The island of Hawaii earthquakes of November 29, 1975: Strong-motion data and damage reconnaissance report

1977 ◽  
Vol 67 (2) ◽  
pp. 493-515
Author(s):  
Christopher Rojahn ◽  
B. J. Morrill
Keyword(s):  
Local Time ◽  
Structural Damage ◽  
Strong Motion ◽  
Maximum Acceleration ◽  
Epicentral Area ◽  
Ground Shaking ◽  
Motion Data ◽  
Large Sector ◽  
Threshold Duration ◽  
Strong Ground

Abstract Two earthquakes occurred on the island of Hawaii on November 29, 1975, a magnitude (Ms) 5.7 event at 0335 (local time) and a magnitude (Ms) 7.2 event at 0447. During the larger event, a maximum acceleration of 0.22 g was recorded in the southern part of Hilo, 43 km north of the epicenter. A 0.05 g threshold duration of 13.7 sec was measured for the same component. Smaller amplitude accelerograph records were obtained at two other locations on the island along with four seismoscope records. During or subsequent to the larger event, a large sector of the southeastern coastline subsided by as much as 3.5 meters. A tsunami generated by the larger event caused at least one death (one person also missing), injury to 28 persons, and significant structural and nonstructural damage. Only scattered evidence of strong ground shaking was observed in the epicentral area, and most of the several dozen nearby structures sustained little or no structural damage from ground shaking. In Hilo, 45 km north of the Ms = 7.2 epicenter, structural and nonstructural damage was slight to moderate but more extensive than elsewhere on the island.

scholarly journals The ShakeMaps of the Amatrice, M6, earthquake

2016 ◽  
Vol 59 ◽  
Author(s):  
Licia Faenza ◽  
Valentino Lauciani ◽  
Alberto Michelini
Keyword(s):  
Ground Motion ◽  
Data Exchange ◽  
Main Shock ◽  
Central Italy ◽  
Strong Motion ◽  
Rupture Directivity ◽  
Time Data ◽  
Epicentral Area ◽  
Ground Shaking ◽  
Motion Data

In this paper we describe the performance of the ShakeMap software package and the fully automatic procedure, based on manually revised location and magnitude, during the main event of the Amatrice sequence with special emphasis to the M6 main shock, that struck central Italy on the 24th August 2016 at 1:36:32 UTC. Our results show that the procedure we developed in the last years, with real-time data exchange among those institutions acquiring strong motion data, allows to provide a faithful description of the ground motion experienced throughout a large region in and around the epicentral  area. The prompt availability of the rupture fault model, within three hours after the earthquake occurrence, provided a better descriptions of the level of strong ground motion throughout the affected area.  Progressive addition of  station data and  manual verification of the data insures improvements in the description of the experienced ground motions.  In particular, comparison between the MCS intensity shakemaps and preliminary field macroseismic reports show favourable similarities.  Finally the overall  spatial pattern of the ground motion of the main shock is consistent with reported rupture directivity toward NW and reduced levels of ground shaking toward SW probably linked to the peculiar source effects of the earthquake.

A State-of-Knowledge Review of the Influence of Strong-Motion Duration on Structural Damage

2006 ◽  
Vol 22 (3) ◽  
pp. 827-845 ◽  
Author(s):  
Jonathan Hancock ◽  
Julian J. Bommer
Keyword(s):  
Structural Damage ◽  
Strong Ground Motion ◽  
Strong Motion ◽  
Strong Correlations ◽  
Review Of The Literature ◽  
Cumulative Energy ◽  
Ground Shaking ◽  
Soil Deposits ◽  
Structural Demand ◽  
Strong Ground

The important role played by the duration of ground shaking in the response of saturated soil deposits is universally acknowledged, but no such consensus exists regarding the degree of influence that duration exerts on structural damage. There are several hundred papers in the literature that link structural damage to parameters related either directly or indirectly to the duration of strong ground motion. The conclusions of these studies differ widely with regard to the influence of strong-motion duration on structural demand. This paper provides a summary and critical review of the literature on this subject. It is found that studies employing damage measures related to cumulative energy usually find a positive correlation between strong-motion duration and structural damage, while studies employing damage measures using maximum response generally do not find strong correlations between duration and damage.

Nonlinear behavior of soil sediments identified by using borehole records observed at the Ashigra Valley, Japan

1995 ◽  
Vol 85 (6) ◽  
pp. 1821-1834
Author(s):  
Toshimi Satoh ◽  
Toshiaki Sato ◽  
Hiroshi Kawase
Keyword(s):  
Shear Strain ◽  
Main Part ◽  
Nonlinear Behavior ◽  
Strong Motion ◽  
S Wave ◽  
Ground Shaking ◽  
Wave Velocities ◽  
The One ◽  
Soil Sediments ◽  
Strong Ground

Abstract We evaluate the nonlinear behavior of soil sediments during strong ground shaking based on the identification of their S-wave velocities and damping factors for both the weak and strong motions observed on the surface and in a borehole at Kuno in the Ashigara Valley, Japan. First we calculate spectral ratios between the surface station KS2 and the borehole station KD2 at 97.6 m below the surface for the main part of weak and strong motions. The predominant period for the strong motion is apparently longer than those for the weak motions. This fact suggests the nonlinearity of soil during the strong ground shaking. To quantify the nonlinear behavior of soil sediments, we identify their S-wave velocities and damping factors by minimizing the residual between the observed spectral ratio and the theoretical amplification factor calculated from the one-dimensional wave propagation theory. The S-wave velocity and the damping factor h (≈(2Q)−1) of the surface alluvial layer identified from the main part of the strong motion are about 10% smaller and 50% greater, respectively, than those identified from weak motions. The relationships between the effective shear strain (=65% of the maximum shear strain) calculated from the one-dimensional wave propagation theory and the shear modulus reduction ratios or the damping factors estimated by the identification method agree well with the laboratory test results. We also confirm that the soil model identified from a weak motion overestimates the observed strong motion at KS2, while that identified from the strong motion reproduces the observed. Thus, we conclude that the main part of the strong motion, whose maximum acceleration at KS2 is 220 cm/sec2 and whose duration is 3 sec, has the potential of making the surface soil nonlinear at an effective shear strain on the order of 0.1%. The S-wave velocity in the surface alluvial layer identified from the part just after the main part of the strong motion is close to that identified from weak motions. This result suggests that the shear modulus recovers quickly as the shear strain level decreases.

scholarly journals The INGV real time strong motion data sharing during the 2016 Amatrice (central Italy) seismic sequence

2016 ◽  
Vol 59 ◽  
Author(s):  
Marco Massa ◽  
Ezio D'Alema ◽  
Chiara Mascandola ◽  
Sara Lovati ◽  
Davide Scafidi ◽  
...  
Keyword(s):  
Real Time ◽  
Data Sharing ◽  
Strong Motion ◽  
Main Task ◽  
Seismic Sequence ◽  
Web Portal ◽  
Epicentral Area ◽  
Strong Motion Data ◽  
Motion Data ◽  
The Web

<p><em>ISMD is the real time INGV Strong Motion database. During the recent August-September 2016 Amatrice, Mw 6.0, seismic sequence, ISMD represented the main tool for the INGV real time strong motion data sharing.  Starting from August 24<sup>th</sup>,  the main task of the web portal was to archive, process and distribute the strong-motion waveforms recorded  by the permanent and temporary INGV accelerometric stations, in the case of earthquakes with magnitude </em><em>≥</em><em> 3.0, occurring  in the Amatrice area and surroundings.  At present (i.e. September 30<sup>th</sup>, 2016), ISMD provides more than 21.000 strong motion waveforms freely available to all users. In particular, about 2.200 strong motion waveforms were recorded by the temporary network installed for emergency in the epicentral area by SISMIKO and EMERSITO working groups. Moreover, for each permanent and temporary recording site, the web portal provide a complete description of the necessary information to properly use the strong motion data.</em></p>

The identification of building structural systems

1976 ◽  
Vol 66 (1) ◽  
pp. 125-151
Author(s):  
Firdaus E. Udwadia ◽  
Panos Z. Marmarelis
Keyword(s):  
Nonlinear Behavior ◽  
Strong Motion ◽  
Ambient Vibration ◽  
Structural Systems ◽  
Reinforced Concrete Structure ◽  
Earthquake Excitation ◽  
Ground Shaking ◽  
Ambient Vibration Testing ◽  
Suitable System ◽  
Strong Ground

abstract This paper investigates the response of structural systems to strong earthquake ground shaking by utilizing some concepts of system identification. After setting up a suitable system model, the Weiner technique of nonparametric identification has been introduced and its experimental applicability studied. The sources of error have been looked into and several new results have been presented on accuracy calculations stemming from the various assumptions in the Wiener technique. The method has been applied in studying the response of a 9-story reinforced concrete structure to earthquake excitation as well as ambient vibration testing. The linear contribution to the total roof response during strong ground shaking has been identified, and it is shown that a marked nonlinear behavior is exhibited by the structure during the strong-motion portion of the excitation.

30 Ooctober 2020 Samos-Sigacik Earthquake: On Strong Ground Motion and Local Site Amplification

2021 ◽  
Author(s):  
Eser Çakti ◽  
Karin Sesetyan ◽  
Ufuk Hancilar ◽  
Merve Caglar ◽  
Emrullah Dar ◽  
...  
Keyword(s):  
Ground Motion ◽  
Structural Damage ◽  
Strong Ground Motion ◽  
Epicentral Distance ◽  
Strong Motion ◽  
Aegean Sea ◽  
Site Amplification ◽  
Local Site ◽  
Basin Effects ◽  
Strong Ground

&lt;p&gt;The Mw 6.9 earthquake that took place offshore between the Greek island of Samos and Turkey&amp;#8217;s &amp;#304;zmir province on 30 October 2020 came hardly as a surprise. Due to the extensional tectonic regime of the Aegean and high deformation rates, earthquakes of similar size frequently occur in the Aegean Sea on fault segments close to the shores of Turkey, affecting the settlements on mainland Turkey and on the Greek Islands. Samos-Sigacik earthquake had a normal faulting mechanism. It was recorded by the strong motion networks in Turkey and Greece. Although expected, the earthquake was an&amp;#160; outstanding event in the sense of&amp;#160; highly localized, significant levels of building damage as a result of amplified ground motion levels. This presentation is an overview of strong ground motion characteristics of this important event both regionally and locally. Mainshock records suggest that local site effects, enhanced by basin effects could be responsible for structural damage in central Izmir, the third largest city of Turkey located at 60-70 km epicentral distance. We installed a seven-station network in Bayrakl&amp;#305; and Kar&amp;#351;&amp;#305;yaka districts of &amp;#304;zmir within three days of the mainshock in search of site and basin effects.&amp;#160; Through analysis of recorded aftershocks we explore the amplification characeristics of soils in the two aforementioned districts&amp;#160; and try to understand the role basin effects might have played in the resulting ground motion levels and consequently damage.&amp;#160;&lt;/p&gt;

The 23 October 2011 MW7.0 Van (Eastern Turkey) Earthquake: Interpretations of Recorded Strong Ground Motions and Post-Earthquake Conditions of Nearby Structures

2014 ◽  
Vol 30 (2) ◽  
pp. 657-682 ◽  
Author(s):  
V. Akansel ◽  
G. Ameri ◽  
A. Askan ◽  
A. Caner ◽  
B. Erdil ◽  
...  
Keyword(s):  
Fault Plane ◽  
Ground Motions ◽  
Hanging Wall ◽  
Strong Motion ◽  
Thrust Fault ◽  
Building Structures ◽  
Epicentral Area ◽  
Historical Structures ◽  
Strict Compliance ◽  
Strong Ground

A major thrust-fault earthquake of MW = 7.0 occurred on 23 October 2011 at 10:41:21 UTC in the eastern Anatolian region of Turkey, severely affecting the nearby towns of Van and Erciş. In this study, a few strong-motion records from the epicentral area are analyzed in order to investigate the characteristics of the ground motions. Also reported are the post-earthquake field observations for various types of structures, such as buildings, bridges, historical structures, tunnels, and dams within the vicinity of the fault plane. The spatial distribution of damage indicates a noticeable hanging-wall effect. The special-type structures are observed to experience far less damage, as opposed to the building structures in the region pointing to the need for strict compliance to seismic building code and the corresponding construction requirements.

A study of Puget Sound strong ground motion

1981 ◽  
Vol 71 (3) ◽  
pp. 883-903
Author(s):  
Charles A. Langston
Keyword(s):  
Wave Propagation ◽  
Puget Sound ◽  
Strong Motion ◽  
Complex Data ◽  
Lateral Heterogeneity ◽  
P Waves ◽  
Motion Data ◽  
Motion Models ◽  
Short Period ◽  
Strong Ground

abstract An attempt was made to model strong motion velocities and displacements from the 1965 Puget Sound earthquake. Teleseismic P waves recorded at Tumwater, Washington, were also examined to place constraints on allowable interface contrasts and to determine whether lateral heterogeneity is a major factor affecting wave propagation. Although strong motion models qualitatively showed many of the characteristics of near-vertical wave propagation in layered structures, the amplitude behavior of individual stations was quite complex. Data from Tacoma and Seattle sites attained lower velocities and acceleration compared to Olympia. The amplitude behavior is consistent with higher attenuation under Tacoma and Seattle although this is not strictly required. The short-period P data recorded at Tumwater show evidence of large velocity contrast interfaces under the station consistent with those assumed in the crustal models. The teleseismic data also indicated that dipping structure or other lateral heterogeneity is important for Olympia structure. Irrespective of these wave propagation problems, the largest single factor which has affected the level of strong ground motions in Puget Sound is the large source depth of past earthquakes. Thus, estimates of seismic hazard based on a direct interpretation of the strong motion data of the 1965 and 1949 events will be erroneously biased toward less hazard if there is potential for shallow faulting in the Puget depression.

Sign in / Sign up

Export Citation Format

Share Document