Search results “Dynamic analysis time history”
SAP2000 Nonlinear Dynamic Analysis
This workshop will provide a hands-on experience on using SAP2000 for estimating response of structure subject to dynamic loads. A simple steel moment-frame structure will be used to demonstrate steps involved in performing modal, pushover, response-spectrum, and response time-history analysis. Different options available in SAP2000 to capture nonlinear behavior of structure and their effects on structural response will also be discussed. Presentation and supporting materials are available here: http://www.manishkumar.org/resources/softwares/SAP2000/MyTutorial/NDA/SAP2000_Nonlinear_Dynamic_Analysis.pdf http://www.manishkumar.org/resources/softwares/SAP2000/MyTutorial/NDA/Files.zip Note: The scale factor in nonlinear response history analysis case should be 0.01 (I first assigned it 9.81, and then 0.1) to convert the values in ground motion file from cm/sec2 to m/sec2.
Views: 26220 maksins
SAP2000 - 11 Modal Time History Analysis: Watch & Learn
Learn about the SAP2000 structural analysis and design program. Copyright 2011 Computers and Structures, Inc. Visit http://www.csiberkeley.com for more information.
Views: 21224 DECODE BD
Time History Analysis in Etabs 2015
Time History Analysis in Etabs 2015 deals with the procedure to conduct time history analysis in etabs 2015 on a G+6 building. The tutorial explains the time history analysis by assigning the ground motion along both axis. Etabs 2015 provides the option of defining the time history function and scaling the defined time history case for analysis with respect to target response spectrum.Target response spectrum is defined as per ASCE 7-10 which is a predefined option in etabs 2015.In etabs 2015,linear time history analysis can be performed by linear modal analysis method and non-linear time history analysis by direct integration method.This tutorial deals with conducting the linear modal time history analysis in etabs 2015.Tutorial consist of following steps (1) Defining the time history function 4:22 (2) Defining the target response spectrum 8:49 (3) Matching the time history with target response spectrum 10:18 (4) Assigning scaled time history as load case 15:46 To subscribe the channel https://www.youtube.com/channel/UCPVRM5dscZfoQluTvhHr0Ww?sub_confirmation=1 Visit our website for more: www.civilknowhow.com
Views: 33424 Civilknowhow Tutorials
Seismic Analysis Lecture #5 - Dirk Bondy, S.E.
Dynamic modal response spectrum analysis Part 1.
Views: 10188 dirk bondy
Etabs-Day-37(Time history Analysis in Hindi)
Etabs-Day-37(Time history Analysis in Hindi) csi,etabs,etabs 2015,2013,building,seismic loads,load combination,envelope,Mass source,earthquake,Base shear,seismic analysis,structures,engineering,civil engineering,structural,how to,apply earthquake,CSI,ETABS,Structural Analysis,Building Analysis,Steel Design,Concrete Design,Shearwall Design,Dynamic Analysis,Computers and Structures,Finite Elements analysis,Structural Software,Building Design,equivalent method etabs,eismic Dynamic,esponse Spectrum
Views: 3664 videos world
Advanced Dynamic Time History Analysis-STAAD.Pro V8i
* Learn when you have time at your own convenience. * If you don't understand once, simply rewind and watch again...& again... & again...till you understand. * Learn at your own speed(No problem of trying to catch-up with fast learners or waiting for slower students) * No reading involved- Watch & Learn fast. * Cost of training is at least 1/4th as compared to classroom training/instructor led training. * Course prepared by 10-15 years of industry experts which means that you get trained by top professionals. * Time Saving- No traveling to institute and back
Time History Analysis In Staad Pro v8i - Structures under Seismic Accelerations
Time History Analysis In Staad Pro v8i - Structures under Seismic Accelerations http://civildigital.com/time-history-analysis-staad-pro-v8i-structures-seismic-accelerations/ Analysis of a structure, applying data over increment time steps as a function of: --Acceleration --Force --Moment, or --Displacement It provides the response of a structure over time during and after the application of a load. The Time History Response of a structure is simply the response (motion or force) of the structure evaluated as a function of time including inertial effects. Stage One Time History Function Definition Time Step Time Increments or Δt used for analysis. Output time-step size should be small enough to provide sufficient resolution for analysis. The required resolution is dependent upon the characteristics of applied loading and such structural properties as the natural periods. The sufficiency of resolution may be determined by decreasing the time-step size until it is small enough to not affect results. Function Definition Analysis Parameters Arrival Time is the time at which a load assignment begins Can be positive, negative, or zero Begins at time zero, by default Portion of the input which occurs before time zero is ignored for negative arrival time eg: an arrival time of -5 will neglect the first 5sec of the input function. When load type is set to Accel, the scale factor should be specified to produce the acceleration desired in the current units when multiplied with function. If function is in the current units, the scale factor should be set to 1.0. eg: if time-history data is in cm/sec/sec, and current units are ft/sec/sec, then a scale factor of 1ft / 30.48cm = 0.0328 should be used.
Views: 25077 OnlineCivilDigital
Staad pro-day-23(dynamic analysis)
Hello, Every one this is Videosworld Channel that provides online Civil Engineering Software training.my aim to give the tutorial in a simple way in both language Hindi And English. These are the software that I will teach.. Autocad Microsoft Office ( Excel, Power Point, Word ) Revit STAAD Pro SAP 2000 ETABS Google Sketchups 3d Home Architect 3d Max Bently Road Network recon Sap2000 tekla safe MX road GIS ansys abacus in hindi and english tutoriala
Views: 1584 videos world
Dynamic analysis by Sap 2000 د/ عاطف العراقى
شرح طريقة إدخال الأحمال الديناميكية ع ساب 2000 للدكتور عاطف العراقى
Views: 5877 Fatimah Ibrahim
Time history analysis - dynamic response
Dynamic response for sinusoidal forcing
Views: 1213 angrypom
SAP2000 - 29 Fast Nonlinear Analysis: Watch & Learn
Learn about the SAP2000 structural analysis and design program. Copyright 2014 Computers and Structures, Inc. Visit http://www.csiamerica.com for more information.
High Speed to Efficient Design (HS2ED) - Dynamic Analysis
01. Abstract In this webinar we will focus on bridge design for one of the most popular and efficient ways of transporting passengers or cargo for long-haul services, namely high-speed rail. Given the strict requirements for the design of high-speed railway bridges, the complexity of the design process increases significantly compared to those for normal railway. The emphasis in this session will be put on dynamic analysis and on the generation and application of loads coming from high-speed trains. 02. Featured Topics 1. Generation of high-speed train load data 2. Considerations for time history analysis 3. Comparison of dynamic and static train load effect 4. Assessment of structural response to dynamic actions 03. Recommended to engineers and academics interested in: - Learning about the design of bridges for high-speed rail - Working on bridge designs that require dynamic analysis - Improving their knowledge of finite element analysis
Seismic Modal Response Spectrum Analysis in Etabs 2015
This is another tutorial showing how to conduct a seismic modal response spectrum analysis in Etabs 2015 for a concrete multistory building according to EN1998-1-1:2004. Enjoy!!!
Views: 11139 Endri Zhuleku
complete time history of base isolated building using (lead rubber) in SAP2000 part 1
This video show step by step of time history analysis of base isolated building. earthquake form file download link: https://drive.google.com/open?id=0B7q4TumriHixd1BHUWltV0lLU0k twitter: https://twitter.com/ajay1494 instagram: https://www.instagram.com/ajaysingh09/ facebook: https://www.facebook.com/ajaydj93 About: I am B.E civil engineering student i make video what i love
Views: 11470 Ajay Singh
Time history analysis
video shows time history analysis in SAP2000.
Views: 7599 Yogesh Shermale
Dlubal Webinar: Nonlinear Time History Analysis in RFEM (USA)
Content: - Overview of dynamic analysis in RFEM and the Dynam Pro add-on modules - Natural frequency analysis of a structure using RF-DYNAM Pro - Natural Vibrations - Linear time history analysis with machine induced vibrations using RF-DYNAM Pro - Forced Vibrations - Nonlinear time history analysis using RF-DYNAM Pro - Nonlinear Time History https://www.dlubal.com/en-US/solutions/application-areas/nonlinear-dynamic-analysis-software https://www.dlubal.com/en-US/products/rfem-and-rstab-add-on-modules/dynamic-analysis https://www.dlubal.com/en-US/support-and-learning/learning/webinars https://www.dlubal.com/en-US
Time History Analysis
Theoretical background and implementation of time history analysis in Robot
Time history sap2000
Time history analysis in sap2000
Views: 42584 preethan dhara
Seismic Response-History Analysis for the Design and Assessment of Buildings
http://skghoshassociates.com/ For the full recording: http://www.secure.skghoshassociates.com/product/show_group.php?group=60150128v This web seminar begins with a discussion about the choices provided by ASCE 7-10 for dynamic analysis: modal response spectrum analysis, linear time history analysis, and nonlinear time history analysis, with the advantages and shortcomings of each pointed out. Ground motion selection, scaling, modeling and acceptance criteria as they relate to time history analysis are explained and frequently asked questions are answered. A preview of the newly reorganized Chapter 16, Seismic Response-History Procedures, is presented highlighting the many ways it will benefit the user. The reorganized chapter will be part of ASCE 7-16. Available software for time-history analysis are also covered. For the full recording: http://www.secure.skghoshassociates.com/product/show_group.php?group=60150128v
Views: 952 SKGAssociates
SOLIDWORKS Simulation - Linear Dynamics Dampening Case Study
See more at: http://www.goengineer.com/products/solidworks-simulation/ Learn how to set up a Modal Time History Linear Dynamics analysis to find out how long it takes your device to stop vibrating after it is hit with a shock wave in SOLIDWORKS Simulation. Quick Tip presented by Taran Packer of GoEngineer. About GoEngineer: GoEnginneer delivers software, technology and expertise that enable companies to unlock innovation and deliver better products faster. With more than 30 years experience and thousands of customers in high-tech, medical, machine design, energy and other industries, GoEngineer provides best-in-class design solutions from SOLIDWORKS, Stratasys, CAMWorks and Agile PLM. http://www.goengineer.com http://www.facebook.com/goengineer http://www.twitter.com/goengineer http://www.linkedin.com/goengineer https://plus.google.com/+goengineer
Views: 1330 GoEngineer
Assess Dynamic Response with Spectral and Time History Analysis
Determine fatigue life through full non-linear soil and structural analysis, and dynamic spectral/time history fatigue analysis. Perform spectral wind fatigue calculations including gust effects and spatial correlation. Determine fatigue damage due to wave action over time. This capability can be found in SACS Fatigue. For more information on our Offshore Structural Analysis applications, please visit https://www.bentley.com/en/products/product-line/offshore-structural-analysis-software
ANSYS TUTORIAL, dynamic analysis on beam  problem HINDI|URDU
Transient Dynamic Analysis in ANSYS Mechanical. A transient dynamic analysis is used to determine the response of a structure subjected to a time-dependent loading considering inertia and damping effects. It is often referred to as a time-history analysis. At Release 14.0, ANSYS Mechanical can perform a time-transient analysis using the full method or the modal superposition method. The full method uses the full system matrices to calculate the transient response at each solution point. The mode-supe method scales the mode shapes and sums them to capture the dynamic response. Share, Support, Subscribe!!! Twitter: https://twitter.com/seeandgrow Facebook: https://www.facebook.com/seeandgrow.byabdulsamad Instagram: https://www.instagram.com/seeandgrow/
Views: 199 see and grow
ETABS - 22 Response Spectrum Analysis: Watch & Learn
Learn about the ETABS building analysis and design program. Copyright 2016 Computers and Structures, Inc. Visit http://www.csiamerica.com for more information.
Time-history Dynamic Analysis of a 3-storey CLT structure - Kobe JMA - PGA=0.15g
Structural response of a 3-storey Cross Laminated Structure under the Kobe JMA N-S component scaled to a peak ground acceleration of 0.15g. Tests conducted as part of the SOFIE project.
Views: 152 Aether Engineering
Etabs 2015 - Response Spectrum Analysis
Etabs 2015 advanced tutorial deals with the response spectrum analysis which is a method of seismic analysis considered for irregular or tall buildings.The tutorial is based on codal provisions listed according to ASCE 7- 05.Steps illustrated in the tutorial can be followed for other international earthquake codes.Following are explained in the tutorial: (1) Defining load pattern 2:22 (2) Defining Mass Source 3:25 (3) Modal cases 3:49 (4) Response spectrum function 4:47 (5) Defining scale factor 7:07 (6) Modal participation mass ratio 10:16 (7) Scaling of response spectrum base shear 13:18 Tutorial starts with an introductory explanation about response spectrum analysis.The load patterns and mass source are defined according to ASCE 7-05. For detailed explanation on this part , beginners tutorial can be referred.In the following steps modal cases and response spectrum function are defined and while defining the load cases,the method of scaling the response spectrum function is explained.After the analysis, modal participation mass ratio check is conducted to make sure that the number of modes considered for the analysis is sufficient or not.In the response spectrum base shear check,the obtained response spectrum base shear is scaled up to 85 % of the static base shear for the dynamic analysis. To subscribe the channel https://www.youtube.com/channel/UCPVRM5dscZfoQluTvhHr0Ww Like us in facebook: https://www.facebook.com/civilknowhow Visit our website for more: https://www.civilknowhow.com
Views: 75562 Civilknowhow Tutorials
Dynamic Analysis of Footbridge to Eurocode
This course will introduce pertinent structural implications for dynamic pedestrian vibration analysis of footbridges. The course will take you through the basics of dynamic analysis, free vibration analysis, Eurocode specific dynamic load models and performing a serviceability comfort criteria check to Eurocodes. This webinar is suited for structural engineers who wish to carry out the vibration analysis checks to Eurocodes on footbridges. Course Contents: Introduction • Basics of Dynamic Analysis • Workflow for numerical dynamic analysis Free Vibration analysis of footbridges • Mass and stiffness consideration • Vibration mode shapes • Natural frequency of the structure • Mass Participation Eurocode Dynamic Pedestrian Actions • Walking, Jogging and Crowd conditions • Application of Eurocode in numerical analysis • Time varying moving loads on footbridge Dynamic (Time History) Analysis results • Acceleration vs time plots • Peak acceleration limit check to Eurocodes Vibration Control on Footbridges
Views: 5648 Midas UK
Time History Analysis in RISA
This webinar will demonstrate how to use the Time History feature in RISA-3D. Examples will include the effects of dynamic loading from equipment, blast loading and seismic loads on structures.
Views: 4920 RISA Tech, Inc.
[MIDAS Expert Webinar] Dynamic Analysis for High Speed Two HS2
The vibration evaluation of bridges by high-speed trains is performed by inputting the train load defined by the Train Load Generator function to the dynamic nodal load according to the speed of the train, performing the linear time history analysis to calculate the maximum acceleration in the gravity direction of the bridge.
Nonlinear Time History with Slope Stability Coupled Analysis
GTS NX for dynamic coupled analysis
Views: 1331 MIDAS LA
Seismic Analysis of Bridges - midas Civil Technical Webinar
Seismic analysis and design remains a topic of slight controversy among engineers today. Delivering for the rigorous requirements for seismic analysis stipulated by most codes is usually time consuming and adds to overall project costs. Consequently many engineers in non-seismic zones simply prefer to apply nominal design provisions without much calculation. But with the advent of modern codes as well as in the wake of several recent seismic catastrophes, engineers are reconsidering their perspective on seismic resistance for structures. This web session will aim to highlight the basic requirement of seismic analysis and walk the attendees through the various methods available for Seismic analysis of Bridge structures, simultaneously demonstrating the capabilities of midas Civil in handling these kinds of analysis. Learning Objective: 1. Selection of suitable method for seismic analysis and design 2. Response Spectrum & Eigenvalue Analysis 3. Pushover Analysis 4. Inelastic Time History Analysis
SAP2000   11 Modal Time History Analysis
The SAP name has been synonymous with state-of-the-art analytical methods since its introduction over 30 years ago. SAP2000 follows in the same tradition featuring a very sophisticated, intuitive and versatile user interface powered by an unmatched analysis engine and design tools for engineers working on transportation, industrial, public works, sports, and other facilities. From its 3D object based graphical modeling environment to the wide variety of analysis and design options completely integrated across one powerful user interface, SAP2000 has proven to be the most integrated, productive and practical general purpose structural program on the market today. This intuitive interface allows you to create structural models rapidly and intuitively without long learning curve delays. Now you can harness the power of SAP2000 for all of your analysis and design tasks, including small day-to-day problems. Complex Models can be generated and meshed with powerful built in templates. Integrated design code features can automatically generate wind, wave, bridge, and seismic loads with comprehensive automatic steel and concrete design code checks per US, Canadian and international design standards. Advanced analytical techniques allow for step-by-step large deformation analysis, Eigen and Ritz analyses based on stiffness of nonlinear cases, catenary cable analysis, material nonlinear analysis with fiber hinges, multi-layered nonlinear shell element, buckling analysis, progressive collapse analysis, energy methods for drift control, velocity-dependent dampers, base isolators, support plasticity and nonlinear segmental construction analysis. Nonlinear analyses can be static and/or time history, with options for FNA nonlinear time history dynamic analysis and direct integration. From a simple small 2D static frame analysis to a large complex 3D nonlinear dynamic analysis, SAP2000 is the easiest, most productive solution for your structural analysis and design needs.
Views: 1282 Murat Feyzifar
Mod-05 Lec-20 Response Spectrum Method of Analysis
Seismic Analysis of Structures by Dr. Ashok Gupta & Dr. T.K. Datta,Department of Civil Engineering,IIT Delhi.For more details on NPTEL visit http://nptel.ac.in
Views: 11463 nptelhrd
Nonlinear time history analysis with seismic isolators: Midas Civil Tutorial for Basic Users
You can download trial for midas Civil and follow the tutorial at: http://en.midasuser.com This tutorial shows how to perform nonlinear boundary time history analysis with seismic isolators in midas Civil software. The modeling process is omitted, you can download this model at: "product tutorial" section of the official website. The procedure of the analysis will follow: 1. Define the properties of nonlinear links 2. Input nonlinear links 3. Enter the analysis condition for time history analysis 4. Perform nonlinear time history analysis 5. Check analysis results
ABAQUS Framed Reinforced Concrete Multi-Storey Structure Under Earthquake
This video presents one of the ways of modelling framed reinforced concrete multi-storey structures subjected to earthquakes in the commercial Finite Element program Abaqus. Details ↓ ↓ ↓ Pre-Processing (Modelling) 00:00:00 Parts, Materials, Profiles, Sections, General Geometry of Structure 00:16:10 Assembly, Instances, Surfaces, Partition Planes, Sets, Constraints 01:01:53 Amplitudes, Steps, Field Output, Loads, Boundary Conditions 01:13:35 Mesh, Corrections Post-Processing (Visualization of Results) 01:39:56 Stresses and Strains in Concrete 01:59:34 Displacements and Drifts 02:24:16 Stresses in Rebars 02:27:10 Failure Mechanism, Limitations, Conclusion Link to Excel file https://drive.google.com/open?id=1kEuwf1B3OBbRhv2IdKTtr0DQ-_23i7-Y Link to the report http://projekter.aau.dk/projekter/en/studentthesis/nonlinear-analysis-of-earthquakeinduced-vibrations(a8b31279-aad4-4950-8797-b1343262b54b).html Link to the PowerPoint Presentation https://drive.google.com/open?id=17nNN43Kec5iq48_mOprIYY5Wa_rZQg4w Link to ABAQUS Reinforced Concrete Beam (stirrups included) video https://www.youtube.com/watch?v=XzJC8Nqf8vo Connect and stay updated Facebook: https://www.facebook.com/vladinculet LinkedIn: https://www.linkedin.com/in/vladinculet Email: [email protected] Copyrighted content, only available at this source. ©
Views: 89500 Vlad Inc.
SOLIDWORKS Simulation - Sine Sweep Dynamics Tutorial
See more at: http://www.goengineer.com or http://www.goengineer.com/products/solidworks-simulation/ or http://www.goengineer.com/govideochannel/ Learn about conducting a sine sweep test simulation with external loading using the Harmonics module in Linear Dynamics, SOLIDWORKS Simulation Premium. The tutorial is about 12 minutes and includes an overview of typical workflow for Harmonic analysis. Static analysis; estimate of spring constant; estimate of vibration frequency; conduct frequency and modal survey; run harmonic dynamic analysis. QuickTips video presented by Tony Botting of GoEngineer.
Views: 38178 GoEngineer
ANSYS: Transient analysis of Bridge
Step by step procedure of how to do transient structural analysis (varying load/force with time) of a bridge ANSYS 13 workbench. Visit http://www.teachkart.com/ for complete tutorial ANSYS Rigid dynamic : four bar linkage mechanism : universal joint working animation: Ansys Tutorial for Beginners | Ansys Tutorial Structural | Ansys Structural Tutorial | Ansys Stress Analysis Tutorial
Views: 146276 TEACHKART.COM
Dynamic analysis of a beam subjected to a transient force time history
Calculation of the deflection, reaction forces, energy of a beam subjected to a transient dynamic force time history using the Ingeania SDOF Calculator
Views: 68 Ingeania Com
Dynamic analysis of structures with DIANA
This session gives a clear overview of different methods that DIANA offers to perform the dynamic analysis of civil engineering structures. In the first part the dynamic specific modelling aspects such as mass, damping, acceleration loading and waves, are explained. The second part will cover the details of Fluid-Structure Interaction (FSI), e.g. added mass and damping. The final part will demonstrate the available analysis types for dynamic analysis in DIANA; Free vibration eigenvalue analysis, response spectrum analysis (RSA), modal and direct frequency response analysis, transient dynamic (time history) analysis, and Hybrid Frequency-Time Domain (HFTD) analysis with associated and their specific dynamic output results.
Views: 491 DIANA FEA BV
Time history analysis with AxisVM - Seismic effect
A short animation presents the capabilities of the dynamic module in AxisVM
Views: 132 Inter-CAD Kft.
Dlubal Webinar: Time-History Analysis in RFEM - Induced Vibrations (USA)
Content: - Overview and features of RFEM and the dynamic add-on modules - Natural frequency analysis utilizing RF-DYNAM Pro - Natural Vibrations - Time-history analysis utilizing RF-DYNAM Pro - Forced Vibrations - Example 1: Machine induced vibrations - Example 2: Blast analysis https://www.dlubal.com/en-US/solutions/application-areas/dynamic-and-seismic-analysis-software https://www.dlubal.com/en-US/products/rfem-and-rstab-add-on-modules/dynamic-analysis https://www.dlubal.com/en-US/support-and-learning/learning/webinars https://www.dlubal.com/en-US
Views: 1232 Dlubal Software, Inc.
Time History data
How to get Time History data of an Earthquake
Views: 2509 P. Basavaraj
Experimental Research in Aerospace Structural Dynamics ~ 1962 NASA Langley; Aeronautical Engineering
NASA & Space Miscellany playlist: https://www.youtube.com/playlist?list=PL_hX5wLdhf_K3mK1TZNCkmdD-JMZYGew1 Aircraft playlist: https://www.youtube.com/playlist?list=PL23A1203602337689 more at http://scitech.quickfound.net 'Archival film on structural dynamics and flutter from several tests.' NASA Langley Film #8213 Originally a public domain film from NASA, slightly cropped to remove uneven edges, with the aspect ratio corrected, and one-pass brightness-contrast-color correction & mild video noise reduction applied. The soundtrack was also processed with volume normalization, noise reduction, clipping reduction, and/or equalization (the resulting sound, though not perfect, is far less noisy than the original). https://en.wikipedia.org/wiki/Structural_dynamics Wikipedia license: http://creativecommons.org/licenses/by-sa/3.0/ Structural analysis is mainly concerned with finding out the behavior of a physical structure when subjected to force. This action can be in the form of load due to the weight of things such as people, furniture, wind, snow, etc. or some other kind of excitation such as an earthquake, shaking of the ground due to a blast nearby, etc. In essence all these loads are dynamic, including the self-weight of the structure because at some point in time these loads were not there. The distinction is made between the dynamic and the static analysis on the basis of whether the applied action has enough acceleration in comparison to the structure's natural frequency. If a load is applied sufficiently slowly, the inertia forces (Newton's first law of motion) can be ignored and the analysis can be simplified as static analysis. Structural dynamics, therefore, is a type of structural analysis which covers the behavior of structures subjected to dynamic (actions having high acceleration) loading. Dynamic loads include people, wind, waves, traffic, earthquakes, and blasts. Any structure can be subjected to dynamic loading. Dynamic analysis can be used to find dynamic displacements, time history, and modal analysis. A dynamic analysis is also related to the inertia forces developed by a structure when it is excited by means of dynamic loads applied suddenly (e.g., wind blasts, explosion, earthquake). A static load is one which varies very slowly. A dynamic load is one which changes with time fairly quickly in comparison to the structure's natural frequency. If it changes slowly, the structure's response may be determined with static analysis, but if it varies quickly (relative to the structure's ability to respond), the response must be determined with a dynamic analysis. Dynamic analysis for simple structures can be carried out manually, but for complex structures finite element analysis can be used to calculate the mode shapes and frequencies... Modal analysis A modal analysis calculates the frequency modes or natural frequencies of a given system, but not necessarily its full-time history response to a given input. The natural frequency of a system is dependent only on the stiffness of the structure and the mass which participates with the structure (including self-weight). It is not dependent on the load function. It is useful to know the modal frequencies of a structure as it allows you to ensure that the frequency of any applied periodic loading will not coincide with a modal frequency and hence cause resonance, which leads to large oscillations. The method is: - Find the natural modes (the shape adopted by a structure) and natural frequencies - Calculate the response of each mode - Optionally superpose the response of each mode to find the full modal response to a given loading Energy method It is possible to calculate the frequency of different mode shape of system manually by the energy method. For a given mode shape of a multiple degree of freedom system you can find an "equivalent" mass, stiffness and applied force for a single degree of freedom system. For simple structures the basic mode shapes can be found by inspection, but it is not a conservative method...
Views: 1402 Jeff Quitney