts in indian standard eq design codesdeua2004
The document provides guidelines for ductile detailing of reinforced concrete structures subjected to seismic forces according to Indian Standard IS 13920. Some key points:
1) Flexural members must have at least two longitudinal bars on the top and bottom throughout the member length. Minimum and maximum steel ratios are specified.
2) Anchorage lengths for beam bars in exterior joints must be development length plus 10 bar diameters beyond the inner face of the column.
3) Lap splices are only allowed in the central half of members and must be designed as tension splices with hoops of spacing ≤150mm over the entire splice length. No more than 50% of bars can be spliced at one section.
A comparative study of static and response spectrum analysis of a rc buildingTameem Samdanee
This presentation compares the results of static and response spectrum analysis of a 6-story reinforced concrete building. A 3D model of the building was created in ETABS and both static and dynamic analysis were performed. The natural periods and mode shapes were determined from the dynamic analysis. Storey displacements, drifts, and member forces from both analyses were compared. The dynamic analysis produced significantly higher results than the static analysis for storey displacements, drifts, shear forces, and bending moments. Specifically, dynamic displacements were over 2.5 times higher and bending moments were around 2 times higher than the static analysis results.
Prestressing is a technique where tension is applied to concrete before hardening to improve its performance. There are two main types - pre-tensioning and post-tensioning. Pre-tensioning involves tensioning steel tendons before casting concrete, while post-tensioning tensions tendons after casting. There are losses in prestress over time from factors like elastic shortening, shrinkage, creep, and steel relaxation. Proper materials and design are needed to account for these losses and ensure structures perform as intended.
Analysis and design of shear wall transfer beam structurephamtraoag
The document analyzes the stress behavior of shear walls and transfer beams due to their interaction. It presents a finite element analysis of a 22-story building model consisting of shear walls, transfer beams, and columns. Two analyses are performed: 1) With vertical loads only to verify the stress behavior matches previous research. 2) With both wind loads and vertical loads to observe stress behavior differences and obtain results for transfer beam design. Based on the second analysis, the transfer beam reinforcement is designed according to CIRIA Guide 2:1977 design standards.
Proposal defence slide on Analysis & Design of Multistoreylochan Shrestha
The document presents a structural analysis and comparison of design codes for a proposed 5.5 story reinforced concrete frame hospital building in Kathmandu, Nepal. It describes the building location, dimensions, structural system and objectives of analyzing the building using SAP2000 software and designing it according to Nepal's NBC and India's IS seismic codes. It also provides background on building analysis and design methods, factors of safety, load combinations specified in the two codes and their provisions for seismic analysis using the seismic coefficient and response spectrum methods.
The document provides an overview of prestressed concrete structures including:
- Definitions of prestressing where internal stresses counteract external loads.
- The key terminology used including tendons, anchorage, pretensioning vs post-tensioning.
- The materials used including cement, concrete, and steel types.
- The stages of loading and advantages of prestressing over reinforced concrete.
- Details of pretensioning and post-tensioning systems including equipment, processes, and differences between the two methods.
This document provides a summary of steel columns, including:
1. It defines steel columns and their key characteristics such as shape, load bearing capacity, and connections.
2. It classifies columns based on cross-sectional shape, loading type, reinforcement, and slenderness ratio.
3. It discusses effective length, slenderness ratio, column bases, and provides examples of calculating load capacity.
This document discusses the earthquake analysis of a 4-storey reinforced concrete building located in seismic zone IV using both manual calculations and STAAD Pro software. Static and dynamic analysis methods are used to calculate the base shear. For the static analysis, the base shear from manual calculations is 99.93 kN while from STAAD it is 87.88 kN. For the dynamic analysis, the manual base shear is 80.93 kN and from STAAD it is 83.89 kN. The results show that static manual calculations provide a more conservative base shear value compared to the other methods. Recommendations are made to further analyze irregular structures and consider nonlinear behavior.
The document discusses structural dynamics and analysis of multi-degree of freedom systems. It covers key concepts such as dynamic differential equations, natural frequencies, damping, modal analysis, and different analysis methods including direct integration and frequency-based approaches. Linear dynamics allows use of natural modes of vibration while nonlinear dynamics accounts for large motions and changing geometry. Damping dissipates energy through velocity-dependent forces. Analysis can be performed via direct time integration or modal superposition depending on the problem characteristics and dominant frequencies.
This is an Introductory material for those who want to understand the basic difference between linear and nonlinear analysis in the context of civil and structural engineering.
Forwarded PPT-2 - Introd of SDOF Free Vib- impotance n Basics.pptxCIV2137AsmuddinKhan
This document summarizes the contents to be covered in the free vibration of single degree of freedom (SDOF) systems. It includes:
1) An introduction to SDOF systems, including examples and developing the generalized equation of motion.
2) Chapter 1 discusses un-damped free vibration of SDOF systems, including the natural period/frequency and response plots.
3) Chapter 2 covers damped free vibration of SDOF systems.
4) Part 1b defines stiffness of structural elements and the concept of equivalent stiffness, applying this to springs in parallel and series configurations.
This document summarizes a study that uses modal pushover analysis (MPA) to estimate the inelastic seismic response of a multi-span concrete bridge. MPA involves performing separate pushover analyses for each vibration mode of the bridge using its mass-weighted modal shape as the lateral load pattern. The peak responses from each mode are then combined using the square root of the sum of squares method to estimate the total seismic demand on the bridge. The study models a 13-span concrete bridge in the SAP2000 nonlinear analysis program and applies MPA to investigate its performance under lateral seismic forces.
A Modal Pushover Analysis on Multi-Span Bridge to Estimate Inelastic Seismic ...IOSR Journals
This document summarizes a study that evaluates the use of modal pushover analysis (MPA) to estimate the inelastic seismic response of a multi-span concrete bridge. MPA accounts for higher mode effects by performing separate pushover analyses for each mode using its respective modal load pattern. Peak modal responses are then combined using the square root of the sum of squares method. The study models a 13-span bridge and applies MPA and nonlinear time history analysis to compare responses. MPA is found to provide a good estimate of deck displacements and plastic hinge rotations, with differences generally within 10% compared to time history analysis results. MPA is concluded to improve accuracy over conventional pushover analysis for estimating seismic demands on long-
Thedynamicbehaviourofastructureiscloselyrelatedtoitsnaturalfrequenciesand
correspondingmodeshapes. Awellknownphenomenonisthatwhenastructureissubjectedto
asinusoidalforceandtheforcingfrequencyapproachesoneofthenaturalfrequenciesofthe
structure,theresponseofthestructurewillbecomedynamicallyamplifiedi.e.resonanceoccurs.
Naturalfrequenciesandtheircorrespondingmodeshapesarerelateddirectlytothestructure’s
massandstiffnessdistribution(foranundampedsystem).
Aneigenvalueproblemallowsthecalculationofthe(undamped)naturalfrequenciesandmode
shapesofastructure. Aconcerninthedesignofstructuressubjecttodynamicloadingistoavoid
orcopewiththeeffectsofresonance.
Anotherimportantaspectofaneigenvaluesolutionisinitsmathematicalsignificance-thatis,it
formsthebasisofthetechniqueofmodesuperposition(aneffectivesolutionstrategytodecouple
acoupleddynamicmatrixequationsystem). Themodeshapematrixisusedasatransformation
matrixtoconverttheproblemfromaphysicalcoordinatesystemtoageneralizedcoordinate
system( modes pace).
In general for an FE model, there can be any number of natural frequencies and corresponding
mode shapes. In practice only a few of the lowest frequencies and mode shapes may be required.
This document discusses various topics related to structural dynamics and soil-structure interaction, including:
1) Mode shapes and how they define the collective behavior of masses in a system.
2) Methods for analyzing dynamically loaded structures, including the frequency-domain method and using Ritz vectors.
3) Factors that influence soil-structure interaction like soil material damping, frequency-dependent stiffness and damping, and kinematic and inertial interactions between structures and soil.
4) References commonly used in the field like textbooks by Chopra and lecture materials from various universities.
This document discusses the variational formulation and Galerkin method for finite element analysis. It begins with an introduction to the differential formulation and principle of virtual work. It then describes how the variational formulation can provide a weaker form of the governing equations that is easier to solve approximately. The document explains that the Galerkin method uses approximated trial functions within the variational framework to find a numerical solution to the problem. Examples are provided for 1D, 2D and 3D problems to illustrate the transition from the strong differential form to the variational/weak form solved using approximated finite element methods.
Vibrations are oscillations in mechanical systems that can occur freely without external forces. While some vibrations cause problems, others can be beneficial. The role of vibration analysis is to model and predict potential problems to inform design modifications before manufacturing. Modeling vibrations accurately is challenging and requires considering different levels of complexity depending on assumptions about system rigidity and mass distributions. Linear systems obey the principle of superposition, which will guide the course's focus on analyzing free and forced vibrations of linear systems using generalized coordinates to describe particle kinematics.
1) The document discusses structural dynamics and defines it as the behavior of structures subjected to dynamic (time-varying) loading.
2) It explains the differences between static and dynamic loading, where dynamic loading induces inertia forces that cause displacement, velocity, and acceleration responses in structures.
3) Several mathematical models are presented to analyze the dynamic behavior of structures, including the single degree of freedom (SDOF) spring-mass model and methods for deriving the equation of motion like Newton's second law.
This document provides an introduction to system dynamics and mathematical modeling of dynamic systems. It defines key concepts such as:
- A system is made up of interacting components that work together to achieve an objective. It has inputs from the environment and outputs responses to those inputs.
- Dynamic systems have outputs that vary over time even if inputs are held constant, due to internal feedback loops within the system.
- Mathematical models of dynamic systems use equations, often differential equations, to describe the system's behavior based on physical laws. The accuracy of a model's predictions depends on how well it approximates the real system.
- Engineering systems like mechanical, electrical, thermal and fluid systems can all be modeled as dynamic systems using appropriate equations
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
The papers for publication in The International Journal of Engineering& Science are selected through rigorous peer reviews to ensure originality, timeliness, relevance, and readability.
1) Dynamics is the study of how structures respond to dynamic or time-varying loads. Static loads do not change over time, while dynamic loads vary with time and can cause displacement, velocity, and acceleration responses in structures.
2) The key differences between static and dynamic loading are that dynamic loading produces inertia forces that cause accelerations, while static loading only produces displacements. These inertia forces contribute significantly to the internal elastic forces that a structure experiences under dynamic loading.
3) Common causes of dynamic effects in structures include initial conditions giving the structure an initial velocity, applied time-varying forces like wind or earthquakes, and support motions like ground shaking during an earthquake.
Hall 2006 problems-encounteredfromuserayleighdampingJuan Camacho
Rayleigh damping is commonly used in finite element models to provide energy dissipation from dynamic loads like earthquakes. However, under certain conditions like nonlinear analysis with softening behavior, the damping forces generated by a Rayleigh damping matrix can become unrealistically large compared to restoring forces, making the analysis unconservative. This paper demonstrates potential problems through examples and proposes bounding the damping forces as a remedy.
Chaos Suppression and Stabilization of Generalized Liu Chaotic Control Systemijtsrd
In this paper, the concept of generalized stabilization for nonlinear systems is introduced and the stabilization of the generalized Liu chaotic control system is explored. Based on the time-domain approach with differential inequalities, a suitable control is presented such that the generalized stabilization for a class of Liu chaotic system can be achieved. Meanwhile, not only the guaranteed exponential convergence rate can be arbitrarily pre-specified but also the critical time can be correctly estimated. Finally, some numerical simulations are given to demonstrate the feasibility and effectiveness of the obtained results. Yeong-Jeu Sun | Jer-Guang Hsieh "Chaos Suppression and Stabilization of Generalized Liu Chaotic Control System" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-3 | Issue-1 , December 2018, URL: http://www.ijtsrd.com/papers/ijtsrd20195.pdf
http://www.ijtsrd.com/engineering/electrical-engineering/20195/chaos-suppression-and-stabilization-of-generalized-liu-chaotic-control-system/yeong-jeu-sun
This document discusses structural dynamics and an experiment involving a shake table. The objective is to determine the natural frequencies, mode shapes, and damping ratios of a scaled structure experimentally. Key concepts covered include the dynamic behavior of single-degree-of-freedom and multi-degree-of-freedom structures. Methods to analyze the time response, increase damping, perform modal analysis, and calculate modal participation factors are also summarized.
Kane/DeAlbert dynamics for multibody system Tadele Belay
The document discusses Kane's method for modeling multi-body systems. It begins with an introduction to multi-body systems and generalized coordinates. It then covers Kane's method which uses generalized speeds and forces to develop equations of motion in a compact form. The method encapsulates both holonomic and non-holonomic constraints. Kane's method is considered superior to other methods for modeling complex multi-body systems. The document provides details on deriving Kane's equations using virtual work principles and generalized speeds and coordinates.
This project aims to analyze the dynamic stability of beams subjected to periodic loads. The student will obtain governing equations in the form of a generalized energy equation and introduce modal damping to study its effects. So far, the critical loads and frequencies have been found for different beam support conditions. The total potential energy equation will be used to determine the non-dimensional frequency and instability regions will be obtained by plotting this against the dynamic load factor. The expected outcomes are to characterize the buckling and vibration behavior of beams and show damping can stabilize dynamics and reduce instability regions.
Evaluation of Vibrational Behavior for A System With TwoDegree-of-Freedom Und...IJERA Editor
Analysis of the vibrational behavior of a system is extremely important, both for the evaluation of operating conditions, as performance and safety reason. The studies on vibration concentrate their efforts on understanding the natural phenomena and the development of mathematical theories to describe the vibration of physical systems. The purpose of this study is to evaluate an undamped system with two-degrees-of-freedom and demonstrate by comparing the results obtained in the experimental, numerical and analytical modeling the characteristics that describe a structure in terms of its natural characteristics. The experiment was conducted in PUC-MG where the data were acquired to determine the natural frequency of the system. We also developed an experimental test bed for vibrations studies for graduate and undergraduate students. In analytical modeling were represented all the important aspects of the system. In order, to obtain the mathematical equations is used MATLAB to solve the equations that describe the characteristics of system behavior. For the simulation and numerical solution of the system, we use a computational tool ABAQUS. The comparison between the results obtained in the experiment and the numerical was considered satisfactory using the exact solutions. This study demonstrates that calculation of the adopted conditions on a system with two-degrees-of-freedom can be applied to complex systems with many degrees of freedom and proved to be an excellent learning tool for determining the modal analysis of a system. One of the goals is to use the developed platform to be used as a didactical experiment system for vibration and modal analysis classes at PUC Minas. The idea is to give the students an opportunity to test, play, calculate and confirm the results in vibration and modal analysis in a low-cost platform
This document provides an overview of a structural theory course. It includes the course objectives, textbook, instructor information, and course schedule. The document then provides sample chapter summaries for topics that will be covered, including introductions to structure systems and loads, supports and reactions, and statics of structures. It outlines key concepts and equations to be covered in each chapter. The goal of the course is to teach students structural analysis and the ability to determine forces and reactions in different structural configurations.
This document outlines Shieh-Kung Huang's seminar presentation on using signal processing techniques to solve vibration problems. It introduces common signal processing techniques like filters, Fourier transforms, and Kalman filters. It then discusses techniques for analyzing vibration signals in the time-frequency domain and time domain. The document presents a case study on using early warning systems and smart isolation to mitigate vibrations affecting sensitive equipment during seismic events. It provides examples of analyzing vibration data from MR dampers and structural testing.
The document discusses earthquake engineering analysis and provides information about earthquakes. It begins with an overview of the 2021 Haiti earthquake and provides figures showing human death tolls and financial losses from major natural hazards. It then covers causes of earthquakes such as tectonic plate movement and convection currents in the mantle. Several devastating historical earthquakes are described such as those in Kobe, Chi-Chi, and the 2004 Indian Ocean earthquake, highlighting their impacts and effects. Tsunamis resulting from earthquakes are also discussed.
Leet, Kenneth, Chia-Ming Uang, and Anne M. Gilbert. Fundamentals of structural analysis. McGraw-Hill, 2010
Chapter 1 Deflections using Energy Methods
Chapter 2 Analysis of Structures using Flexibility Method
Chapter 3 Analysis of Structures using Slope-Deflection Method
Chapter 4 Analysis of Structures using Moment Distribution Method
Chapter 5 Influence Lines for Statically Indeterminate Structures
Chapter 6 Introduction to the General Stiffness Method
Chapter 7 Matrix Analysis of Trusses by the Direct Stiffness Method
Chapter 8 Introduction of Matrix Analysis for Beams and Frames
Leet, Kenneth, Chia-Ming Uang, and Anne M. Gilbert. Fundamentals of structural analysis. McGraw-Hill, 2010
Chapter 1 Deflections using Energy Methods
Chapter 2 Analysis of Structures using Flexibility Method
Chapter 3 Analysis of Structures using Slope-Deflection Method
Chapter 4 Analysis of Structures using Moment Distribution Method
Chapter 5 Influence Lines for Statically Indeterminate Structures
Chapter 6 Introduction to the General Stiffness Method
Chapter 7 Matrix Analysis of Trusses by the Direct Stiffness Method
Chapter 8 Introduction of Matrix Analysis for Beams and Frames
Hibbeler, Russell C. Engineering mechanics: Statics. Pearson Prentice Hall, 2016
Chapter 1 Introduction and General Principles
Chapter 2 Equilibrium of a Particle
Chapter 3 Systems of Forces and Moments
Chapter 4 Equilibrium of a Rigid Body
Chapter 5 Analysis of a Structure
Chapter 6 Internal Forces and Moments
Chapter 7 Friction
Chapter 8 Center of Gravity and Centroid
Chapter 9 Moments of Inertia
Chapter 10 Virtual Work
Hibbeler, Russell C. Engineering mechanics: Statics. Pearson Prentice Hall, 2016
Chapter 1 Introduction and General Principles
Chapter 2 Equilibrium of a Particle
Chapter 3 Systems of Forces and Moments
Chapter 4 Equilibrium of a Rigid Body
Chapter 5 Analysis of a Structure
Chapter 6 Internal Forces and Moments
Chapter 7 Friction
Chapter 8 Center of Gravity and Centroid
Chapter 9 Moments of Inertia
Chapter 10 Virtual Work
Through a 3-week program in South Korea, graduate civil engineering students will learn about smart structures technology through coursework, lectures, labs, and site visits. Students will study hardware, software, data analytics, and applications of smart structures. Hands-on lab and field experiences will complement classroom learning. In addition to technical content, the program includes arts, history, and language activities to immerse students in Korean culture. Students from the US, Korea, Japan, and China will participate in the program funded by various government science and technology organizations.
This 3-week summer school program hosted by National Taiwan University and the National Center for Research on Earthquake Engineering is open to civil engineering graduate students and will take place from July 28th to August 15th, 2014. Students will learn about smart structures technology through coursework, lectures, labs, and site visits addressing hardware, software, data informatics, and applications. Laboratory and field experiences will provide practical, hands-on learning beyond the classroom. Students from various countries in Asia and elsewhere will participate in the culturally immersive program and gain global experience.
Embedded machine learning-based road conditions and driving behavior monitoringIJECEIAES
Car accident rates have increased in recent years, resulting in losses in human lives, properties, and other financial costs. An embedded machine learning-based system is developed to address this critical issue. The system can monitor road conditions, detect driving patterns, and identify aggressive driving behaviors. The system is based on neural networks trained on a comprehensive dataset of driving events, driving styles, and road conditions. The system effectively detects potential risks and helps mitigate the frequency and impact of accidents. The primary goal is to ensure the safety of drivers and vehicles. Collecting data involved gathering information on three key road events: normal street and normal drive, speed bumps, circular yellow speed bumps, and three aggressive driving actions: sudden start, sudden stop, and sudden entry. The gathered data is processed and analyzed using a machine learning system designed for limited power and memory devices. The developed system resulted in 91.9% accuracy, 93.6% precision, and 92% recall. The achieved inference time on an Arduino Nano 33 BLE Sense with a 32-bit CPU running at 64 MHz is 34 ms and requires 2.6 kB peak RAM and 139.9 kB program flash memory, making it suitable for resource-constrained embedded systems.
DEEP LEARNING FOR SMART GRID INTRUSION DETECTION: A HYBRID CNN-LSTM-BASED MODELgerogepatton
As digital technology becomes more deeply embedded in power systems, protecting the communication
networks of Smart Grids (SG) has emerged as a critical concern. Distributed Network Protocol 3 (DNP3)
represents a multi-tiered application layer protocol extensively utilized in Supervisory Control and Data
Acquisition (SCADA)-based smart grids to facilitate real-time data gathering and control functionalities.
Robust Intrusion Detection Systems (IDS) are necessary for early threat detection and mitigation because
of the interconnection of these networks, which makes them vulnerable to a variety of cyberattacks. To
solve this issue, this paper develops a hybrid Deep Learning (DL) model specifically designed for intrusion
detection in smart grids. The proposed approach is a combination of the Convolutional Neural Network
(CNN) and the Long-Short-Term Memory algorithms (LSTM). We employed a recent intrusion detection
dataset (DNP3), which focuses on unauthorized commands and Denial of Service (DoS) cyberattacks, to
train and test our model. The results of our experiments show that our CNN-LSTM method is much better
at finding smart grid intrusions than other deep learning algorithms used for classification. In addition,
our proposed approach improves accuracy, precision, recall, and F1 score, achieving a high detection
accuracy rate of 99.50%.
KuberTENes Birthday Bash Guadalajara - K8sGPT first impressionsVictor Morales
K8sGPT is a tool that analyzes and diagnoses Kubernetes clusters. This presentation was used to share the requirements and dependencies to deploy K8sGPT in a local environment.
Using recycled concrete aggregates (RCA) for pavements is crucial to achieving sustainability. Implementing RCA for new pavement can minimize carbon footprint, conserve natural resources, reduce harmful emissions, and lower life cycle costs. Compared to natural aggregate (NA), RCA pavement has fewer comprehensive studies and sustainability assessments.
Redefining brain tumor segmentation: a cutting-edge convolutional neural netw...IJECEIAES
Medical image analysis has witnessed significant advancements with deep learning techniques. In the domain of brain tumor segmentation, the ability to
precisely delineate tumor boundaries from magnetic resonance imaging (MRI)
scans holds profound implications for diagnosis. This study presents an ensemble convolutional neural network (CNN) with transfer learning, integrating
the state-of-the-art Deeplabv3+ architecture with the ResNet18 backbone. The
model is rigorously trained and evaluated, exhibiting remarkable performance
metrics, including an impressive global accuracy of 99.286%, a high-class accuracy of 82.191%, a mean intersection over union (IoU) of 79.900%, a weighted
IoU of 98.620%, and a Boundary F1 (BF) score of 83.303%. Notably, a detailed comparative analysis with existing methods showcases the superiority of
our proposed model. These findings underscore the model’s competence in precise brain tumor localization, underscoring its potential to revolutionize medical
image analysis and enhance healthcare outcomes. This research paves the way
for future exploration and optimization of advanced CNN models in medical
imaging, emphasizing addressing false positives and resource efficiency.
Optimizing Gradle Builds - Gradle DPE Tour Berlin 2024Sinan KOZAK
Sinan from the Delivery Hero mobile infrastructure engineering team shares a deep dive into performance acceleration with Gradle build cache optimizations. Sinan shares their journey into solving complex build-cache problems that affect Gradle builds. By understanding the challenges and solutions found in our journey, we aim to demonstrate the possibilities for faster builds. The case study reveals how overlapping outputs and cache misconfigurations led to significant increases in build times, especially as the project scaled up with numerous modules using Paparazzi tests. The journey from diagnosing to defeating cache issues offers invaluable lessons on maintaining cache integrity without sacrificing functionality.