The main reasons for the widespread use of this method are. Response spectrum method of analysis with simplified. Earthquake resistant design of a transformer wit press. Why use spreadsheets for seismic site response analysis. The sdof response spectrum method usually gives less conservative results than simplified procedures, yet easy to. Seismic performance of tmds in improving the response of. The towering structure or highrise buildings is generally calculated using the response spectrum method, and flat rack or largespan structure is. By superposition of different modes of response, spectrum techniques can be applied o the design and analysis of complex structures such as buildings and dams. Seismic data consists of a series of recorded wiggle traces that describe a set of echoes from interfaces between rock layers in the subsurface that have. The report can also be downloaded in pdf form from the. The cqc method should be used to combine modal maxima in.
Construction of design response spectrum the chilean way eps 256. Generation of responsespectrumcompatible artificial. Chapter 3 development of sitespecific response spectra. The use of the response spectrum method in earthquake engineering must be terminated.
The response spectrum method was the standard approach. Response spectrum method and time history analysis are widely used in the seismic design of buildings. For this project, a site specific seismic study was performed to produce a smooth, uniform hazard, response spectrum based on the seismic parameters used in the. 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. Eurocode 8 compliant real record sets for seismic analysis. Those response spectra can be used as basis to design the story building with high up to 40 m. First of all, it is necessary to build the acceleration elastic response spectrum for the site of. Ii are merged into zone ii in fifth revision of code. Accidental eccentricity for response spectrum analysis. Finite element seismic analysis of guyed masts ii acknowledgments i would like to thank my supervisors, dr martin williams and dr tony blakeborough for their guidance and support during my studies here at oxford. Pdf this paper develops a probabilistic methodology for the seismic reliability analysis of structures with random.
Ghannadiasl1 in this paper, the e ectiveness of tuned mass dampers tmds in controlling building structures under earthquake excitations is studied through investigating the practical considerations and. The results from the mrs analysis are compared with the results obtained from an equivalent lateral force elf analysis of the same frame. The equivalence is restricted to a single mode of vibration. 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. New developments in the response spectrum method have led to calculations in seismic stresses that are more accurate, and usually lower, than those obtained by conventional methods. The acceleration response spectra is represented as piecewise linear segments, whose endpoints are defined by a time, acceleration coordinate. Seismic analysis of highrise building using response spectrum method pratik bawankar1 1g. The use of the response spectrum method in earthquake. Earthquake analysis and design of simple structures and. There was no attempt by the authors to homogenize combine the.
In addition, the result is response spectrum design the target spectrum and matching spectrum in figure 14. In many engineering applications, one requires maximum absolute quantities experienced by the structure during the earthquake of interest. Determining the response spectrum from a given set of accelerograms is quite a wellcodified procedure. Site specific ground response and liquefaction analyses for a project site in new madrid seismic zone.
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. Seismic analysis comparison between response spectrum and timehistory method on modern hvdc thyristor valves di jiejian, zhaoyuxia,wu xiaofeng, sun qiguo and liu fengbin department of mechatronics engineering department of mechatronics engineering north china university of technology north china university of technology. Response spectrum method of analysis free download as powerpoint presentation. International conferences on recent advances in geotechnical earthquake engineering and soil. 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. Response spectra from the 1989 loma prieta, california, earthquake regressed for site amplification, attenuation, and directivity openfile report 97858 by. Construction of design response spectrum the chilean way. Design of structures, components, equipment and systems nrc. 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. Earthquake response spectrum analysis of offshore platforms h.
Used in this manner the spectrum technique represents an approach intermediate between a design based on static loads and a complete integration of the equations of motion of. Gupta group leader, civil engineering group birla institute of technology and science pilani, rajasthan333031. Eurocode 8 compliant real record sets for seismic analysis of. For each mode, a response is read from a design spectrum based on the modal frequency and a given damping ratio. Methods of ground motion recording and correction are first presented, followed by a discussion of ground motion characteristics including peak ground motion, duration of strong motion, and frequency content. Figure 9 acceleration response spectrum for the 1940 imperial valley earthquake. Displacement and acceleration design spectra for seismic. Chapter 3 development of sitespecific response spectra for.
Analysis psha aims to quantify these uncertainties, and combine them to produce an. The resulting plot can then be used to pick off the response of any linear system, given its natural frequency of oscillation. To encourage consensus and consistency in the state of the practice going forward, recommendations related to selecting and scaling ground motions for design and performance assessment of low. On the other hand the generation of the accelerograms from the knowledge of a target response spectrum is an inverse problem whose solution is not unique.
This online engineering pdh course presents the response spectrum method of earthquake response analysis of simple structures and mechanicalelectrical equipment. The details of ground motions and their characteristics considered for the analys are presented in table 1. Pdf response spectrum analysis of structures subjected to. Seismic analysis of safetyrelated nuclear structures and. The response spectrum analysis rsa method has been widely used in. Do you want to perform earthquake analyses according to design codes or just in order to verify your structure. Pdf reliability analysis of uncertain structures using earthquake. Earthquake response spectrum analysis of offshore platforms. Published on december 8, 2015 december 8, 2015 20 likes 9 comments. Response spectrum method in seismic analysis and design of. Earthquake response spectra and factors that influence their characteristics such as soil.
Seismic site response analysis using spreadsheets geraldo r. 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. The earthquake ground motion and response spectra design. A response spectrum is a plot of maximum response of a single degree of freedom system subject to a specific input, such as step. Floor response spectra generation for seismic design of buildings. Spectral analysis is used to combine the effect of the structures modes. This chapter surveys the stateoftheart work in strong motion seismology and ground motion characterization. Finally, the technical report of the analysis can be created onthefly in pdf, rtf.
A responsespectrum 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. Hence, it is essential to consider the seismic load for the design of multistoried building. Equivalent lateral force for an earthquake is defined as a set of lateral force which will produce the same peak response as that obtained by dynamic analysis of structures. Dec 08, 2015 the use of the response spectrum method in earthquake engineering must be terminated. Peak ground motion, power spectral density, response modification factors, response spectrum. Why response spectrum approach in earthquake geotechnical engineering. Eurocode 8 compliant record sets for seismic analysis of structures 57 when following eurocode 8 criteria described next, these procedures for record selection are not readily applicable because. Introduction seismic design response spectrum seismic design category irregularity redundancy introduction transition from sni gempa 2002 to sni gempa 201x sni gempa 2002 sni gempa 201x overview on seismic response spectrum generating design response spectrum using the new seismic map mapped spectral acceleration at mce level. The paper extends previous work by the authors on displacement and acceleration spectra for analysis and design of. Sep 10, 20 equivalent lateral force for an earthquake is defined as a set of lateral force which will produce the same peak response as that obtained by dynamic analysis of structures. 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.
Studies in this direction combine random vibration. Seismic analysis of highrise building using response. The current article describes in great detail two different approaches. In this chapter, earthquake excitation problems are treated as base excitation problems. Rete dei laboratori universitari di ingegneria sismica. 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. A plot of the peak value of a response quantity eg. Seismic response is taken as the average from five. The accelerograph records three orthogonal components of ground acceleration. Response spectra from the 1989 loma prieta, california.
Response spectrum analysis of structures subjected to seismic actions michalis fragiadakis laboratory for earthquake engineering, national technical university of athens n. Response spectrum analysis of structures subjected to seismic. 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. This new textbook examines the wealth of information on the response spectrum method generated by the latest research and presents the background theory in simplified form. The graph showing the variation of the maximum response maximum displacement, velocity, acceleration, or any other quantity with the natural.
Used in this manner the spectrum technique represents an approach intermediate between a. Site specific ground motion simulation and seismic response analysis for microzonation of kolkata3 in this region the method proposed by boore 1983, 2003 smsimprogram was applied to simulate the artificial ground motion using local seismotectonic parameters. That time history can be utilized to design the tall building in the district with high more than 40 m. Natural period of embankment subsoil system the model of embankment subsoil system shown in fig. Floor response spectra generation for seismic design of. Concepts in practical dynamic analysis situations we are interested in the maximum response. Pdf this report is the development of response spectrum analysis for mdof structure in matlab. Response spectrum method of analysis mechanical engineering.
Analysis of effects of vertical earthquake on building. To overcome the above difficulties, earthquake response spectrum is the most. Chapter 2 earthquake ground motion and response spectra. Chan ocean engineering department, lloyds register of shipping, 71 fenchurch street, london ec3m 4bs, uk received october 1986 response spectrum techniques for multicomponent seismic analysis of steel template offshore platforms are evaluated. This chapter uses the modal response spectrum mrs method of analysis to examine a sixstory momentresisting frame. Selecting and scaling earthquake ground motions for. Response spectrum analysis of structures subjected to. Seismic response is taken as the average from five analyses. The current research of vertical seismic impact focus on the towering structure, highrise buildings, flat rack and large span structures. The main objective of the study elaborated in the full thesis version is, in a first phase linear range 9, to. Evaluation of modal combination methods for seismic response. The earthquake ground motion and response spectra design for.
A normalised velocity response spectrum model was first developed by the australian geological survey organisation agso based. 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. Working with such respected and inspirational individuals has been a privilege and has confirmed my interest in advanced. Response spectrum analysis is the dominant contemporary method for dynamic analysis of building structures under seismic loading. Concepts in practical dynamic analysis situations we are interested in the maximum. 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. 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. Site specific ground motion simulation and seismic.
Development of sitespecific response spectra for seismic analysis of concrete hydraulic structures section i introduction 31. Earthquake ground motion and response spectra springerlink. Site specific ground response and liquefaction analyses. Seismic performance of tmds in improving the response of mrf buildings s. Seismic analysis of safetyrelated nuclear structures and commentarydoe nph meeting. The objective of this project was to reevaluate the current regulatory guidance for combining modal responses in response spectrum analysis, evaluate recent technical developments, and recommend revisions to the regulatory guidance. Purpose and scope this chapter describes procedures for developing sitespecific response spectra of ground motions throughout the united states for seismic analyses of hydraulic structures. The response spectrum method of analysis is developed using the following steps.
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