Liquefaction Potential for Kolkata City

2013 ◽  
Vol 4 (2) ◽  
pp. 18-33 ◽  
Author(s):  
Ravi Sankar Jakka ◽  
Amit Shiuly ◽  
Ranjit Das
Keyword(s):  
Factor Of Safety ◽  
Alluvial Soil ◽  
Seismic Demand ◽  
Soil Resistance ◽  
Liquefaction Potential ◽  
Soil Layers ◽  
Ground Shaking ◽  
Large Thickness ◽  
Soil Deposits ◽  
Kolkata City

This paper presents the liquefaction potential of densely populated Kolkata city, which is situated on the world's largest delta island with very soft and thick alluvial soil deposits. Due to presence of soft alluvium deposits at shallow depths, soil resistance against liquefaction is expected to be less. Additionally, large thickness of soil layers may amplify the ground shaking resulting in high seismic demand on the soil. Here in this study, variation of factor of safety against liquefaction is evaluated with depth at different locations in Kolkota city. The study founds striking results that the Kolkata city soils are less prone to liquefaction even though there is significant ground amplification due to presence of thick soil deposits.

scholarly journals Ecological Assessment of Alluvial Soil Resistance to Anthropogenic Impact

2021 ◽  
Vol 666 (6) ◽  
pp. 062147
Author(s):  
L P Stepanova ◽  
N A Yelizarov ◽  
A V Pisareva
Keyword(s):  
Anthropogenic Impact ◽  
Alluvial Soil ◽  
Ecological Assessment ◽  
Soil Resistance

Simple approach to obtain ground amplification motion of surface soil deposits with a radical change of depth

2005 ◽  
Vol 42 (2) ◽  
pp. 491-498
Author(s):  
Dae-Sang Kim ◽  
Kazuo Konagai
Keyword(s):  
Seismic Design ◽  
Surface Soil ◽  
Underground Structure ◽  
Free Field ◽  
Alluvial Soil ◽  
Radical Change ◽  
Simple Approach ◽  
Clear Understanding ◽  
Underground Structures ◽  
Soil Deposits

Earthquake observations at different sites within alluvial soil deposits have demonstrated that the motion of buried underground structures closely follows that of the surrounding soil. Therefore, it is usual in a seismic design process to apply free-field ground displacements through Winkler-type soil springs to an underground structure to evaluate stress patterns induced within its structural members. Using a simplified approach, this paper provides a clear understanding of resonant horizontal ground displacement of and strain in a surface soil deposit with a radical change of depth and of where they occur.Key words: simple approach, seismic design, earthquake, resonance, underground structures.

scholarly journals Evaluation of Pigeon Pea Lines for Biological Soil Decompaction

2009 ◽  
Vol 2009 ◽  
pp. 1-7
Author(s):  
Rodolfo Godoy ◽  
Osny Oliveira Santos Bacchi ◽  
Fernando Almeida Moreira ◽  
Klaus Reichardt
Keyword(s):  
Root Growth ◽  
Pigeon Pea ◽  
Soil Resistance ◽  
Biological Processes ◽  
Soil Layers ◽  
Compacted Soil ◽  
Cultivation Practices ◽  
Series Of Experiments ◽  
Growth Development ◽  
Resistance To Penetration

Soil decompaction is generally achieved through mechanical cultivation practices; however biological processes can significantly add to this process through root growth, development, and later senescence. This study was carried out in Piracicaba, SP, Brazil and had the purpose of selecting, among forty one pure pigeon pea lines, the most efficient genotypes that promote soil decompaction by roots penetrating compacted soil layers. Utilizing artificially compacted 30 mm high soil blocks, in a series of experiments, these lines were compared to the cultivar Fava Larga taken as a standard. Three lines were preliminarily selected out of the initial group, and afterwards, in more detailed screenings by monitoring soil resistance to penetration and also evaluating the behavior of Tanzania grass plants seeded after pigeon pea, two of them, g5-94 and g8-95, were selected as possessing the most fit root system to penetrate compacted soil layers.

Liquefaction Susceptibility Assessment Using Geotechnical and Geological Manners of Northern Thailand

2020 ◽  
Vol 11 (2) ◽  
pp. 50-71
Author(s):  
Yayat Kusumahadi ◽  
Suttisak Soralump ◽  
Montri Jinagoolwipat
Keyword(s):  
Spectral Analysis ◽  
Groundwater Table ◽  
Soil Resistance ◽  
Susceptibility Assessment ◽  
Liquefaction Potential ◽  
Liquefaction Susceptibility ◽  
Site Investigations ◽  
Geological Formation ◽  
Soil Site ◽  
High Seismicity

Soil site investigations such as boring logs, basic soil properties, spectral analysis of surface wave, and the examinations of geologic and geomorphologic were performed in Mae Lao area to investigate the susceptibility of liquefaction after the 6.2 Mw Chiang Rai Earthquake 2014. The study area was found to lay on a complex geological formation and geotechnical behavior with a condition of the high groundwater table. Being located on a high seismicity area (intensity V-VII Mercalli) governs the study area as a concern for high liquefaction hazards. Liquefaction susceptibility-based compositional criteria, soil resistance, and geologic criteria have been established, and consequently, the character of liquefaction potential is defined.

scholarly journals Probabilistic version of the Robertson and Wride method for liquefaction evaluation: development and application

2012 ◽  
Vol 49 (1) ◽  
pp. 27-44 ◽  
Author(s):  
Chih-Sheng Ku ◽  
C. Hsein Juang ◽  
Chi-Wen Chang ◽  
Jianye Ching
Keyword(s):  
Factor Of Safety ◽  
Probabilistic Models ◽  
Deterministic Model ◽  
Soil Liquefaction ◽  
Penetration Test ◽  
Cone Penetration ◽  
Liquefaction Potential ◽  
Additional Information ◽  
Extra Effort ◽  
Probabilistic Version

The Robertson and Wride method is the most widely used cone penetration test (CPT)-based method for soil liquefaction evaluation. This method is a deterministic model, which expresses liquefaction potential in terms of factor of safety. On many occasions, there is a need to express the liquefaction potential in terms of liquefaction probability. Although several probabilistic models are available in the literature, there is an advantage having a probabilistic version of the Robertson and Wride method so that the engineer who prefers to use this method can obtain additional information of liquefaction probability with minimal extra effort. In this paper, a simple model is developed, which links the factor of safety determined by the Robertson and Wride method to the liquefaction probability. The model, referred to as the probabilistic RW model, is developed, and verified, in a mathematically rigorous manner. Simplified equations for assessing the variation of liquefaction probability caused by the uncertainty in input parameters are also developed. Example applications are presented to demonstrate the developed models.

Evaluation of liquefaction potential of soil deposits using artificial neural networks

2007 ◽  
Vol 24 (1) ◽  
pp. 5-16 ◽  
Author(s):  
Adel M. Hanna ◽  
Derin Ural ◽  
Gokhan Saygili
Keyword(s):  
Neural Networks ◽  
Artificial Neural Networks ◽  
Liquefaction Potential ◽  
Soil Deposits ◽  
Artificial Neural

scholarly journals Soil liquefaction potential in Eskişehir, NW Turkey

2011 ◽  
Vol 11 (4) ◽  
pp. 1071-1082 ◽  
Author(s):  
H. Tosun ◽  
E. Seyrek ◽  
A. Orhan ◽  
H. Savaş ◽  
M. Türköz
Keyword(s):  
Ground Water ◽  
Management Practices ◽  
Alluvial Soil ◽  
Experimental Studies ◽  
Standard Penetration Test ◽  
Soil Liquefaction ◽  
Water Levels ◽  
Liquefaction Potential ◽  
Geotechnical Investigations ◽  
Nw Turkey

Abstract. Liquefaction is one of the critical problems in geotechnical engineering. High ground water levels and alluvial soils have a high potential risk for damage due to liquefaction, especially in seismically active regions. Eskişehir urban area, studied in this article, is situated within the second degree earthquake region on the seismic hazard zonation map of Turkey and is surrounded by Eskişehir, North Anatolian, Kütahya and Simav Fault Zones. Geotechnical investigations are carried out in two stages: field and laboratory. In the first stage, 232 boreholes in different locations were drilled and Standard Penetration Test (SPT) was performed. Test pits at 106 different locations were also excavated to support geotechnical data obtained from field tests. In the second stage, experimental studies were performed to determine the Atterberg limits and physical properties of soils. Liquefaction potential was investigated by a simplified method based on SPT. A scenario earthquake of magnitude M=6.4, produced by Eskişehir Fault Zone, was used in the calculations. Analyses were carried out for PGA levels at 0.19, 0.30 and 0.47 g. The results of the analyses indicate that presence of high ground water level and alluvial soil increase the liquefaction potential with the seismic features of the region. Following the analyses, liquefaction potential maps were produced for different depth intervals and can be used effectively for development plans and risk management practices in Eskişehir.

scholarly journals Liquefaction Potential Analysis in Bucharest City as a Result of the Ground Shaking during Strong Vrancea Earthquakes

2021 ◽  
Vol 8 (2) ◽  
pp. 113-138
Author(s):  
ANDREI BALA ◽  
DIETER HANNICH
Keyword(s):  
Lateral Spreading ◽  
German Research Foundation ◽  
Liquefaction Potential ◽  
Strong Earthquakes ◽  
Ground Shaking ◽  
Vrancea Earthquakes ◽  
Liquefaction Hazard ◽  
Institute Of Technology ◽  
The University ◽  
Bucharest City

Bucharest, the capital of Romania with about 2.5 million inhabitants, is frequently struck by intense, damaging earthquakes (2–3 events per century). The Collaborative Research Center 461 (CRC-461) entitled: “Strong Earthquakes - a Challenge of Geosciences and Civil Engineering” was established in July 1996 and ended in December 2007, but some projects continued until 2010. It was funded by the German Research Foundation and involved the University of Karlsruhe which today belongs to Karslruhe Institute of Technology. The CRC aimed strategic research in the field of strong earthquakes with regional focus on the Vrancea seismic events in Romania. Between 1995–2007 several research works were done in Romania, with the support of several Romanian research institutes and the University of Bucharest. One of the research questions was to study the occurring of liquefaction during strong earthquakes within the shallow sandy layers in Bucharest. In suitable conditions, strong earthquakes can cause, under certain geologic conditions, liquefaction and therewith ground failure as sand boils, lateral spreading, or differentiated subsidence. In the present paper we analyze the liquefaction risk for Bucharest. For this purpose, at 10 representative sites in Bucharest, Seismic Cone Penetration Tests (SCPTu) were executed. An area-wide evaluation of the liquefaction probability in Bucharest was established. The factor of safety (FS) against liquefaction and the probability of liquefaction (PL) were computed from the obtained test-data. For the first time, maps of the liquefaction potential index (Li) for Bucharest were outlined. This map shows how severe the liquefaction phenomena might be during strong Vrancea earthquakes in Bucharest, amplifying the site effects. Keywords: hydrogeologic conditions, liquefaction probability, liquefaction hazard, Bucharest city, strong Vrancea earthquakes

Sign in / Sign up

Export Citation Format

Share Document