scholarly journals Liquefaction hazard zonation mapping of the Saitama City, Japan

2010 ◽  
Vol 40 ◽  
pp. 69-76 ◽  
Author(s):  
Rama Mohan Pokhrel ◽  
Jiro Kuwano ◽  
Shinya Tachibana
Keyword(s):  
Shear Wave ◽  
Wave Velocity ◽  
Shear Wave Velocity ◽  
Hazard Zonation ◽  
Liquefaction Potential ◽  
Amplification Ratio ◽  
Liquefaction Hazard ◽  
Clayey Silt ◽  
The City ◽  
Very High

Liquefaction hazard zonation mapping of the Saitama City targeted on the Kanto Plain NW Edge Fault is described in this paper. The study involves the geotechnical properties of the alluvial soil of the city including Standard Penetration Test (SPT), shear wave velocity and other geological data analysis. The city being highly urbanized is situated on the soft soil (alluvial deposits) at the proximity of an active seismic fault that has increased the possibility of liquefaction hazard in the area. Kanto Plain NW Edge Fault is an active fault that lies very near to the Saitama City having the estimated possible earthquake magnitude of 7.4. The possible peak horizontal ground acceleration (amax) from this earthquake is calculated as from 0.15 g to 0.30 g. By considering all possible acceleration values the liquefaction potential maps were prepared and presented in this paper. Additionally, the shear wave velocity is very low and amplification ratio is very high at the marshy deposit but it has comparatively high velocity and low amplification ratio at the marine loam deposit area of the Omiya Plateau. In this paper the liquefaction potential of the area is expressed in terms of liquefaction potential index (PL). The PL value for the clayey silt deposit in the marshy area with shallow water table is very high. In addition, the PL value in the marine loam deposit of the Omiya Plateau is less which indicates that loam deposit has less liquefaction potential than marshy deposit. The map obtained from this study was validated with the field condition of the study area. Hence, it is expected that this study will assist in characterizing the seismic hazards and its mitigation and will provide valuable information for urban planning in the study area in future.

scholarly journals Investigation of Soil Liquefaction Potential around Efteni Lake in Duzce Turkey: Using Empirical Relationships between Shear Wave Velocity and SPT Blow Count (N)

2014 ◽  
Vol 2014 ◽  
pp. 1-15
Author(s):  
Ali Ateş ◽  
İnan Keskin ◽  
Ermedin Totiç ◽  
Burak Yeşil
Keyword(s):  
Shear Wave ◽  
Wave Velocity ◽  
Shear Wave Velocity ◽  
Standard Penetration Test ◽  
Penetration Test ◽  
Empirical Relationships ◽  
Liquefaction Potential ◽  
Liquefaction Potential Index ◽  
Potential Index ◽  
The City

Evaluation of the liquefaction potential of a liquefaction-prone area is important for geotechnical earthquake engineering, both for assessment for site selection and for planning and new constructions. The liquefaction potential index for the city of Duzce in northwestern Turkey using the empirical relationships between the Standard Penetration Test (SPT) and the Shear Wave Velocity Test (VS) was investigated in this study. After,VSvalues based on SPT blow counts (N) were obtained from the alluvial soils in the city of Duzce. The liquefaction potential indexes of the soils were determined using the empirical relationships between the Standard Penetration Test (SPT) and the Shear Wave Velocity Test (VS) calculating for a probable earthquake ofMW=7.2. In the result of the study, the liquefaction potential index (LPI) values were interpreted and compared evaluating the SPTNblow count values obtained from the study area. Based on the empirical relationships assumed for the soils, it was observed that there was not a perfect agreement between the results of the two methods. The liquefaction potential index values using the SPTNblow counts were found to be lower than those of theVSmethod.

Soil Liquefaction Evaluation of Offshore Site Based on In Situ Shear Wave Velocity Measurements

2013 ◽  
Vol 405-408 ◽  
pp. 470-473
Author(s):  
Sheng Jie Di ◽  
Ming Yuan Wang ◽  
Zhi Gang Shan ◽  
Hai Bo Jia
Keyword(s):  
Shear Wave ◽  
Wave Velocity ◽  
Shear Wave Velocity ◽  
Wind Farm ◽  
Soil Liquefaction ◽  
Offshore Wind ◽  
Velocity Measurements ◽  
Liquefaction Resistance ◽  
Liquefaction Potential

A procedure for evaluating liquefaction resistance of soils based on the shear wave velocity measurements is outlined in the paper. The procedure follows the general formal of the Seed-Idriss simplified procedure. In addition, it was developed following suggestions from industry, researchers, and practitioners. The procedure correctly predicts moderate to high liquefaction potential for over 95% of the liquefaction case histories. The case study for the site of offshore wind farm in Jiangsu province is provided to illustrate the application of the proposed procedure. The feature of the soils and the shear wave velocity in-situ tested in site are discussed and the liquefaction potential of the layer is evaluated. The application shows that the layers of the non-cohesive soils in the depths 3-11m may be liquefiable according to the procedure.

scholarly journals Evaluation of liquefaction potentials based on shear wave velocities in Pohang City, South Korea

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Yumin Ji ◽  
Byungmin Kim ◽  
Kiseog Kim
Keyword(s):  
South Korea ◽  
Shear Wave ◽  
Wave Velocity ◽  
Shear Wave Velocity ◽  
Ground Surface ◽  
Velocity Profiles ◽  
Liquefaction Potential ◽  
Attenuation Relationships ◽  
Cyclic Resistance ◽  
Sand Boils

AbstractThis study evaluates the potentials of liquefaction caused by the 2017 moment magnitude 5.4 earthquake in Pohang City, South Korea. We obtain shear wave velocity profiles measured by suspension PS logging tests at the five sites near the epicenter. We also perform downhole tests at three of the five sites. Among the five sites, the surface manifestations (i.e., sand boils) were observed at the three sites, and not at the other two sites. The maximum accelerations on the ground surface at the five sites are estimated using the Next Generation Attenuation relationships for Western United State ground motion prediction equations. The shear wave velocity profiles from the two tests are slightly different, resulting in varying cyclic resistance ratios, factors of safety against liquefaction, and liquefaction potential indices. Nevertheless, we found that both test approaches can be used to evaluate liquefaction potentials. The liquefaction potential indices at the liquefied sites are approximately 1.5–13.9, whereas those at the non-liquefied sites are approximately 0–0.3.

Shear Wave Velocity of a Compacted Clayey Silt

2007 ◽  
Vol 30 (5) ◽  
pp. 100655 ◽  
Author(s):  
L. D. Suits ◽  
T. C. Sheahan ◽  
Juan J. Clariá ◽  
Víctor A. Rinaldi
Keyword(s):  
Shear Wave ◽  
Wave Velocity ◽  
Shear Wave Velocity ◽  
Clayey Silt

Seismic cone penetration test for evaluating liquefaction potential under cyclic loading

1992 ◽  
Vol 29 (4) ◽  
pp. 686-695 ◽  
Author(s):  
P. K. Robertson ◽  
D. J. Woeller ◽  
W. D. L. Finn
Keyword(s):  
Cyclic Loading ◽  
Shear Wave ◽  
Wave Velocity ◽  
Shear Wave Velocity ◽  
Penetration Resistance ◽  
Penetration Test ◽  
Cone Penetration ◽  
Liquefaction Potential ◽  
A Site ◽  
Seismic Cone Penetration Test

Impressive progress has been made in the last 25 years in recognizing liquefaction hazards, understanding liquefaction phenomena, and analyzing and evaluating the potential for liquefaction at a site. Recent findings related to the application of the seismic cone penetration test (SCPT) for the evaluation of liquefaction potential under cyclic loading are presented and discussed. The SCPT provides independent measurements of penetration resistance, pore pressures, and shear-wave velocity in a fast, continuous, and economic manner. The current methods available for evaluating liquefaction using penetration resistance are presented and discussed. Recent developments in the application of shear-wave velocity to evaluate liquefaction potential are discussed, and a new method based on normalized shear-wave velocity is proposed. Limited case-history data are used to evaluate and support the proposed correlation. A worked example is presented to illustrate the potential usefulness of the SCPT for evaluating liquefaction potential at a site. Key words : liquefaction, in situ tests, seismic.

scholarly journals Lithological modelling based on shear wave velocity using horizontal to vertical spectral ratio (HVSR) inversion of ellipticity curve method to mitigate landslide hazards at the main road Of Samigaluh District, Kulon Progo Regency, Yogyakarta

2021 ◽  
Vol 325 ◽  
pp. 01009
Author(s):  
Skolastika Novita Widyadarsana ◽  
Eddy Hartantyo
Keyword(s):  
Shear Wave ◽  
Wave Velocity ◽  
Shear Wave Velocity ◽  
Spectral Ratio ◽  
Main Road ◽  
Landslide Hazards ◽  
Landslide Mitigation ◽  
Curve Method ◽  
Hvsr Technique ◽  
The City

Many landslides occur in Samigaluh District, Kulon Progo Regency, Yogyakarta, Indonesia. However, no research discusses landslides that often occur on the main road connecting the city of Yogyakarta and various tourist resorts in Samigaluh. This study aims at determining the soil vulnerability and lithology model at that main road as a contribution to landslide mitigation planning. This lithology model is based on shear wave velocity (Vs) and layer thickness derived by microtremor datasets. The data were processed by the inversion of the Horizontal to Vertical Spectral Ratio (HVSR) technique of the ellipticity curve method. The result of the study shows that the first layer is associated with topsoil which has Vs of 263 m/s, the second layer is clay which has Vs of 607 m/s, the third layer consists of clay, breccia, and pumice which has Vs of 1119 m/s, and the fourth layer is andesite bedrock which has Vs of 1721 m/s. Andesite is impermeable to water and can become a slip field for landslides. Clay, breccias, and pumice can absorb water so that their weight increases when it rains. When they are on an impermeable rock on a certain slope, a landslide occurs.

ESTIMATION OF SHEAR-WAVE VELOCITY STRUCTURE USING MICROTREMOR MEASUREMENTS

2019 ◽  
Vol 6 (1) ◽  
Author(s):  
Zorigt Tumurbaatar ◽  
Hiroyuki Miura
Keyword(s):  
Shear Wave ◽  
Wave Velocity ◽  
Shear Wave Velocity ◽  
Urban Areas ◽  
Velocity Structure ◽  
Earthquake Hazard ◽  
Site Amplification ◽  
Spectral Ratios ◽  
Inversion Analysis ◽  
The City

Due to the recent construction boom in Ulaanbaatar city (UB), Mongolia, newly urban areas are rapidly expanded to the surrounded area of the city. According to the previous researches and reports, the thickness of the sedimentary basin in UB reaches 120m at the maximum in the area along the Tuul river. Therefore, the evaluation of site amplification is one of the essential parts of the estimation of earthquake hazard in this area. In this paper, the shear-wave velocity (Vs) structures in UB are estimated from single microtremor observations with the existing microtremor array observations. We carried out the microtremor observations at 50 sites and computed horizontal-to-vertical (H/V) spectral ratios. Inversion analysis is performed to the observed H/V spectral ratios based on the diffuse field approach (DFA) to determine the Vs structures. The site characterizations are evaluated from the amplification factors of the Vs structures.

Sign in / Sign up

Export Citation Format

Share Document