scholarly journals Accelerograph recordings of the Musa earthquake, 16 September, 1972

1976 ◽  
Vol 9 (2) ◽  
pp. 115-121
Author(s):  
B. Gaull
Keyword(s):  
Ground Motion ◽  
Ultramafic Complex ◽  
Peak Ground Accelerations ◽  
Dam Site ◽  
The Difference ◽  
Lower Site

On 16 September, 1972 at 04 15 09.8 UT an earthquake of magnitude ML 5.0 occurred in southeast Papua within about 20 km of a proposed dam site on the Musa River. The earthquake triggered two accelerographs, Musa A and Musa B, one at the crest and one at the base of the dam site. The peak ground accelerations recorded by the accelerographs were 1.85 m/s2 and 0.39 m/s2 respectively; the peak ground velocities were 87 mm/s and 2.0 mm/s; and the corresponding mean periods of the ground motion were about 0.23 and 0.04 s. The difference in the nature of the accelerograms is attributed to
the difference in the geological and topographical settings of the accelerograph sites. The upper site has an elevation of 406 m and consists of about 60 m of weathered sediments overlying fresh ultramafics. The lower site has an elevation of 112 m and consists of an outcrop of the ultramafic complex.

scholarly journals Attenuation of peak ground accelerations in New Zealand earthquakes

1997 ◽  
Vol 30 (2) ◽  
pp. 133-158 ◽  
Author(s):  
J. X. Zhao ◽  
D. J. Dowrick ◽  
G. H. McVerry
Keyword(s):  
New Zealand ◽  
Substantial Effect ◽  
Tectonic Plates ◽  
The Pacific ◽  
Source Distance ◽  
Shortest Distance ◽  
Soil Deposits ◽  
Peak Ground Accelerations ◽  
The Difference ◽  
Rock And Soil

The main result of this study is the development of attenuation expressions for peak ground accelerations (PGAs) in New Zealand earthquakes, in terms of magnitude Mw and shortest distance from the source. Other factors which are modelled are depth, focal mechanism, ground class and tectonic type of earthquake i.e. crustal, interface or dipping slab. As well as being implied in the source distance, the substantial effect of depth is modelled well with a separate linear depth term. For crustal events, focal mechanisms which are predominantly reverse are found to cause PGAs that are 28 percent stronger on average than for other mechanisms. PGAs at soil sites (ie those having soil deposits >3 m thick) are found to be 53 percent stronger on average than at other (ie rock) sites, but the difference between PGAs on rock and soil sites in large amplitude shaking remains uncertain, ie near the source o f events of Mw ≥ 7. Earthquakes occurring on the interface between the Pacific and Australian tectonic plates give rise to smaller PGAs than do crustal or slab events of the same magnitude, depth and distance. Comparisons are made between our New Zealand model and some for Europe, Japan and the Western USA.

Damage-Involved Response of Two Colliding Buildings under Non-Uniform Earthquake Loading

2013 ◽  
Vol 577-578 ◽  
pp. 197-200
Author(s):  
Robert Jankowski
Keyword(s):  
Ground Motion ◽  
Seismic Wave ◽  
Damage Model ◽  
Fem Analysis ◽  
Stochastic Modelling ◽  
Earthquake Loading ◽  
Non Linear ◽  
San Fernando ◽  
The Difference ◽  
Ground Motion Records

Pounding between insufficiently separated buildings, which may result in considerable damage or may even lead to the total collapse of colliding structures, has been repeatedly observed during earthquakes. Earthquake-induced collisions of buildings has been intensively studied applying various structural models. It was assumed in the analyses, however, that the seismic excitation is identical for all structural supports; whereas, in the reality, the ground motion differs from place to place due to spatial seismic effects connected with propagation of the seismic wave. The aim of the present paper is to conduct a detailed non-linear damage-involved analysis of pounding between two structures under non-uniform earthquake loading. A case of pounding between the Olive View Hospital main building and one of its stairway towers, observed during the San Fernando earthquake of 1971, has been considered in the study. In the numerical FEM analysis, non-linear material properties have been simulated using stiffness degradation (due to damage under cyclic loading) model of concrete and elastoplastic damage model of reinforcing steel. A method of conditional stochastic modelling has been used to generate the input ground motion records. The results of the study indicate that the incorporation of the non-uniform ground motion excitation may lead to substantial change of pounding-involved response of the structures. The difference between the uniform and non-uniform responses has been found to be relatively large considering the fact that the variation in the simulated input ground motion records was rather small. This shows the importance of incorporation in the damage-involved numerical analysis the effects connected with propagation of the seismic wave.

Near-source effects on the ground motion occurred at the Conza Dam site (Italy) during the 1980 Irpinia earthquake

2017 ◽  
Vol 15 (10) ◽  
pp. 4009-4037 ◽  
Author(s):  
Angelo Dello Russo ◽  
Stefania Sica ◽  
Sergio Del Gaudio ◽  
Raffaella De Matteis ◽  
Aldo Zollo
Keyword(s):  
Ground Motion ◽  
Source Effects ◽  
Dam Site

Telecom, Traffic Cones, and the Big One: Identifying Transportation and Communications Emergency Support Workforces and Calculating Their Exposure to Seismic Peak Ground Accelerations

2018 ◽  
Vol 2672 (1) ◽  
pp. 113-124
Author(s):  
Pierre M. Auza ◽  
Diana C. Lavery ◽  
R. Jayakrishnan ◽  
Yuko J. Nakanishi
Keyword(s):  
Disaster Response ◽  
Occupational Classification ◽  
Roles And Responsibilities ◽  
Recovery Planning ◽  
Frequency Table ◽  
Peak Ground Accelerations ◽  
Response And Recovery ◽  
The Mean ◽  
The Difference ◽  
Two Populations

Successful post-disaster response and recovery depends on prompt restoration of infrastructure, including transportation or communications. However, disasters can have an impact on the workforce responsible for restoration, for example, by damaging their homes. This study has two goals: 1. Identify workers potentially participating in restoring transportation and communications infrastructure; 2. Calculate these workers’ exposure to the peak ground accelerations (PGAs) of a 7.8 magnitude earthquake in a Southern California scenario, and compare it with the rest of the working population’s exposure. Four steps are required. First, calculate the mean PGA for each affected public use microdata area (PUMA). Second, identify the infrastructure restoration workforce by specifying Standard Occupational Classification (SOC) and North American Industry Classification System (NAICS) codes. When specifying, use the Emergency Support Function (ESF) Annexes for Transportation (ESF#1) and Communications (ESF#2) to clarify workers’ roles and responsibilities. This ESF-specific listing of codes is a novel contribution. Third, via frequency table, calculate the mean and standard deviation of transportation and communications workers’ exposure to PGAs in their PUMAs of residence. Finally, test the difference in mean PGA exposures between two populations: (a) transportation or communications workers and (b) the rest of the working population. This study finds that, for this scenario, transportation workers are exposed to statistically significant higher PGAs than non-transportation workers, and communication workers to significantly lower PGAs. For practitioners, knowing which worker categories a disaster disproportionately affects could justify pre-event investments in workforce preparedness and recovery planning efforts.

The contribution of sedimentation of algal cell to the downstream levels of musty odor

1995 ◽  
Vol 31 (11) ◽  
pp. 139-144
Author(s):  
T. Hoson ◽  
S. Hayashi ◽  
K. Hattori
Keyword(s):  
Lake Biwa ◽  
Algal Cell ◽  
Sampling Site ◽  
Late Summer ◽  
Early Summer ◽  
First Episode ◽  
Sinking Rate ◽  
The Difference ◽  
Two Peaks ◽  
Lower Site

In Lake Biwa, there are two peaks of 2-methylisoborneol (MIB) production, each of which is due to the different MIB producing algae, Phormidium and Oscillatoria. The former grows in early summer, whereas the latter grows in late summer. Levels of MIB were determined for water samples collected from Lake Biwa and the lower sampling site of Murano Water Treatment Plant's intake on Yodo River. MIB concentrations detected at the lower site differed between the two odor seasons. In the first episode due to growth of Phormidium, MIB level at the lower site was almost the same as that in the lake, whereas it was clearly lower than that of the lake in the second episode caused by Oscillatoria. No differences in flow ratio of the lake effluent to that of Yodo River were detected between the two odor seasons. Thus, the difference in MIB concentration between the lake and the lower site in the second episode may be caused by a decrease in cell-associated MIB due to the high sinking rate of Oscillatoria. The sinking rate ofOscillatoria trichome was twenty times higher than that of Phormidium.

Impact of partially non-ergodic site-specific probabilistic seismic hazard on risk assessment of single buildings

2020 ◽  
pp. 875529302093881
Author(s):  
Mohsen Kohrangi ◽  
Sreeram Reddy Kotha ◽  
Paolo Bazzurro
Keyword(s):  
Risk Assessment ◽  
Ground Motion ◽  
A Priori ◽  
Real Life ◽  
Site Specific ◽  
Risk Estimates ◽  
The Difference ◽  
Record Selection ◽  
Ground Motion Record Selection ◽  
The Impact

The growth of global ground-motion databases has allowed generation of non-ergodic ground-motion prediction equations (GMPEs) based on specific on-site recordings. Several studies have investigated the differences between the hazard estimates from ergodic versus non-ergodic GMPEs. Here instead we focus on the impact of non-ergodic PSHA estimates on the seismic risk of nonlinear single-degree-of-freedom systems representing ductile structures and compare it with the traditional risk estimates obtained using ergodic GMPEs. The structure-and-site-specific risk estimates depend not only on the difference in the hazard estimates but also on the different hazard-consistent ground-motion record selection that informs the response calculation. The more accurate structure-and-site-specific non-ergodic risk estimates show that traditional ones may be biased in a way impossible to predict a priori. Hence, the use of the non-ergodic approach is recommended, whenever possible. However, further advancements of non-ergodic GMPEs are necessary before being routinely utilized in real-life risk assessment applications.

scholarly journals STUDI PARAMETRIK DEFORMASI TORSI LANTAI BANGUNAN ASIMETRIS SEBIDANG DIPENGARUHI OLEH GEMPA PULSE DAN TANPA PULSE

2018 ◽  
Vol 9 (2) ◽  
Author(s):  
Ade Faisal ◽  
Gamal Halim
Keyword(s):  
Ground Motion ◽  
Mass Distribution ◽  
Earthquake Ground Motion ◽  
Centre Of Mass ◽  
Earthquake Loads ◽  
Earthquake Resistant ◽  
Low Stiffness ◽  
The Difference ◽  
Building Plans ◽  
Good Behaviour

Earthquake resistant building must be designed with a proper plan configuration. Although the regular and symmetrical building plans have been known to have a good behaviour under earthquake loads, but the facts have demonstrated that many asymmetrical plan buildings are built for the architectural reasons. Irregular plan buildings cause mass distribution, stiffness, and strength asymmetries which in turn produce the eccentricity to the centre of mass. In this research, the asymmetrical buildings are simulated under earthquake ground motion containing pulse. The study aims to evaluate the drift and floor rotations that occur in the asymmetrical buildings. The results indicate that the difference in drift of symmetrical and asymmetrical buildings reach 8% to 20%. The rotation occurred on the rigid side (high stiffness side) is smaller than the flexible side (low stiffness side). The difference in eccentricity affects clearly the inelastic floor rotation.Keywords: Eccentricity Stiffness, Pulse Ground Motion, Floor Rotation

A Study on an Inverse Estimation Method for Solving Soil-Structure Interaction System

2011 ◽  
Vol 255-260 ◽  
pp. 2891-2897
Author(s):  
Ming Hui Lee
Keyword(s):  
Ground Motion ◽  
Soil Structure ◽  
Direct Method ◽  
Estimation Method ◽  
Soil Structure Interaction ◽  
Structure Interaction ◽  
Interaction System ◽  
Inverse Estimation ◽  
The Difference ◽  
Stability And Accuracy

This paper describes a numerical algorithm to determine the responses of the soil-structure interaction system due to known ground motion acceleration. A ground motion acceleration of known magnitude was suddenly applied to the soil-structure interaction system by direct method and then utilized this displacement to estimate others relative displacements by a Kalman filter technique. In order to examine the accuracy of the proposed method, the difference material soil-structure system is subjected to the actual ground motion acceleration. The results show that this method has the advantages of stability and accuracy.

Relations between cell dimensions, chemical composition, and site preference of orthopyroxene

1969 ◽  
Vol 37 (285) ◽  
pp. 90-114 ◽  
Author(s):  
J. V. Smith ◽  
D. A. Stephenson ◽  
R. A. Howie ◽  
M. H. Hey
Keyword(s):  
Linear Regression Analysis ◽  
Physical Parameters ◽  
Site Preference ◽  
Mössbauer Studies ◽  
Minor Elements ◽  
Cell Dimensions ◽  
The Difference ◽  
Lower Site ◽  
Best Fit ◽  
Separate Regression

SummaryCell dimensions have been measured from correctly indexed powder patterns of thirty natural and two synthetic orthopyroxenes. The natural specimens (mostly metamorphic) contain exsolved phases largely avoided during microprobe chemical analysis. Linear regression analysis between the cell dimensions and Mg, Al, Ca contents (ignoring minor elements) was quite unsatisfactory until a term in Mg2 was added. Two separate regression analyses for the ranges Mg 0–0·5 and 0·5–1 using only Mg, Al, and Ca were satisfactory. Olivine yielded satisfactory regressions for the whole range without a term in Mg2 (Louisnathan and Smith, 1968). The difference between olivine and pyroxene results from absence of site preference by Mg and Fe in olivine compared to strong preference in pyroxene revealed by electron density and Mössbauer studies (Bancroft, Burns, and Howie, 1967; Ghose and Hafner, 1967).The data were recalculated by means of a new best-fit procedure developed by Hey in which the errors in the chemical and physical parameters are considered simultaneously.Earlier measurements of a and b for plutonic pyroxenes are consistent within possible experimental uncertainties with those given here; however a and b data obtained by Kuno and by Hess on volcanic specimens are considerably higher by variable amounts. Although there are uncertainties in the Ca content and its effect on a and b, the larger dimensions probably result from lower site preference as indicated by Mössbauer studies.Prediction of Mg, Ca, and Al from just the cell dimensions is only moderately accurate even for metamorphic orthopyroxenes.

Sign in / Sign up

Export Citation Format

Share Document