Response Spectrum Analysis Example

txt) or read online for free. Elastic Response Spectrum. In such areas, the normally employed used procedure is response spectrum analysis method (ASCE 7-05 Section 162) which is also acceptable by IBC. Response-spectrum analysis provides insight into dynamic behavior by measuring pseudo-spectral acceleration, velocity, or displacement as a function of structural period for a given time history and level of damping. Site-specific response spectra 3-1 e. 5% damping. • NC-3600 - Design and analysis for Class 2 pipes. Seismic analysis -Modal spectral analysis It defines the seismic behavior of the structure as the superposition of n‐modes of vibration. Pivotal Response Training (PRT) is a method of systematically applying the scientific principles of applied behavior analysis (ABA) to teach learners with autism spectrum disorders (ASD). 5 and the design base shear in Section 12. Response Spectra Analysis using ETABS. First column is time and second column is acceleration in g. DDAM Background (Continued). It combines the pushover analysis of a multi‐degree‐of‐freedom (MDOF) model with the response spectrum analysis of an equivalent single‐degree‐of‐freedom (SDOF) system. target response spectrum that links nonlinear dynamic analysis back to probabilistic seismic hazard analysis for ground motion selection. 1 Analysis assumptions Basic assumptions for estimation of seismic loads acting on the wind turbine support structures are. Earthquake loads are defined in the form of curves called "acceleration response spectra" which is the. Therefore, an acceler ation response spectrum. SATISH 1998B4A2437 Under the supervision of Dr. Draft 6 Steps 4 to 6 are performed as an iterative response spectrum analysis process. This is a function to generate elastic response spectra of an earthquake. The vibration response spectrum has many uses. RESPONSE SPECTRUM ANALYSIS 15-3 Where, the three Mode Participation Factors are defined by n Mi T pni = -φ in which i is equal to x, y or z. Response spectrum analysis is performed using the response spectrum of Fig. Earthquake loads are defined in the form of curves called "acceleration response spectra" which is the. dat file for a Response Spectrum analysis illustrates the formation of the Displacement, Velocity and Acceleration results. Earthquake design spectra Given a earthquake ground acceleration, there is no difficulty to compute response using Newmark's method as the previous example. The analysis example shows the calculation of a target PSD function related to the modified DRS from RG 1. The maximum value of the integral in (13) will. Single model for - linear static analysis - linear response spectrum analysis - linear time history analysis - nonlinear time history analysis - nonlinear static pushover analysis - steel and concrete design ; 51 SAP2000/ETABS Pushover Options. Saiid Saiidi, have made a study to better understand the bridge response due to site response effect. A modal analysis of the structure is carried out to obtain mode shapes, frequencies & modal participation factors. Only applies to base excitation multi-point response spectrum analysis (SPOPT, MPRS) and power spectral density analysis (SPOPT, PSD). A relatively simple nonlinear method for the seismic analysis of structures (the N2 method) is presented. Describe the analysis process and requirements for the Equivalent Lateral Force, the Modal Response Spectrum, Linear Response History, and Nonlinear Response History Analysis methods. Several methods are available to predict bridge response to incoherent ground motions, but are typically cost prohibitive to implement in standard bridge designs. 28 Response Spectra as a Useful Design and Analysis Tool for Practicing Structural Engineers. This is a function to generate elastic response spectra of an earthquake. The standard response spectrum analysis (RSA) procedure prescribed in various design codes is commonly used by practicing engineers to determine the seismic demands for structural design purpose. For earthquake-type excitations, a response spectrum method is developed whereby various statistical measures of the equipment response are given directly in terms of the input ground response spectrum. Depending on the period of oscillation, the relating spectral acceleration can be taken directly from the response spectrum (for instance, for determining the foundation shear). Earthquake Resistant Buildings 3. The units of psd are the units of the load squared over frequency as a function of frequency. midas Civil software is used for structural analyses of the bridge including response spectrum analysis, eigen value analysis, large displacement analysis, vehicle load analysis. The analysis of structure by using equivalent static method, time history method and response spectrum method has been surveyed. Response-spectrum analysis seeks the likely maximum response to these equations rather than the full time history. A response spectrum analysis is similar to a random analysis in that the actual loads are unknown. The philosophy of the design is the following. Figure 3 : Acceleration Response Spectrum. The ground motion is usually defined by design response spectra scaled to peak ground accelerations (PGA) for the two design earthquakes described below. Related to Analysis/Design: • Modal Response Spectrum Analysis (Malley) * • Nonlinear Response History Analysis (Haselton) • Diaphragm Analysis and Design (Ghosh) • Rigid Wall/Flexible Diaphragm Buildings (Kelly) • Strength-Based Foundation Design (Johnson) • Foundations on Liquefiable Sites (Bachman). Response spectra can also be used in assessing the response of linear systems with multiple modes of oscillation (multi-degree of freedom systems), although they are only accurate for low levels of damping. - accounting for mode coupling makes the response estimate from these methods more realistic and closer to the exact time history solution Response Spectrum. Calculate design. • Equations of Motion for MDOF Systems • Uncoupling of Equations through use of Natural Mode Shapes • Solution of Uncoupled Equations • Recombination of Computed Response • Modal Response Spectrum Analysis (By Example) • Use of Reduced Number of Modes. The MSRS combination rule estimates the peak structural response in terms of the response spectra of the support motions and a coherency function that characterizes the spatial variability of the ground motion random field. example of smooth spectra is shown in Figure 4 based on a building code design response spectrum for a site of high seismicity. As summarized by Cornell (2006), the UHS is not the response spectrum of ground motion from a single earthquake and therefore has an artificial shape. Details regarding class organization, and Engineering Outreach and Contact Information (Dr. 0 defines global Y as the spectrum direction. match to a probabilistic response spectrum (equal or uniform hazard spectrum, UHS) for design purposes, there may be conservatisms involved in doing so. Draft 6 Steps 4 to 6 are performed as an iterative response spectrum analysis process. The codal provisions as per IS:1893 (Part 1)-2002 code for response spectrum analysis of multi-story building is also summarized. – accounting for mode coupling makes the response estimate from these methods more realistic and closer to the exact time history solution Response Spectrum. Response spectrum analysis is one of the most commonly used analysis methods in seismic design and assessment. It is practical to envelope response spectra such that a smooth curve represents the peak response for each realization of structural period. Zero-Hold Equivalence. Topics: Basis for Response History Analysis. Two major problems must be solved to obtain an approximate response spectrum solution to this equation. Shock Response Spectrum Analysis Introduction. The textual counterpart to Figure. T T1 2 From Response Spectrum: For T1 = 0. Earthquake Resistant Buildings 3. CQC or GMC (Gupta) method • Combination of three ETABS direction by ABS or SRSS method. Obtain modal solution Block. A Response Spectrum Analysis requires the specification of an excitation spectrum, also known as a frequency-acceleration spectrum. It allows the user to create source and background PHA or PI spectra and the associated ARF and RMF files. The purpose of this tutorial is to present this function and give an example of a typical application. Analysis Settings in the example Response Spectrum analysis requested a relatively simplified SRSS mode combination (See Figure 2 above), and ignored more sophisticated settings that might be considered in accurate commercial work, for example: Modes with closely-spaced natural frequencies. Response spectrum analysis is a linear analysis where only linear soil spring can be used. In general, the response spectra analysis procedure is based on the assumption that the dynamic response of a structural model can be approximated as a summation of the responses of the independent dynamic modes of the model. Modeling and analysis of the design example 25 2. midas Civil software is used for structural analyses of the bridge including response spectrum analysis, eigen value analysis, large displacement analysis, vehicle load analysis. Therefore, the mass spectrum is essentially a fingerprint for the molecule. Response spectrum for support excitation; 3. and A2 = 0. It can also be an idfrd object containing frequency-response data. In this study, a site response analysis has been carried out using the bedrock response spectrum from AS1170. Response spectrum analysis can be used to estimate the peak response (displacement, stress, etc. Earthquake Engineering Software The NISEE Software Library CDROM, a collection of research software developed from the 1960s through the early 1990s, is sold out. Introduction. 3 discusses and provides an example for the selection and scaling of ground motion records for use in response history analysis. Example 1/Page 4 Example 1 - Calculation of Design Seismic Force by Static Analysis Method Problem Statement: Consider a four-storey reinforced concrete office building shown in Fig. Seismic Response Spectrum using FFT Basic useage of FFT in R-script Script for usage of FFT and IFFT. Response Spectrum analysis In this example the density of the beam is 1 kg/m^3. Then open the Response Spectrum and insert RS Displacment. For example, the simplest digital filter might average 64 adjacent samples in the original spectrum to produce each sample in the filtered spectrum. In NX Nastran, use: SOL 109 to perform direct transient response analysis. Acceleration Response Spectrum Curves Soil-Structure Interaction Analysis for Bridge. Spectrum is composed by Frequency, Magnitude and Phase, but, if I want to put it into Solidworks (during the Harmonic Analysis), when I change the function curve of my signal, I've noticed the lack of the input "phase"; there is only the column of Frequency and of the Magnitude. Highlights. dat file for a Response Spectrum analysis illustrates the formation of the Displacement, Velocity and Acceleration results. Threat Assessment. Earthquake Design Spectra 5. 8-1 [Spectrum Analysis] Determine the first two natural frequencies and the response of a damped two degree of freedom system subject to a random acceleration with a spectral density function as shown in the figure below. Response-spectrum analysis seeks the likely maximum response to these equations rather than the full time history. Music 318, Winter 2007, Impulse Response Measurement 14 Impulse Response Measurement Analysis 0 10 20 30 40 50 60 70 80 90 100-0. To further clarify, kindly refer my comments below: After performing RS analysis and combining modal results, signs are definitely lost. An eigenvalue analysis has to be performed first to be able to generate the response spectrum. aUnit of Applied Mechanics, University of Innsbruck, 6020 Innsbruck, Austria. In certain situations involving critical or highly complex structures, modal analysis procedures utilizing the elastic response spectrum concept have been employed. specextract can take a stack of input files and generate many spectra in one run of the script. Three different floor plans that are symmetric (SB), monosymmetric (MB), and unsymmetric (UB) with torsional irregularity are taken as sample buildings. The natural frequencies obtained during a Response Spectrum Analysis do not match the Calculate Rayleigh Frequency When Specifying Damping, the Displacements and Forces Remain Same Why are beam graphs not displayed for response spectrum load cases in STAAD. features available in S-FRAME for seismic/dynamic analysis and design. Pure sinusoidal vibration, on the other hand, can be dealt with using time domain methods. Vibration response spectrum in matlab The following Matlab project contains the source code and Matlab examples used for vibration response spectrum. Modal Analysis of a Flat Plate: Produce a MSC/NASTRAN input file and submit for analysis to find the first five natural frequencies and mode shapes. This book is designed for undergraduate and graduate students taking a first course in Dynamics of Structures, Structural Dynamics or Earthquake Engineering. This seminar will cover all aspects related to design ground motions by going first through the probabilistic site specific seismic hazard analysis and the evaluation of the hazard spectrum at rock. Below is an ANSYS Release 10. Design Acceleration The elastic design response spectrum used in the analyses is consistent with that recommended by ATC-40 (1996). This is to convert the spectrum into required units and for the base shear to scale it to an appropriate level. Set options related to response spectrum analysis in Response Spectrum Load Cases. 8 (16 ratings) Course Ratings are calculated from individual students’ ratings and a variety of other signals, like age of rating and reliability, to ensure that they reflect course quality fairly and accurately. of modes to use Spectrum disp, vel, accl, Stiffness damping Random vibration Power Spectral Density 1. The structure of an example ds. In this step, the time data is transformed to the frequency domain. A plot of Y,. Figure 14: Example of positive (top left), negative (top right), and absolute (bottom) shock response spectrum for the primary instance of a transient event. This example illustrates the general procedure for determining the design spectral response acceleration parameters S DS and S D1 from the mapped values of S S and S 1. From what I understand, this means that we have to calculate the response (be it displacement, the difference in displacement, the forces or moment) for each mode first, before we apply the modal combination method such as SQSS, CQC and ABS in order to obtain the total response. In this report, we will refer to shock spectra, also regarded as response spectra. Historically, the shock-response spectrum was initially used to describe transient phenomena, at the time called shocks. 119 shows an example of the response spectrum for a spar in an extreme sea. The ground motion is usually defined by design response spectra scaled to peak ground accelerations (PGA) for the two design earthquakes described below. dat file for a Response Spectrum analysis illustrates the formation of the Displacement, Velocity and Acceleration results. USEE can report response data according to the user-specified output time step. The response spectrum is a plot of the maximum response, as a function of oscillator frequency of an array of Single Degree of Freedom,. Obtain modal solution Block Lancos(missing mass) PCG Lancos(missing mass) Supernode 3. This report presents a numerical method for computing response spectra from strong-motion earthquake records. Using the response spectrum method, a complete solution was found for each of the 40 analyses using the Combination. Carry out the dynamic analysis by using the above mentioned design m3 spectrum. Seismic Analysis of a Reinforced Concrete Building by Response Spectrum Method www. Analysis of Elastic MDOF Systems. (b) Dynamic Analysis Method The design response spectra of IS 1893-2002 given as input in the Define menu > Response Spectrum Functions. Only the maximum response is estimated. Response spectra load cases are define in Response Spectrum cases The damping value is specified which is used to generate the response spectrum curve. Pivotal Response Training (PRT) is a method of systematically applying the scientific principles of applied behavior analysis (ABA) to teach learners with autism spectrum disorders (ASD). Only the masses in both horizontal directions are considered in this example. Seismic Response Spectrum using FFT Basic useage of FFT in R-script Script for usage of FFT and IFFT. That guide requires that the shape of the response spectrum be chosen from the curves shown in Figures 6-5 and 6-6. A comprehensive investigation of the Multiple Support Response Spectrum (MSRS) method for seismic analysis of bridges and other multiply supported structures is presented. Response spectra can also be used in assessing the response of linear systems with multiple modes of oscillation (multi-degree of freedom systems), although they are only accurate for low levels of damping. Carry out the dynamic analysis by using the above mentioned design m3 spectrum. For example, the units of a psd curve for pressure are (psi) 2 / Hz over Hz. - Here Finite Element Approach isused to analyze the dam. Modify for Expected Performance and Equivalent Damping 5. 1 will be numerically solved by Newmark linear method. Response Spectrum Analysis STAAD Pro - URGENT. DDAM for Abaqus performs response spectrum analyses by operating on the results of an Abaqus normal mode frequency extraction. Normal distribution and Correlation; 4. spectrum) The response spectrum method is an approximate, efficient means for predicting response to transient shock excitations. Dynamic Analysis of Linear MDOF Systems : Introduction, modal analysis - Response-history for earthquake excitations using modal analysis - Response spectrum analysis for peak responses - Concept of Caughey damping as a general type of proportional damping. Generally follows ATC-40 FEMA 273 ; Available Pushover Element Types - 3D truss. Earthquake Engineering Analysis and Design 4 1. in Figures 22-1 through 22-6. Generally, the frequency response analysis of a circuit or system is shown by plotting its gain, that is the size of its output signal to its input signal, Output/Input against a frequency scale over which the circuit or system is expected to operate. presents the dynamic time history analysis and response spectrum method of a concrete gravity dam by using STAADPRO. Sample uniform hazard and 10% probability of exceedance in 50 years. In this effort, both basic response spectrum methods and U. Response Spectrum Analysis gives users the ability to perform seismic analysis based on the building properties: natural periods, eigen-modes, mass system, and user inputs: load function and load direction. Related to Analysis/Design: • Modal Response Spectrum Analysis (Malley) * • Nonlinear Response History Analysis (Haselton) • Diaphragm Analysis and Design (Ghosh) • Rigid Wall/Flexible Diaphragm Buildings (Kelly) • Strength-Based Foundation Design (Johnson) • Foundations on Liquefiable Sites (Bachman). SOLIDWORKS Simulation Dynamics. static and dynamic analysis, the results such as Bending moment, Nodal Displacements, Mode shapes are observed, compared and summarized for Beams, Columns and Structure as a whole during both the analysis. In Figure 15 , all six methods of calculating the amplitude of the Shock Response Spectrum from the same transient event are overlaid. The procedure for response spectrum analysis in midas Gen is outlined below. The procedure for response spectrum analysis in midas Gen is outlined below. the requirements for the degree of. The procedures are illustrated by numerous examples, including coupled lateral-torsional response of. The modification procedure is based on adjusting each spectral value of the given design response spectrum by means of a correction factor, which depends on the structural properties and on the. While almost everyone is aware of what a frequency analysis can do, it is less popular that those extracted eigenmodes can be further processed – and give highly valuable insight into advanced tasks as e. Three dimensional physical and analytical model of the example building Three dimensional physical and analytical model of the example building. DDAM shock spectrum analysis does not require the two stage approach of conventional shock spectrum methods, generation and application. Selection of records for deterministically defined and probabilistically defined earthquakes 3-2. It includes many curricula ("drill sheets"), therapists' notes, and parents' notes, covering (in part) his development from no pretend play. SATISH 1998B4A2437 Under the supervision of Dr. Response Spectrum Analysis gives users the ability to perform seismic analysis based on the building properties: natural periods, eigen-modes, mass system, and user inputs: load function and load direction. This can be the case, for instance, when different kinds of vibration are compared. In this example the density of the beam is 1 kg/m^3. Review of Indian seismic code, IS 1893 (Part 1) : 2002 The Indian seismic code IS 1893 has now been split into a number of parts and the first part containing general provisions and those pertaining to buildings has been released in 2002. Smoothing is a form of low-pass filtering, reducing the high-frequency components of a signal. List the steps in the Nonlinear Response History Analysis method. Response Spectrum Creating the plots in a response spectrum often includes subjecting an oscillating device with known spring, mass and damping to the transient loads. The SRS is defined. 476 Introduction to Structural Dynamic Systems. If you are scaling the response spectrum to match with the static analysis results, you need to input the computed scale factor and specified it under response spectrum cases in ETABS. A modal analysis of the structure is carried out to obtain mode shapes, frequencies & modal participation factors. Tuning and equipment-structure interaction are included. It will also be highly useful if you’re involved in auditing, reviewing or approving vibration analysis tasks, no matter your level of experience. Response Spectrum Analysis 6 Nine-Story Ten-Bay Plane Frame, Eigenvalue Analysis 7 Seven-Story Plane Frame, Gravity and Lateral Loads Analysis 8 Two-Story Three-Dimensional Frame, Dynamic Response Spectrum Analysis 9 Two-Story Three-Dimensional Unsymmetrical Building Frame, Dynamic Response Spectrum Analysis. Output : Figure 3 shows the lower- half of the earthquake acceleration response spectrum that we will use for the analysis. I like to think of a response spectrum analysis as a quick-and-dirty way to get a (hopefully) conservative estimate of the peak response of a system to a transient event without going to the trouble of doing a transient analysis. 5% damping. Lukas Moschena,, Christoph Adama, Dimitrios Vamvatsikosb. Sample Response to Revision Request. Once a spectrum is computed, it can be used for the dynamic response analysis of an NX Nastran model of the component. This paper has em-braced the same for all cases. Pure sinusoidal vibration, on the other hand, can be dealt with using time domain methods. Right: Vertical displacement as determined by the response spectrum analysis. time-dependent strong motion response spectra • Expanded floating point data representations within ORB packets and Datascope waveform files • Pf ORB packets to represent time continuous strong motion response spectra • Provides a very fast method for computing continuous time-dependent response spectra for large numbers of channels. Design response spectrum required for the analysis to be used? Site Class F? Perform ground motion hazard analysis (Sec. EUROCODE 8 – PART 2. SATYENDRA P. Now, engineers are left with 2 choices. midas Civil software is used for structural analyses of the bridge including response spectrum analysis, eigen value analysis, large displacement analysis, vehicle load analysis. - Here Finite Element Approach isused to analyze the dam. These spectra are known as relative velocity and total acceleration response spectra, and are different from the pseudo velocity and pseudo acceleration spectra S v and S a. One other check is to look at file. ) [Accepted 5/3/2017] The following features have not yet proven satisfactory to the Department and shall not be used:. Instructional Material Complementing FEMA 451, Design Examples Seismic Load Analysis 9 - 91. }, abstractNote = {The Technical Committee for Piping Systems of the Pressure Vessel Research Committee (PVRC) has recommended new damping values to be used in the seismic analyses of piping systems in. The computer on our GC-MS has a library of spectra that can be used to identify an unknown chemical in the sample mixture. NUMERICAL EXAMPLE. The response spectrum of an earthquake is the most favored seismic input for earthquake engineers. 6 and seismically isolated or with damping system? Determine design response spectrum (Sec. The response spectrum analysis method is best suited for designing strucutures. Example of actual response spectra of an earthquake with 5% dumping ratio. The vibration response spectrum has many uses. Examples of such events are earthquakes and shocks. At present, there are fewer researches on this type of bridge so it is necessary to do some researches on the seismic response analysis of this bridge. In NX Nastran, use: SOL 109 to perform direct transient response analysis. Using the acceleration response spectrum, an equivalent static load is derived which will provide the same maximum response as that obtained in each. Spectral Analysis; 5. max°,c is the pseudo-velocity spectrum and a plot of Yi,max c2 is the pset acceleration spectrum. We are experienced engineers with advanced degrees and a passion for software development. smooth response spectra, analogous to the RG 1. Shock spectra. - Dynamic Analysis procedures • Scaling of Results of Dynamic Analysis • Response Spectrum Analysis per 1997 UBC • Response Spectrum Analysis Example Registration fee of AED 750 includes the seminar workbook and a metricated copy of the book ‘Seismic Design using Structural Dynamics (1997 UBC)’ By Dr S. • Acceleration response spectrum is shown to the right. This function generates elastic response specra including Displacement Spectrum, Pseudo Acceleration Spectrum, and Pseudo Velocity Spectrum which are needed in a "Response Spectrum Analysis" of structures. 1 BASIS OFEARTHQUAKE GROUND MOTION MAPS. target response spectrum that links nonlinear dynamic analysis back to probabilistic seismic hazard analysis for ground motion selection. 20 Displacement response spectrum of the rotating machine for the rotor-structure-isolator and rotor-structure-FB models. A clear and complete statement. The computer on our GC-MS has a library of spectra that can be used to identify an unknown chemical in the sample mixture. In general, the response spectra analysis procedure is based on the assumption that the dynamic response of a structural model can be approximated as a summation of the responses of the independent dynamic modes of the model. Seismic analysis -Modal spectral analysis It defines the seismic behavior of the structure as the superposition of n‐modes of vibration. Spectrum (SRS) analysis is, by definition, the maximum response of a series of Single Degree Of Freedom (SDOF) systems of same damping to a given transient signal. 8 (107 ratings) Course Ratings are calculated from individual students’ ratings and a variety of other signals, like age of rating and reliability, to ensure that they reflect course quality fairly and accurately. The SRS is defined. Statistical description of random functions; 3. bSchool of Civil Engineering, National Technical University of Athens, Greece. Provides detailed reference material for using SAS/ETS software and guides you through the analysis and forecasting of features such as univariate and multivariate time series, cross-sectional time series, seasonal adjustments, multiequational nonlinear models, discrete choice models, limited dependent variable models, portfolio analysis, and generation of financial reports, with introductory. target response spectrum that links nonlinear dynamic analysis back to probabilistic seismic hazard analysis for ground motion selection. Adding a static load in a RS analysis doesn't make sense for me as the Response spectrum analysis is a dynamic analysis… or are you talking about pre-stressing a structure before doing the RS analysis (there's probably a way to do that too)?. Apply non-seismic loads to unstressed structure Select pushover direction and mode shape for seismic sign to update stiffness 𝑅=1. V8i Download File. Response analysis in general is a method to characterize a vibration or shock when other frequency analysis methods are inadequate. These pseudo-velocity and acceleration spectra are of the same physical interest but not an essential part of a response spectrum analysis. CQC or GMC (Gupta) method • Combination of three ETABS direction by ABS or SRSS method. OnlineCivilDigital 78,150 views. While almost everyone is aware of what a frequency analysis can do, it is less popular that those extracted eigenmodes can be further processed – and give highly valuable insight into advanced tasks as e. Save the model and perform the analysis through Layout window > File > Analyze. The ZPA method considers the masses in the supports. If you are scaling the response spectrum to match with the static analysis results, you need to input the computed scale factor and specified it under response spectrum cases in ETABS. Dynamic Analysis of Linear MDOF Systems : Introduction, modal analysis - Response-history for earthquake excitations using modal analysis - Response spectrum analysis for peak responses - Concept of Caughey damping as a general type of proportional damping. Modeling and analysis of the design example 25 2. and Stiady, James L. Re: Seismic response spectrum What you can download from www. Three dimensional physical and analytical model of the example building Three dimensional physical and analytical model of the example building. Iglesia, Geraldo R. Acceleration Response Spectrum Curves Soil-Structure Interaction Analysis for Bridge. Analysis of Dynamic Response by Mode Superposition 4. This tutorial will illustrate how to set up a model for a response spectrum analysis in ETABS however before we do this let's discuss what a response spectrum analysis is response spectrum analyses are typically used for performing seismic analysis response spectrum analysis calculates the maximum response values in each mode of the structure from a spectrum curve and then combines these. Related to Analysis/Design: • Modal Response Spectrum Analysis (Malley) * • Nonlinear Response History Analysis (Haselton) • Diaphragm Analysis and Design (Ghosh) • Rigid Wall/Flexible Diaphragm Buildings (Kelly) • Strength-Based Foundation Design (Johnson) • Foundations on Liquefiable Sites (Bachman). Order Analysis. Historically, the shock-response spectrum was initially used to describe transient phenomena, at the time called shocks. Draft 6 Steps 4 to 6 are performed as an iterative response spectrum analysis process. In such areas, the normally employed used procedure is response spectrum analysis method (ASCE 7-05 Section 162) which is also acceptable by IBC. EERI, and Jack W. Re: Seismic response spectrum What you can download from www. Response Spectra Analysis using ETABS. ) and then issue a PFACT command for that condition. 7, IBC Section 1618) (f) Nonlinear response history analysis ((ASCE 7 Section 9. CAEPIPE will apply these loads to compute the response of the piping system by performing a Response Spectrum analysis along with other load cases defined in the piping system. Order Tracking Analysis. Design Acceleration The elastic design response spectrum used in the analyses is consistent with that recommended by ATC-40 (1996). The response spectrum is a plot of the maximum response, as a function of oscillator frequency of an array of Single Degree of Freedom,. – accounting for mode coupling makes the response estimate from these methods more realistic and closer to the exact time history solution Response Spectrum. This is commonly referred to as the equivalent-linear analysis method, which was first used in the computer program SHAKE (Schnabel et al. 12 in/s 2 For T2 = 0. and Chopra A. Shock Response Spectrum Analysis Introduction. dynamic analysis can be performed by response spectrum method. Describe the analysis process and requirements for the Equivalent Lateral Force, the Modal Response Spectrum, Linear Response History, and Nonlinear Response History Analysis methods. I went through the online help but I don't get it how exactly it is determined. 806 or the appropriate value of acceleration due to gravity in the current unit system. Review of Indian seismic code, IS 1893 (Part 1) : 2002 The Indian seismic code IS 1893 has now been split into a number of parts and the first part containing general provisions and those pertaining to buildings has been released in 2002. Three different floor plans that are symmetric (SB), monosymmetric (MB), and unsymmetric (UB) with torsional irregularity are taken as sample buildings. Load Case Name edit box. The component name corresponding to the group of excited nodes. An equivalent linear response spectrum approach is proposed for nonlinear surface ground analysis. SOLIDWORKS Simulation Dynamics. Are you an ASCE Member? We recommend that you register using the same email address you use to maintain your ASCE Member account. Vibration analysis is a huge topic and is easily the second most common type of FEA analysis after basic static stress analysis. The parameters S DS and S D1 are used to calculate the design response spectrum in Section 11. Now, for a response spectrum analysis is SW (or any FEA package), you're input is a response spectrum curve. A sample psd curve is shown below. EXAMPLE OF APPLIED BEHAVIOR ANALYSIS-PRETEND PLAY. A Computationally Efficient Ground-Motion Selection Algorithm for Matching a Target Response Spectrum Mean and Variance Nirmal Jayaram,a) Ting Lin,a) M. CE543 - Structural Dynamics Syllabus for CE 543 Spring 2017 Text: Structural Dynamics, Theory and Application by Tedesco, McDougal and Ross, published by Addison-Wesley, 1999. Modeling and analysis of the design example 25 2. In a spectral response solution, the peak accelerations at different frequencies are specified instead of a power density. Tuning and equipment-structure interaction are included. Three different floor plans that are symmetric (SB), monosymmetric (MB), and unsymmetric (UB) with torsional irregularity are taken as sample buildings. Normal distribution and Correlation; 4. response spectrum, for example, gives in effect a harmonic analysis of the earth- quake ground motions, and serves the same purpose in defining significant period content as would the related Fourier spectrum. For example, the term 'response spectrum' normally is used to a plot of maximum response parameters as a function of frequency or period, a given excitation of the base of a single-degree-of-freedom damped oscillator, for acceleration time history of excitation associated with a specific earthquake. seismic analysis of multistorey building. Since our start in 1994, IES engineers have helped thousands of people, just like you, with innovative structural analysis and design tools. 5% damping. This tutorial will illustrate how to set up a model for a response spectrum analysis in ETABS however before we do this let's discuss what a response spectrum analysis is response spectrum analyses are typically used for performing seismic analysis response spectrum analysis calculates the maximum response values in each mode of the structure from a spectrum curve and then combines these. Audio Spectrum Analyzer has variable displays, Fast Fourier Transform (FFT) display, variable sample rates (8000 Hz, 11025 Hz, 22050 Hz, and 44100 Hz), variable transform sizes (1k, 2k, 4k, and 8k. Basarab Viaduct Bridge Bucharest, Romania C&T Engineering Srl. This thesis evaluates the application of a simplified analysis procedure as implemented in version 16 of CSiBridgeTM for design of bridges crossing earthquake fault ruptures. Seismic response spectra for elastic design. Response spectra can also be used in assessing the response of linear systems with multiple modes of oscillation (multi-degree of freedom systems), although they are only accurate for low levels of damping. Discuss the differences between response spectrum and response history analysis in determining seismic forces. Modal Response Spectrum Analysis (MRSA) is one of the most commonly used methods for determination of seismic response in building structures. presents the dynamic time history analysis and response spectrum method of a concrete gravity dam by using STAADPRO. In this study we focus on. Note: If a modal analysis case has not yet been defined, first define the modal analysis case and then define the response-spectrum case. Results of a static and dynamic analysis are combined. The transfer function should be obtained in eight directions, and you should have an 8 folders, as in Figure 8. purposes of design checks. The acceleration response spectra is represented as piecewise linear segments, whose end-points are defined by a (time, acceleration) coordinate. EXAMPLE CALCULATION - Seismic Actions to BC3: 2013 Page 8 of 22 • Rz,i (MT,i = 1 ) is the rotation of the storey i about the vertical axis due to a unit moment, MT, applied at the centre of stiffness. cepstrum analysis to modal analysis of mechanical structures. The Seismic analysis used horizontal input. Now, engineers are left with 2 choices. Interpreting Survey Results After you have collected an adequate number of responses to your survey, it's finally time to take a look at the data to see what they say. Vibration analysis is a huge topic and is easily the second most common type of FEA analysis after basic static stress analysis. response of structure due to input spectrum. 5 Hz, 3 Hz, 5 Hz and 10 Hz and 5% damping ratio. the codified response spectrum enveloping criteria (e. building as shown below is required to be designed for a design earthquake with PGA=0. Dynamic analysis (Response Spectrum) is performed for a steel structure.