scholarly journals PRE-SHOT SIMULATIONS OF NEAR-FIELD AND FAR-FIELD GROUND MOTION FOR THE SOURCE PHYSICS EXPERIMENT (SPE) EXPLOSIONS AT THE CLIMAX STOCK, NEVADA NATIONAL SECURITY SITE: SPE3

2012 ◽  
Author(s):  
R Mellors ◽  
A Pitarka ◽  
A Rodgers ◽  
W Walter ◽  
S Ford ◽  
...  





2013 ◽  
Vol 275-277 ◽  
pp. 1466-1470
Author(s):  
Yang Liu ◽  
Wen Guang Liu ◽  
Wen Fu He ◽  
Qiao Rong Yang

The equivalent velocity spectrum as a new ground motion intensity measure (IM) characterization parameter is proposed in this paper. 44 far field ground motions and 20 near-field high-speed pulse seismic waves were used for single-degree-freedom (SDOF) nonlinear time history analysis, respectively. The correlations between five IMs and maximum deformation for SDOF at various periods and different yield coefficients were analyzed. The results show that for the structures with medium-to-long period, the correlation coefficient average value of the proposed equivalent speed and maximum deformation is more than 0.6, and maximum of those is more than 0.9. The correlation coefficient average value by using the proposed equivalent speed under far field ground motions is more than those under near field ground motions. The P-delta effect on the correlation coefficients between proposed IM for the structures with medium-to-short period is significant



1975 ◽  
Vol 12 (4) ◽  
pp. 523-538
Author(s):  
H. S. Hasegawa

Ground motion and residual ground deformation at strategic points in the epicentral region of an idealized, vertical shear fault that may correspond to an intermediate magnitude (6–6½) earthquake are displayed and analyzed. For analytical purposes, Haskell's expressions for the elastic displacements near a propagating fault are separated into two parts, the near-field and the far-field terms. The distance from the fault at which the far-field terms are sufficient to describe the total field varies, depending upon the orientation of particle motion relative to that of the dislocation (slip) vector. For the component of particle motion parallel to the dislocation vector, this distance is comparatively greater than that for the perpendicular component. The Earth Physics Branch strain gauge, which has a threshold sensitivity of about 5 × 10−10, has the capability of detecting residual strain at least as far as 100 km from the hypothetical fault. The Earth Physics Branch tiltmeter, which can detect a step change in tilt in the range 5 × 10−9 to 5 × 10−10 radians, can detect residual tilt at least as far as 50 km from the causative fault.The high-frequency slope of the theoretical Fourier amplitude spectrum of ground acceleration (FS), is not appreciably steepened by the addition of the near-field to the far-field terms. The implication of this observation is that the steep slope observed at high frequencies on FS curves of predominantly California earthquakes cannot be attributed, even in part, to the source mechanism assumed but must be attributed entirely to travel path effects such as attenuation and scattering.



1989 ◽  
Vol 33 (2) ◽  
pp. 133-145
Author(s):  
V. Vavryčuk ◽  
A. Plešinger ◽  
K. Pěč
Keyword(s):  


2019 ◽  
Vol 5 (4) ◽  
pp. 759-766 ◽  
Author(s):  
Farzaneh Raji ◽  
Amir Naeiji

The characteristic of near-field earthquake records has been investigated in the previous studies. However, the effects of the near-field earthquakes on the response of the building structures need to be further investigated. Engineering demand parameters like inter-story drift ratio and floor acceleration can provide a good means for comparing the response of structures to the near-field and the far-field earthquakes. The main objective of this paper was to apply these two parameters to compare the behavior of the concrete Moment Resistant Frame (MRF) subjected to near-field and far-field ground motions. In this study, non-linear numerical simulations were performed on concrete MRF office buildings subjected to two sets of 14 near-field records and 14 far-field records. The analytical models simulated 4-story, 8-story, and 16 story buildings. The obtained results indicated that the near-field effects can increase the inter-story drift ratio and floor acceleration at lower stories of low and mid-rise building subjected to high ground motion intensities.





Author(s):  
M. Andi ◽  
H. Dashti-Naserabadi ◽  
M. Beyklarian

One of the factors affecting the dynamic state of the dams that may cause damages to the dam is the change under the spatial and temporal Excitation of the Heterogeneous ground Motion. Therefore, in different states the stress, strain, displacement and hydrostatic pressure indices are changed and led to serious damage to the dam. In this study, Karun 3 dam is investigated which is classified as one of the double curvature arch and gravity dams. For this purpose, using ABAQUS software, these indices have been investigated and controlled and the effectiveness of indices in this dam has been investigated in nonlinear dynamic seismic state. Northridge, Kobe, Bam, Hector, Chi-Chi and Manjil earthquakes are applied to the Karun 3 Dam. The results showed that due to the large amplitude and periodicity of the near-fault mappings, under the near-field earthquake, the deformation of the Karun 3 dam is greater than the far-field fault zone. As the height of the Karun 3 Dam rises, the effectiveness of far-field earthquakes declines and near-field earthquakes show more impact on the structure. In far-field earthquakes, stress changes due to earthquakes with maximum dynamic acceleration, the relative percentage of mises stress change is 15.5% and maximum dam crest change is 68.5 mm, and for near-field earthquakes is 25% and maximum dam crest change is 100 mm.



2017 ◽  
Author(s):  
Margaret Townsend ◽  
Curtis Obi ◽  
Robert Abbott ◽  
Robert Mellors ◽  
Ken Smith ◽  
...  


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