The response spectral ratios shown in figure 39 have been adopted into the nehrp provisions bssc 1994 and the uniform building code international conference of building officials 1997. Comparative study of static and dynamic seismic analysis. Response spectra using duhamels integral in the above examples, the input force is simple and hence a closed form solution has been obtained for the response spectrum. Construction of design response spectrum the chilean way. Vibrationdata programs to calculate shock response spectrum. Furthermore, a single earthquake record has a particular frequency content which. Response spectrum versus design spectrum consider the acceleration response spectrum notice the region of red circle marked. The earthquake loading is assumed to be described in terms of response spectra.
Modal response spectrum method means a method of dynamic analysis in which a given earthquake design spectrum is applied to a mathematical model of the structure and the response. Save the model and perform the analysis through layout window file analyze. Response spectrum is a plot of the peak or steadystate response displacement, velocity or. An elastic response spectrum characterizes the maximum response of structures with a certain amount of internal damping to earthquake loading at a specific. Sgs s eismic data g eneration s ystem extracts and plots graphs of earthquake history records, seismic response spectrums and design response spectrums using the midas family programs builtin earthquake databasebuiltin earthquake history records about 30 earthquake records in north america from 1940 until 1990. The representation of the maximum response of idealized single degree freedom system having certain period and damping, during earthquake ground motions. Relief loads and water hammerslug flow spectra analysis. Response spectrum of any earthquake ground motion is simply a plot of the maximum response during that earthquake of a single degree of freedom sdf system as a function of its natural vibration period t n or frequency w n or f n, for a. Earthquake response spectrum analysis of 4 story shear. Seismic response spectrum gui file exchange matlab central.
Elastic response spectrum file exchange matlab central. A new response spectrum method is developed for seismic analysis of linear. Mar 11, 2017 a response spectrum analysis calculates the maximum response of a structure to transient loads such as displacement,velocity or acceleration, that are forced into vibration by a base vibration or shock. Practical guidelines to select and scale earthquake. Earthquake hazard map showing peak ground accelerations having a 2 percent probability of being exceeded in 50 years, for a firm rock site. This spectrum were done taking as a start point normalized version of the response spectra obtained from different accelerograms recorded for the following earthquakes. Pdf origin of the response spectrum method researchgate. A displacement response spectrum is the plot of maximum displacement of a single degree of freedom system sdof to a particular ground motion as a function of the natural frequency and damping ratio of the sdof.
Response spectrum method is the linear dynamic analysis method. Response spectrum method in seismic analysis and design of. Low seismicity type 2 spectra are recommended when the earthquakes that contribute most to the seismic hazard have a surfacewave magnitude, m s, not greater than 5. Thus, if you can find out the natural frequency of the structure, then the peak response of the building can be estimated by. Pdf the earthquake ground motion and response spectra. We have examined the data for peak horizontal acceleration, velocity, and response spectra and do not find support for a magnitudedependent shape refs. Comparison between different shapes of structure by. Seismic analysis of retaining walls, buried structures, embankments, and integral abutments fhwanj2005002 601 unclassified unclassified nchrp 1249, integral abutments, response. Laboratory for earthquake engineering, national technical. Seismic analysis method the maximum displacement of the sdof system having. Response spectrum method of analysis mechanical engineering. Response spectrum analysis midas civil dynamic analysis purpose of rs analysis. Modelling of earthquake response spectra for strike slip. Dynamic analysis uses the units from the piping input file or from the configuration file of a structuralonly analysis.
An accelerogram can be integrated to obtain the time variations of the ground velocity and ground displacement. In the case of large multistoried buildings the response at different levels vary due to different factors in dynamic load and lateral load, therefore it is necessary to determine the response at different floors for efficient design. For more information on dynamic load cases, data, and procedures, see external interfaces. A response spectrum is a graphical relationship of. Gupta group leader, civil engineering group birla institute of technology and science pilani, rajasthan333031. The flat hyperbolic x r response spectrum shape is based on observations of moderate and large magnitude. Record selection for nonlinear seismic analysis of structures. Sgs s eismic data g eneration s ystem extracts and plots graphs of earthquake history records, seismic response spectrums and design response spectrums using the midas family programs builtin earthquake database. Seismic analysis of highrise building using response. Geological survey editorial standards and stratigraphic nomenclature. Dynamic analysis of a structure subjected to earthquake excitation using the response spectrum. Sep 16, 2011 the response spectrum of an earthquake is the most favored seismic input for earthquake engineers. The shape of the response spectrum is greatly influenced by the local subsurface conditions. In a response spectrum analysis, the results of a modal analysis are used in terms of a known spectrum to calculate displacements and stresses in the model.
Introduction response spectrum is one of the useful tools of earthquake engineering for analyzing the performance of structures especially in earthquakes, since many systems behave as single degree of freedom systems. Response spectrum and average response spectrum of 12 ground motion records for 5% damping is plotted in figure 5 as well as demand spectrum provided in turkish earthquake code2007 for design earthquake with 10% probability of exceedance in 50 years on z3 soil class compatible to soil class c of fema356. Such spectra are usually provided by the architectengineer or seismic structural analyst of the building. Response spectrum analysis is the dominant contemporary method for dynamic analysis of building structures under seismic loading. The maximum response plotted against of undamped natural period and for various damping.
Introduction to the computation of response spectrum for. To solve the equation of motions for different periods, the newmark linear method was used. Earthquake response spectrum free software download. A study of earthquake response spectra for different. Using these ground motions, influences of the shearwave velocity, earthquake magnitudes, sourcetosite.
Another reason is convenience in generating design response spectra rather than power spectral densities from existing data. 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. Response spectrum method and time history analysis are widely used in the seismic design of buildings. Software to download usgs earthquake hazard program. However, the mostly used ground response spectra, i. Nelson lam and john wilson university of melbourne nelson lam is senior lecturer at the university of melbourne. Newmark design spectra have been implemented in many building codes, especially in building codes for critical structures. Using the information gathered in the preceding input the data into steps, cb the model cy inputs section of the deterministic response spectrum spreadsheet shown below todevelop the deterministic ars for each fault. Figure 3 shows the lower half of the earthquake acceleration response spectrum that we will use for the analysis. Earthquake analysis and design of simple structures and. The earthquake ground motion and response spectra design for.
Floor response spectra generation for seismic design of buildings. The response spectrum model stipulated in the current australian earthquake loading standard as 1170. Earthquake design spectra given a earthquake ground acceleration, there is no difficulty to compute response using newmark s method as the previous example. The accelerograph records three orthogonal components of ground acceleration. Although seismic site response analysis can be performed using readily available computer software, occasionally the person doing such analysis may rely completely on the output. The development procedure for floor response spectra is described in a number of official documents. If the input force is arbitrary, we can find the response spectrum only numerically. Input parameters into deterministic response spectrum spreadsheet. Therefore, we can generate a response spectrum for that earthquake. The earthquake response spectrum is a fundamental quantity in earthquake engineering and in aseismic design of structure and it is one of the key tools applied. The paper extends previous work by the authors on displacement and acceleration spectra for analysis and design of. Pdf this report is the development of response spectrum analysis for mdof structure in matlab.
The peak displacement response of an undamped sdof system subjected to a. Modal analysis is performed to identify the modes, and the response in that mode can be picked from the response spectrum. Tutorial for response spectrum analysis using caepipe. Displacement and acceleration design spectra for seismic isolation systems in christchurch 2014 nzsee conference d. Present code plots the response spectrum for the given seismic input. The sdof response spectrum method usually gives less conservative results than simplified procedures, yet easy to. Records for nonlinear response history analysis of structures by erol kalkan and anil k. The main reasons for the widespread use of this method are. Deformation response spectrum is a plot of the maximum displacement that a sdf structure is experienced during the earthquake as a function of its natural vibration period for a given value of damping. This paper develops a probabilistic methodology for the seismic reliability analysis of structures with random properties. To overcome the above difficulties, earthquake response spectrum is the most popular tool in the seismic analysis of structures.
History of earthquake response spectrum, history of earthquake engineering. Download limit exceeded you have exceeded your daily download allowance. Aside from the development of the response spectrum method, the paper. Response spectra are very useful tools of earthquake engineering for analyzing the performance of structures and equipment in earthquakes, since many behave principally as simple oscillators also known as single degree of freedom systems. If the equipment is located at a higher floor of a building, then the response spectra for the earthquake motion at that floor are used in the analysis. In that method the peak response of structure during an earthquake is obtained directly from the earthquake response, but this is quite accurate for structural design applications duggal, 2010.
Type 1 spectra correspond to typical high seismicity hazard. Timehistory method the sdof response spectrum method can be used as long the structure or equipment can be modeled by a single degree of freedom system consisting of a spring, mass and damping. Hence, it is essential to consider the seismic load for the design of multistoried building. Now, it is necessary to construct the design response spectrum. Response spectra can also be used in assessing the response of linear systems with multiple modes of oscillation multidegree of freedom systems, although they are only accurate for low levels of damping. The software consists of a server and client but also includes data extraction and manipulation tools. Sep 10, 20 the response spectrum method of analysis is developed using the following steps. The user can change the input parameters to construct a sitespecific response spectrum. Development of earthquake energy demand spectra ahmet an. Geological survey editorial standards or with the north american stratigraphic code. Why use spreadsheets for seismic site response analysis.
Nonlinear dynamic analysis it is known as time history analysis. Displacement and acceleration design spectra for seismic. A plot of the peak value of a response quantity eg. Seismic hazard curves and uniform hazard response spectra for the united states by a. Study of earthquake response spectra submitted in partial fulfillment of the requirements of bits c421t. Earthquake analysis with sap2000 response spectrum analysis response spectrum analysis is performed to verify that the column design is adequate. Datta department of civil engineering, iit delhi response spectrum method of analysis 0 5 10 15 20 25 30 0. 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. A limited number of studies have shown that shape and the magnitude of response spectra for stations located on rock deposits are different from those located on.
Brief history of computation of earthquake response spectra. Files of seismological field survey, noaa, san francisco. A response spectrum for one earthquake in a specified direction is not a smooth. This script aims to offer the shock response spectrum of an acceleration time history of an earthquake which is known. Maps are then downloaded as pdf files or postscript files. Current practice for the development of floor design response spectra meets a. Chapter 3 development of sitespecific response spectra for. Abovementioned document revision 1 is of february 1978. Pdf reliability analysis of uncertain structures using. This online engineering pdh course presents the response spectrum method of earthquake response analysis of simple structures and mechanicalelectrical equipment. The method presented in this course is widely used and is applicable to any structure or equipment that can be modeled as a singledegreeoffreedom sdof system. Dynamic analysis using response spectrum seismic loading before the existence of inexpensive personal computers, the response spectrum method was the standard approach for linear seismic analysis 15.
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. Inelastic seismic response of structures civildigital. Such spectra are called instructure response spectra or floor response spectra. Include response spectrum analysis load case through layout window load cases. Recommendations for shape of earthquake response spectra nrc.
The procedure that has been used by nicolaou 1998 was utilized also here to obtain the earthquake acceleration time history for sleman, yogyakarta, indonesia. Introduction the most direct description of an earthquake motion in time domain is provided by accelerograms that are recorded by instruments called strong motion accelerographs. The response spectrum method was the standard approach. Methodology for developing design response spectrum for use. The earthquake ground motion and response spectra design for sleman, yogyakarta, indonesia with probabilistic seismic hazard analysis and spectral matching in time domain article pdf available. This response spectrum will depend on the damping ratio and thegroundmotionselected. Using the acceleration response spectrum, an equivalent static load is derived which will provide the same maximum response as that obtained in each. Brief history of computation of earthquake response spectra m. Pdf response spectrum analysis of structures subjected to. The earthquake ground motions have a peak ground acceleration of 0. Introduction three traditional seismic analysis methods are proposed including equivalent static, response spectrum and timehistory analysis 1. Seismic analysis of highrise building using response spectrum method pratik bawankar1 1g. This paper deals with response spectrum method and its application to various types of the structures. The procedure is based on minimizing the differences between the target spectrum and ath response spectrum in a least square sense.
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