This function generates elastic response spectrum for seismic design of buildings and bridges. It determines the response spectrum of accelerations, pseudoaccelerations, displacements, velocities and pseudovelocities, for an accelerogram, by means of matlab program with input file in. Portland state university acceleration response spectra. Graphs can be easily autoscaled or zoomed, and cursors displayed. Response spectrum analysis in etabs software issues. Response spectrum generator according to ascesei 710 ibc. It plots the peak acceleration responses of a bank of single degreeoffreedom sdof spring, mass damper systems all experiencing the same baseexcitation as if on a rigid massless. 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. The result is the artificial acceleration time history for a site in sleman district, yogyakarta, indonesia. The standard response spectrum for medium soil type and that can be given.
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. 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. Conversion of earthquake acceleration data to pseudo acceleration and spectral acceleration. Response spectrum analysis massachusetts institute of.
Ansys apdl commands objects after response spectrum analysis. Software for generation of spectrum compatible time history. 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. Ground motions for design usgs earthquake hazard program. Design example 1 design spectral response acceleration. Acceleration, velocity and displacement spectra arithmetic. Rootmeansquare rms of acceleration, velocity and displacement. Shock response spectrum srs vibration control software. 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 the influence of a given earthquake on a structure or machine. 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. It applies an acceleration time history as an excitation to an array of singledegreeoffreedom sdof systems. For response spectrum analysis the typical load excitation is acceleration vs. Development of sitespecific response spectra for seismic analysis of concrete hydraulic structures section i introduction 31.
Chapter 3 development of sitespecific response spectra. The shock response spectrum is the peak absolute acceleration response of each sdof system to the time history base input. Constant ductility inelastic velocity response spectrum. Construction of design response spectrum the chilean way. Vibration meter data logger vibration analysis equipment. A shock response spectrum srs is a graphical presentation of a transient acceleration pulses potential to damage a structure. Data and text annotations can be easily placed on the graphs, with data values updated live as the data changes. Response spectrum analysis by using etabs software youtube. The acceleration history base motion is not given directly in a response spectrum analysis. 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.
Static seismic loads are considered to be in direct proportion to the weight of pipe segments. The typical earthquake ground motion response spectrum represents an envelope of the peak responses of many singledegreeoffreedom sdof systems with different periods. The acceleration response spectrum of a ground motion is a relationship between the natural period of vibration of a sdof system and the maximum absolute acceleration that it experiences under the ground motion. Calculation of acceleration, velocity, and displacement response. It is selfcalibrated using the earths gravity as a reference. 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. Either singlepoint or multipoint response spectrum analysis can be performed. Larsa 4d web tools response spectrum curve generator for bridge design. Openseismomatlab file exchange matlab central mathworks. In the present study, the response spectrum analysis rsa of regular rc building frames is compare with response. To solve the equation of motions for different periods, the newmark linear method was used. 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. 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. Larsa is privately owned and based in new york, with all its software development and product support.
The absolute acceleration response spectrum for 5% damping plotted together with the corresponding pseudoacceleration spectrum. Construction of design response spectrum the chilean way eps 256. The pipeline is divided into individual spans or a series of segments. An introduction to the vibration response spectrum revision d. A shock response spectrum is a useful tool for estimating the damage potential of a shock pulse, as well as for test level specification. The design response spectrum provides a general procedure to estimate the expected dynamic load on.
The earthquake ground motion and response spectra design. The main features of the program include modification of earthquake. Values are percentages of gravitational acceleration. 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. The values of the spectrum are generated between a maximum period of 4 seconds 0. Definition of design spectral response acceleration.
The peak ground acceleration, duration, and frequency content of earthquake can be obtained from an accelerograms. 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. The resulting plot can then be used to pick off the response of any linear system, given its natural frequency of oscillation. The map is based on the most recent usgs models for the conterminous u. Open source software for strong ground motion data processing. The seismic static coefficients are usually obtained from the seismic zone, which corresponds to a level of seismic acceleration. Sample acceleration time history from pyrotechnic shock event. 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. 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 response spectrum is used to provide the most descriptive representation of. Is there any software for scaling earthquake records. Design example 1 design spectral response acceleration parameters 11. 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. This function gives the rootmeansquare response of each system to an acceleration base input.
Singlepoint response spectrum a single response spectrum excites all specified points in the model. The shock response spectrum is a calculated function based on the acceleration time history. Seismic hazard curves and uniform hazard response spectra for the united states by a. 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. Shock response spectrum of an arbitrary acceleration time history. Srs package adds shock response spectrum srs plots to shock and transient capture. The spectrum ordinates defined within various code options, including is. But that velocity is the maximum velocity that the structureor system will reach for each period. Elastic response spectrum file exchange matlab central. This file can be used as input file to the qsrs and arbit programs. Constant ductility inelastic acceleration response spectrum. The function generates pseudospectral acceleration psa, pseudospectral velocity psv and spectral displacement sd spectra for given damping ratio e.
Software to download usgs earthquake hazard program. Dear stefano, frequency is the inverse of the period, f1t, simply use excel and you are done. The user can change the input parameters to construct a sitespecific response spectrum considering different hazard conditions. A new opensource software for strong ground motion data processing. Shock response spectrum srs analysis crystal instruments. The absolute acceleration has a maximum at frequencies similar to the frequency content of the input signal. I would like to know what is a velocity response spectrum, pseduovelocity response spectrum, and how they are different from one another. Earthquake hazard map showing peak ground accelerations having a 2 percent probability of being exceeded in 50 years, for a firm rock site. The absolute acceleration response spectrum for 5% damping plotted together. Estimation of peak ground acceleration and spectral. These parameters used to make response spectra tool, which can analyze the performance of the structures with the effect of earthquake. An accelerogram can be integrated to obtain the time variations of the ground velocity and ground displacement. The representation of maximum response of idealized single degree freedom system having certain period and damping, during earthqua. 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.
Response spectrum curve generator for bridge design. Seismic analysis of high rise building with is code 18932002 and is code 18932016 narayan malviya1. Spectral acceleration, velocity and displacement spectra. The vibration response spectrum is particularly suited for random vibration inputs. The input file would typically be the users measured accelerometer data. Oct 29, 2018 the standard response spectra for type of soil considered is applied to building for the analysis in etabs 20 software. Calculation of shock response spectrum jiri tuma1 and petr koci2 abstract.
The formula for design spectral response acceleration with 5% dampness is, and that for 1second period is. The sa at different frequencies may be plotted to form a response spectrum. Conversion of earthquake acceleration data to pseudo. 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 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 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.
To scale the input of ground motion records, what software we can use. Applicable for the design of ductile structures where the inelastic behavior is taken into account explicitly with the behavior factor q. Response spectrum analysis is a method for estimating structural. The peak ground acceleration pga and sa values at ground surface may vary signi. 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. Mass distribution, resulting frequencies and effective modal masses. My question is why we dont apply u2 and u3 in the same load case. 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. The mcer spectral response acceleration parameters adjusted for site class effects are sms fa ss 1. 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. Response spectrum analysis definition comsol multiphysics. Geological survey editorial standards or with the north american stratigraphic code. Each linear elastic response spectrum is associated with a fixed damping ratio.
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. 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. The design response spectrum can be seen as an envelope over all known and anticipated earthquakes in a certain geographical region. A plot of the peak value of a response quantity eg. Rspmatch software developed by abrahamson 1992 list of candidate earthquake records used for rspmatch. Oct 12, 2019 the function generates pseudospectral acceleration psa, pseudospectral velocity psv and spectral displacement sd spectra for given damping ratio e.
Apr 09, 2016 a velocity response spectrum is a graph of velocity versus period. An answer or a reaction to this vibration can be acceleration, a velocity or displacement. 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. Could you also do the same for acceleration and pseduoacceleration. Scale factor for is 1893 indian code etabs computers. Selection, scaling and simulation of input ground motion. Scale factor for is 1893 indian code etabs computers and. Response spectra are used in seismic design, for example, according to. The parameters for calculating the acceleration response spectra include the site latitude and longitude, expressed in decimal degrees. 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.
Earthquake software for response spectrum matching. 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. Eurocode 8 design acceleration response spectrum for design of ductile structures in the inelastic range with the behavior factor q description. Ansys mechanical workbench supports response spectrum analysis. Zpa method in response spectrum analysis dlubal software. Calculation of the design response spectrum in terms of spectral acceleration representing the seismic action in the horizontal or vertical direction. The parameter vs30 describess the average shear wave velocity between 0m and 30m depth, which describes the site soil conditions.