Earthquakes response spectrum

Figure 1. Category 3 plates earthquake response spectrum.

Muscolino G, Palmeri A (2007) An earthquake response spectrum method for linear light secondary substructures. ISET J Earthq Technol 44 193-211 Nakashima M, Saburi K, Tsuji B (1996) Energy input and dissipation behaviour of structures with hysteretic dampers. Earthq Eng Struct Dyn 25 483-496 Ozcan O, Binici B, Ozcebe G (2008) Improving seismic performance of deficient reinforced concrete columns using carbon fiber-reinforced polymers. Eng Struct 30 1632-1646... 

This is the response spectrum, constructed for a particular location, for a future earthquake. It is based on seismic studies conducted for that region and past seismic records of and around that region, if available. It forms the basic parameters for the design and testing of an object. 

Ground acceleration This is the time history of ground acceleration as a result of an earthquake, where multiple frequency excitation predominates (Figure 14.12(b). A ground response spectrum (GRS) can be derived from this history. 

Response spectrum recorders are not supplied as discrete instruments. A permanently installed response spectrum analyzer provides more complete information than that provided by response spectrum recorders. Data from the strong motion accelerometers are fed into the response spectrum analyzer to produce earthquake spectra immediately following an earthquake. The response spectrtun analyzer is located in the Reactor Service Building with readout both there and in the Control Room. This system achieves the intent of Regulatory Guide 1.12, Revision 1. (Ref. 13)... 

The Modal Response Spectrum Analysis (also known as a dynamic analysis) more accurately depicts the response of the structure to the earthquake. This is done by considering the response of multiple modes instead of just the first one (as is done in the ELF). Whereas the use of a static analysis assumes that a load is applied relatively slowly, a dynamic analysis should be used if the application of the load is faster than the response of the structure. For this reason a dynamic analysis is mainly... 

The Disassembly Basins were designed and constructed to be qualified for a blast load and a nominal O.lg earthquake statical applied to the dead and live load (Ref 8-28). This included a foundation investigafion by the US Army Corps of En neers. The Disassembly Basin walls interi dng whh the reactor building were later reviewed (Blume) in 1967 for st-0 2g Housner response spectrum (Ref 8-28). A recent structural scoping study assessment reveals the K-Reactor Disassembly Basin exterior walls and foundations should be capable of vdtbstanding a... 

Regardless of the exposure to seismic hazard, an SI 2 design basis earthquakes should be adopted for every nuclear power plant for the design of safety classified items. The minimum level should correspond to a peak ground acceleration of O.lg (zero period of the design response spectrum), to be considered at the free field. A unified, site compatible spectrum should be associated with this peak ground acceleration value. In this case SL-1 may be assumed to be coincident with SL-2. 

When the output of the numerical analysis is requested in terms of floor response spectra, maximum relative displacements, relative velocities, absolute accelerations and maximum stresses during an earthquake, linear dynamic analysis (e.g. direct time integration, modal analysis, frequency integration and response spectrum) is generally adequate for most models. Alternatively, non-hnear dynamic analysis should be used where appropriate or necessary (e.g. structural hft-off, non-linear load dependent support, properties of foundation materials in soil-structure interaction problems or interactions between solid parts). 

For nonlinear response history analyses (NRHA), three different earthquake records are employed with characteristics listed in Table 1. These records are appropriately scaled to match a smoothed elastic response spectrum as shown in Figure 3. In the analysis PERFORM-3D structural analysis program (CSI 2006) has been utilized. 

Aydinoglu, M.N. 2003. An incremental response spectrum analysis based on inelastic spectral displacements for multi-mode seismic performance evaluation. Bulletin of Earthquake Engineering l(l) 3-36. 

Aydinoglu, M.N. 2007. A Response Spectrum-Based Nonlinear Assessment Tool for Practice Incremental Response Spectrum Analysis (IRSA). Special Issue Response Spectra (Guest Editor M.D. Trifunac), ISET Journal of Earthquake Technology 44(1), No. 481. 

Cough, R. W. Earthquake analysis by response spectrum superposition, Bulletin Seismo-logical Society America, Vol. 52, No. 3, 1962. 

The conditional spectrum (CS) is a target response spectrum (with mean and variance) for ground motion selection to perform nonlinear dynamic analysis. The computation of the CS requires (1) input earthquake parameters of magnitude, distance, relevant seismological and site characteristics (e.g., fault type and soil type) ... 

Wang G (2011) A ground motion selection and modification method capturing response spectrum characteristics and variability of scenario earthquakes. Soil Dyn Earthq Eng 31 (4) 611-625... 

Earthquake Response Spectra and Design Spectra, Fig. 1 A typical response spectrum plot... 

The relative velocity response spectrum, usually of secondary importance, is related to the maximum strain energy of the SDOF system, i.e., SV is equal to the velocity that gives the SDOF system kinetic energy equal to the maximum strain energy due to the earthquake ground motion. This follows from the definition of strain energy and substitution from Eq. 7, i.e.. 

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