Singlepoint response spectrum a single response spectrum excites all specified points in the model. The absolute acceleration response spectrum for 5% damping plotted together. Supports many generation techniques including linear and exponential chirp, wavesyn, burst random, linear and exponential chirp on burst random, enveloped random, burst sine, or iterate from user waveform. A new opensource software for strong ground motion data processing. This paper presents an algorithm for generation of acceleration spectrum compatible time history, which requires target response spectra for the site and. A response spectrum is used to provide the most descriptive representation of. Eurocode 8 design acceleration response spectrum for design of ductile structures in the inelastic range with the behavior factor q description. The user can change the input parameters to construct a sitespecific response spectrum considering different hazard conditions. A plot of the peak value of a response quantity eg. The response spectrum spectra is plural is a conventional representation of the maximum response displacement, velocity or acceleration of an infinite series of simple damped single degree of freedom sdof harmonic oscillators to the seismic signal. Construction of design response spectrum the chilean way eps 256. The vibration response spectrum is particularly suited for random vibration inputs. The acceleration history base motion is not given directly in a response spectrum analysis. Spectral acceleration, velocity and displacement spectra.
I would like to know what is a velocity response spectrum, pseduovelocity response spectrum, and how they are different from one another. Scale factor for is 1893 indian code etabs computers and. Openseismomatlab file exchange matlab central mathworks. 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. Elastic response spectrum file exchange matlab central. The shape of the response spectrum is greatly influenced by. A response spectrum can be defined according to ascesei 710 by selecting ibc as input type. Conversion of earthquake acceleration data to pseudo. Geological survey editorial standards or with the north american stratigraphic code. Derivation of ibc design maps the ground motions for design that are mapped in the ibc are based on, but not identical to, the usgs probabilistic seismic hazard analysis psha maps for 2% in 50 years probability of exceedance 0. The shock response spectrum is a calculated function based on the acceleration time history. The sa at different frequencies may be plotted to form a response spectrum.
The peak ground acceleration, duration, and frequency content of earthquake can be obtained from an accelerograms. The result is the artificial acceleration time history for a site in sleman district, yogyakarta, indonesia. The mcer spectral response acceleration parameters adjusted for site class effects are sms fa ss 1. For response spectrum analysis the typical load excitation is acceleration vs. The parameters for calculating the acceleration response spectra include the site latitude and longitude, expressed in decimal degrees. Software confidential shock spectrum analysis what is response shock spectra what is the difference between harmonic and shock spectrum input how to create shock spectra from acceleration transient input how to analyze structure subjected to shock input various methods to combine modal response. Srs package adds shock response spectrum srs plots to shock and transient capture test modes. Seismic hazard curves and uniform hazard response spectra for the united states by a. Sep 21, 2017 it determines the response spectrum of accelerations, pseudoaccelerations, displacements, velocities and pseudovelocities, for an accelerogram, by means of matlab program with input file in. Ansys mechanical workbench supports response spectrum analysis. Applicable for the design of ductile structures where the inelastic behavior is taken into account explicitly with the behavior factor q. Design example 1 design spectral response acceleration parameters 11.
Software to download usgs earthquake hazard program. Portland state university acceleration response spectra. Calculation of the design response spectrum in terms of spectral acceleration representing the seismic action in the horizontal or vertical direction. Depending on the results requested in analysis settings for a response spectrum solution, velocity and acceleration results can be obtained, in addition to deflection, stress and strain. Oct 12, 2019 the function generates pseudospectral acceleration psa, pseudospectral velocity psv and spectral displacement sd spectra for given damping ratio e. Response spectrum analysis by using etabs software youtube. Response spectrum is defined as the response to a given acceleration acting at a set of massdamperspring oscillators, which are adjusted to the different resonant frequencies while their resonance gains qfactor are equal to the same value. The design response spectrum can be seen as an envelope over all known and anticipated earthquakes in a certain geographical region. The representation of maximum response of idealized single degree freedom system having certain period and damping, during earthqua. Larsa is privately owned and based in new york, with all its software development and product support.
Calculation of shock response spectrum jiri tuma1 and petr koci2 abstract. Development of sitespecific response spectra for seismic analysis of concrete hydraulic structures section i introduction 31. The first data reported from an earthquake record is generally the peak ground acceleration pga which expresses the tip of the maximum spike of the acceleration ground motion figure 1. The software system receives the acceleration data from a lower computer, then processes the data and uses fft and shock response spectrum srs to judge shock test result. Srs package adds shock response spectrum srs plots to shock and transient capture. In order to be able to use a response spectrum for analysis of an event that has not yet happened, a design response spectrum is created. This function gives the rootmeansquare response of each system to an acceleration base input. The pipeline is divided into individual spans or a series of segments. Versus natural frequency f hz of narrowband response spectrum according to en 19981 1 figure 02 activation of zpa analysis in dynam pro forced vibrations.
The formula for design spectral response acceleration with 5% dampness is, and that for 1second period is. Conversion of earthquake acceleration data to pseudo acceleration and spectral acceleration. Definition of design spectral response acceleration. The main features of the program include modification of earthquake. The spectrum ordinates defined within various code options, including is. Earthquake hazard map showing peak ground accelerations having a 2 percent probability of being exceeded in 50 years, for a firm rock site. Response spectrum analysis definition comsol multiphysics. Values are percentages of gravitational acceleration. Spectral acceleration, with a value related to the natural frequency of vibration of the building, is used in earthquake engineering and gives a closer approximation to the motion of a building or other structure in an earthquake than the peak ground acceleration value, although there is normally a correlation between short period sa and pga.
Graphs can be easily autoscaled or zoomed, and cursors displayed. Either singlepoint or multipoint response spectrum analysis can be performed. A shock response spectrum srs is a graphical presentation of a transient acceleration pulses potential to damage a structure. Vibration meter data logger vibration analysis equipment. Lets assume the excitation angle 0 and building principle direction is u1 so i will apply response spectrum function per ibc 2006 in u1 direction by a scale factor. Response spectra are used in seismic design, for example, according to. Each linear elastic response spectrum is associated with a fixed damping ratio.
Response spectrum analysis massachusetts institute of. Sample acceleration time history from pyrotechnic shock event. Acceleration, velocity and displacement spectra arithmetic. An answer or a reaction to this vibration can be acceleration, a velocity or displacement. The acceleration time history and response spectra design for certain site can be acquired using the seismic hazard analysis, amplification of ground motion quantity, and spectral matching in time domain. Scale factor for is 1893 indian code etabs computers. Constant ductility inelastic acceleration response spectrum. Response spectrum analysis is a method for estimating structural.
Ground motions for design usgs earthquake hazard program. Static seismic loads are considered to be in direct proportion to the weight of pipe segments. The design response spectrum provides a general procedure to estimate the expected dynamic load on. Earthquake spectral response accelerations shall be taken as the spectral response accelerations represented by a 5 percent damped acceleration response spectrum having a 2 percent probability of exceedance within a 50yr. Constant ductility inelastic velocity response spectrum. Rspmatch software developed by abrahamson 1992 list of candidate earthquake records used for rspmatch. The peak ground acceleration pga and sa values at ground surface may vary signi. When defining response spectrum load case in etabs, we have three directions. The spectrum must be converted to the specific set of units used throughout the model by applying a scale factor given as the value of gravity acceleration in the. An accelerogram can be integrated to obtain the time variations of the ground velocity and ground displacement. A free tool to generate curves for aashto lrfd bridge design specifications 2007 and aashto guide specification for lrfd seismic bridge design 2009 for locations in the continental united states. Design example 1 design spectral response acceleration.
My question is why we dont apply u2 and u3 in the same load case. The shock response spectrum is the peak absolute acceleration response of each sdof system to the time history base input. Response spectrum generator according to ascesei 710 ibc. This file can be used as input file to the qsrs and arbit programs. The seismic static coefficients are usually obtained from the seismic zone, which corresponds to a level of seismic acceleration. The standard response spectrum for medium soil type and that can be given. To solve the equation of motions for different periods, the newmark linear method was used.
Apr 09, 2016 a velocity response spectrum is a graph of velocity versus period. The absolute acceleration response spectrum for 5% damping plotted together with the corresponding pseudoacceleration spectrum. It applies an acceleration time history as an excitation to an array of singledegreeoffreedom sdof systems. In the present study, the response spectrum analysis rsa of regular rc building frames is compare with response. The peak acceleration from the response spectrum is applied as a lateral force distributed along the pipe, and bending stresses and support reactions are calculated. A response spectrum is used to provide the most descriptive representation of the influence of a given earthquake on a structure or machine. It makes use of the nice fact, that the acceleration response of a onemassspringdamper system with base excitation does not depend on the mass, but only on eigenfrequency and damping. These parameters used to make response spectra tool, which can analyze the performance of the structures with the effect of earthquake. The typical earthquake ground motion response spectrum represents an envelope of the peak responses of many singledegreeoffreedom sdof systems with different periods. Dear stefano, frequency is the inverse of the period, f1t, simply use excel and you are done. Nuclear power plant buildings and components, for seismic loading airborne electronic equipment for shock loading commercial buildings in earthquake zones types of response spectrum analysis. Estimation of peak ground acceleration and spectral. Software for generation of spectrum compatible time history.
Construction of design response spectrum the chilean way. The earthquake ground motion and response spectra design. It determines the response spectrum of accelerations, pseudoaccelerations, displacements, velocities and pseudovelocities, for an accelerogram, by means of matlab program with input file in. This function generates elastic response spectrum for seismic design of buildings and bridges. Response spectrum curve generator for bridge design. The vibration meter data logger vibration sentry e16g is an all digital design with an integrated oscilloscope function that can show the vibration signals in real time, and an integrated spectral analyzer function that shows a 512line spectrum in real time. The map is based on the most recent usgs models for the conterminous u. Could you also do the same for acceleration and pseduoacceleration. Response spectrum analysis in etabs software issues. An introduction to the vibration response spectrum revision d. Larsa 4d web tools response spectrum curve generator for bridge design. Ansys apdl commands objects after response spectrum analysis.
The linear elastic response spectrum leresp for a response quantity acceleration, velocity, displacement, etc. The absolute acceleration has a maximum at frequencies similar to the frequency content of the input signal. Oct 29, 2018 the standard response spectra for type of soil considered is applied to building for the analysis in etabs 20 software. Shock response spectrum srs vibration control software. To scale the input of ground motion records, what software we can use. Shock response spectrum srs analysis crystal instruments. The function generates pseudospectral acceleration psa, pseudospectral velocity psv and spectral displacement sd spectra for given damping ratio e. The resulting plot can then be used to pick off the response of any linear system, given its natural frequency of oscillation. Chapter 3 development of sitespecific response spectra. Calculation of acceleration, velocity, and displacement response. A response spectrum is a plot of the peak or steadystate response displacement, velocity or acceleration of a series of oscillators of varying natural frequency, that are forced into motion by the same base vibration or shock.
Earthquake software for response spectrum matching. Mass distribution, resulting frequencies and effective modal masses. Selection, scaling and simulation of input ground motion. Zpa method in response spectrum analysis dlubal software.
Spectral ordinates are for linearelastic singledegreeoffreedom system with unit mass. As it is stated in the iso 184314 standard, a shock response spectrum is defined as the response to a given acceleration acting at a set of massdamperspring oscillators, which are adjusted to. The parameter vs30 describess the average shear wave velocity between 0m and 30m depth, which describes the site soil conditions. The input file would typically be the users measured accelerometer data. Data and text annotations can be easily placed on the graphs, with data values updated live as the data changes. The values of the spectrum are generated between a maximum period of 4 seconds 0. Spectral acceleration, with a value related to the natural frequency of vibration of the building, is used in earthquake engineering and gives a closer approximation to the motion of a building or other structure in an earthquake than the peak ground acceleration value. Seismic analysis of high rise building with is code 18932002 and is code 18932016 narayan malviya1. But that velocity is the maximum velocity that the structureor system will reach for each period. Returning to the main objective, the translation between acceleration, velocity and displacement spectra, we can see a possible form of relationship between acceleration and velocity merely by looking at the units. Open source software for strong ground motion data processing. Specifying a spectrum the response spectrum method is based on first finding the peak response to each base motion excitation of a one degree of freedom system that has a natural frequency equal to the. Rootmeansquare rms of acceleration, velocity and displacement. Is there any software for scaling earthquake records.
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