scholarly journals Questioning the applicability of soil amplification factors as defined by NEHRP (USA) in the Israel building standards

2012 ◽  
Vol 04 (08) ◽  
pp. 631-639 ◽  
Author(s):  
Yuli Zaslavsky ◽  
Avi Shapira ◽  
Marina Gorstein ◽  
Nahum Perelman ◽  
Galina Ataev ◽  
...  
2013 ◽  
Vol 40 (5) ◽  
pp. 483-498 ◽  
Author(s):  
M. Saatcioglu ◽  
M. Shooshtari ◽  
S. Foo

Seismic screening software is developed for existing buildings in Canada on the basis of the requirements of 2010 National Building Code of Canada. The software is based on the “Manual for Screening of Buildings for Seismic Investigation,” published by the National Research Council of Canada in 1992. The new software incorporates updated seismicity and soil classifications used in the National Building Code of Canada (NBCC) since 2005, as well as the new ductility and over-strength factors specified in the 2010 NBCC. The uniform hazard spectrum values of the current Canadian seismicity, defined for each municipality in Canada with a 2500 year earthquake return period, are used as reference hazard values. Seismic risk associated with the use of older seismic hazard values specified in older editions of the NBCC is identified relative to the current reference seismicity. The new site classifications are incorporated, while establishing relative soil amplification values between the new acceleration-based and velocity-based soil amplification factors and the foundation factors used in older codes. The new ductility and over-strength factors used in recent editions of the code are introduced in identifying different structural types with different toughness and energy dissipation capacities. The software can be used to conduct seismic screening of buildings located in different municipalities in Canada relative to the seismic requirements of NBCC-2010. It can also be used to generate tables for different locations in the country for manual screening of buildings.


Author(s):  
Roberto Paolucci ◽  
Mauro Aimar ◽  
Andrea Ciancimino ◽  
Marco Dotti ◽  
Sebastiano Foti ◽  
...  

AbstractIn this paper the site categorization criteria and the corresponding site amplification factors proposed in the 2021 draft of Part 1 of Eurocode 8 (2021-draft, CEN/TC250/SC8 Working Draft N1017) are first introduced and compared with the current version of Eurocode 8, as well as with site amplification factors from recent empirical ground motion prediction equations. Afterwards, these values are checked by two approaches. First, a wide dataset of strong motion records is built, where recording stations are classified according to 2021-draft, and the spectral amplifications are empirically estimated computing the site-to-site residuals from regional and global ground motion models for reference rock conditions. Second, a comprehensive parametric numerical study of one-dimensional (1D) site amplification is carried out, based on randomly generated shear-wave velocity profiles, classified according to the new criteria. A reasonably good agreement is found by both approaches. The most relevant discrepancies occur for the shallow soft soil conditions (soil category E) that, owing to the complex interaction of shear wave velocity, soil deposit thickness and frequency range of the excitation, show the largest scatter both in terms of records and of 1D numerical simulations. Furthermore, 1D numerical simulations for soft soil conditions tend to provide lower site amplification factors than 2021-draft, as well as lower than the corresponding site-to-site residuals from records, because of higher impact of non-linear (NL) site effects in the simulations. A site-specific study on NL effects at three KiK-net stations with a significantly large amount of high-intensity recorded ground motions gives support to the 2021-draft NL reduction factors, although the very limited number of recording stations allowing such analysis prevents deriving more general implications. In the presence of such controversial arguments, it is reasonable that a standard should adopt a prudent solution, with a limited reduction of the site amplification factors to account for NL soil response, while leaving the possibility to carry out site-specific estimations of such factors when sufficient information is available to model the ground strain dependency of local soil properties.


Author(s):  
Jiacheng Zhou ◽  
Chao Hu ◽  
Ziqiu Wang ◽  
Zhengfa Ren ◽  
Xiaoyu Wang ◽  
...  

By studying dynamic characteristics of the leaf spring system, a new elastic component is designed to reduce the working load and to a certain extent to ensure the linearity as well as increase the amplitude in the vertical and horizontal directions in vibration screen. The modal parameters, amplitudes, and amplification factors of the leaf spring system are studied by simulation and experiment. The modal results show that the leaf spring system vibrates in horizontal and vertical directions in first and second mode shapes, respectively. It is conducive to loosening and moving the particles on the vibration screen. In addition, it is found that the maximum amplitude and amplification factor in the horizontal direction appear at 300 r/min (5 Hz) while those in the vertical direction appear at 480 r/min (8 Hz), which are higher than those in the disc spring system. Moreover, the amplitude of the leaf spring system increases proportionally with the increase of exciting force while the amplification factors are basically the same under different exciting forces, indicating the good linearity of the leaf spring system. Furthermore, the minimum exciting force occurs in the leaf spring system under the same amplitude by comparing the exciting force among different elastic components. The above works can provide guidance for the industrial production in vibration screen.


2021 ◽  
pp. 136943322110032
Author(s):  
Lin Ma ◽  
Wei Zhang ◽  
Steve C.S. Cai ◽  
Shaofan Li

In this paper, the dynamic amplification factors (DAFs) of high-speed railway continuous girder bridges are studied. The vehicle-bridge interactions (VBIs) of 13 concrete continuous girder bridges with spans ranging from 48 to 130 m are analyzed, the influences of the train speed, the train marshalling and the bridge fundamental frequency on the DAF are investigated, and the DAF design standard for high-speed railway bridges is discussed. The results indicate that for the continuous beam bridge whose fundamental frequency is less than 3.0 Hz, the maximum DAF is no more than 1.15; while for the bridge examples with a fundamental frequency larger than 3.0 Hz, the maximum DAF reaches 1.25 because the resonance occurs at high train speed. The empirical formulas of the DAFs in the Japan Railway Technical Research Institute (JRTRI) code could provide a conservative estimation of the DAFs of high-speed railway continuous bridges.


1997 ◽  
Vol 87 (2) ◽  
pp. 356-369
Author(s):  
Takumi Toshinawa ◽  
J. John Taber ◽  
John B. Berrill

Abstract The areal distribution of seismic ground-motion intensity in the city of Christchurch, New Zealand, during the 1994 Arthurs Pass Earthquake (ML 6.6) was evaluated using an intensity questionnaire together with local site amplifications inferred from seismic recordings and microtremors. In order to estimate the intensity in parts of the city where no intensity data were available, intensity data were compared to relative levels of shaking determined from both weak-motion and microtremor recordings. Weak ground-motion amplification factors were determined using ratios of ground accelerations at five sediment sites with respect to a rock site. Microtremor amplification factors were determined from horizontal-to-vertical spectral ratios at a 1-km spacing throughout the city. A positive correlation between weak-motion and microtremor amplification factors allowed extrapolation of microtremor amplification to estimated MM intensity (EMMI). EMMI ranged from 3 to 6 and was consistent with the questionnaire intensity and geological conditions and showed detailed information on the areal distribution of ground-motion intensity in the city.


2021 ◽  
Author(s):  
Lisa Godsey

This complete guide to the selection of materials for interiors has been updated to reflect the most recent materials on the market and contemporary awareness on industry movements like sustainability. Written from the viewpoint of the working designer, Interior Design Materials and Specifications, 4th Edition, describes each material's characteristics and teaches students how to evaluate, select, and specify materials, taking into account factors including code compliance, building standards, sustainability guidelines, human needs, and bidding processes. Students will learn how to communicate with suppliers and vendors to achieve the results they envision and how to avoid some of the pitfalls common to material selection and specification.


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