Article
Environmental Sciences
Dalia Munaff Naji, Muge K. Akin, Ali Firat Cabalar
Summary: This study presents a seismic site classification map for Kahramanmaras city in southern-central Turkey using geophysical tests, following NEHRP standards. The obtained data from field studies and measurements were used to describe subsurface conditions and classify seismic sites. The results show that the study area is predominantly categorized as soil site class C, with smaller areas classified as soil site class D and B.
ENVIRONMENTAL EARTH SCIENCES
(2021)
Article
Engineering, Geological
Paola Bordoni, Stefano Gori, Aybige Akinci, Francesco Visini, Sara Sgobba, Francesca Pacor, Fabrizio Cara, Stefano Pampanin, Giuliano Milana, Carlo Doglioni
Summary: This paper presents the ground response analyses of an industrial facility planned in an area located on an active normal fault system called the Mt. Morrone Fault system (MMF). The seismic input for the dynamic numerical analyses was assessed using an interdisciplinary and non-standard approach, incorporating geological, seismological, geotechnical, and engineering contributions. Scenario-based and probabilistic seismic hazard analyses were implemented, and nonlinear numerical simulations of seismic wave propagation were conducted. The results indicate that a scenario-based methodology can better capture the shaking effect in near-field conditions, providing a more robust approach for design and assessment of buildings.
ENGINEERING GEOLOGY
(2023)
Article
Geosciences, Multidisciplinary
Abul Aas, Satish Kumar Sinha
Summary: A seismic site characterization study was conducted in the south of the tectonically active Himalayan region using the MASW technique. The correlation between SPT-N and Vs was established to estimate shear wave velocity in the study area. The study provides important references for geotechnical engineering in areas with similar geological conditions.
JOURNAL OF APPLIED GEOPHYSICS
(2023)
Article
Engineering, Geological
Hazem Badreldin, Ahmed Abu El-Ata, Mahmoud El-Hadidy, Cecile Cornou, Abd el-aziz Khairy Abd el-aal, Amir Mahr Lala
Summary: This article examines the effect of geological characteristics on the propagation of seismic waves in Nuweiba. By using microtremor and surface wave data sets, the horizontal-to-vertical spectral ratio technique and Multichannel Analysis of Surface Waves are applied to determine parameters such as resonance frequency, bedrock depth, shear wave velocity structure, and transfer function. The study reveals that the geological features in Nuweiba play a significant role in amplifying seismic waves.
SOIL DYNAMICS AND EARTHQUAKE ENGINEERING
(2023)
Article
Engineering, Geological
Partha Sarathi Parhi, Umashankar Balunaini, Sasanka Mouli Sravanam
Summary: This study presents the characterization of dynamic properties of coal ash deposits through an extensive field experiment. The results show that the abandoned coal ash deposits have higher shear wave velocity than the active deposits. Additionally, a piecewise linear relationship between shear wave velocity and depth in active and abandoned coal ash deposits in India was identified based on this study and existing literature.
SOIL DYNAMICS AND EARTHQUAKE ENGINEERING
(2022)
Article
Engineering, Geological
Khalid Mahmood, Bakht Zamin, Shahid Iqbal, Zia-Ur-Rehman, Sher Afzal, Muhammad Safdar, Qaiser Iqbal, Arshad Ali
Summary: This study evaluates the impact of local site conditions on seismic hazard and provides improved and site-specific values of ground acceleration for the new Balakot town in Pakistan.
SOIL DYNAMICS AND EARTHQUAKE ENGINEERING
(2022)
Article
Geosciences, Multidisciplinary
Vincent Perron, Paolo Bergamo, Donat Fah
Summary: Empirical site response assessment is important for densely populated areas and facilities of special risk. The log-normal distribution is found to be a good approximation for site response, and a strategy to estimate the minimum number of earthquakes based on confidence intervals is developed. 10 uncorrelated earthquakes are determined to be the best compromise between minimizing the number of recordings and ensuring statistical significance of results.
FRONTIERS IN EARTH SCIENCE
(2022)
Article
Engineering, Geological
Jia-Cian Gao, Chung-Han Chan, Chyi-Tyi Lee
Summary: Utilizing a reservoir site in southern Taiwan as an example, this study implemented a novel approach to construct site-dependent ground-motion prediction equations, reducing uncertainties in ground-motion predictions and avoiding over-estimations in probabilistic seismic hazard analysis. By selecting ground-motion records with similar site conditions from nearby stations, a site-dependent GMPE set was created for crustal earthquakes in the region, showing significantly smaller scattering of residuals compared to existing regional GMPEs in Taiwan dataset, highlighting the potential for more accurate and reasonable prediction of ground-motion levels for infrastructure design and safety evaluation.
ENGINEERING GEOLOGY
(2021)
Article
Engineering, Geological
M. Anthi, N. Gerolymos
Summary: A numerical algorithm is developed for one-dimensional non-linear ground response analysis, capable of reproducing liquefaction and accounting for excess pore water pressure. The algorithm uses a plasticity constitutive model for sand, demonstrating versatility in representing complex cyclic behavior. The model is calibrated based on shear modulus reduction and damping curves, and is validated using seismic ground response data from the 1995 Kobe earthquake.
SOIL DYNAMICS AND EARTHQUAKE ENGINEERING
(2023)
Article
Engineering, Geological
Mohammad Talebi, Abbas Sivandi-Pour, Shamseddin Esmaeili, Mohammad Reza Soghrat, Hamidreza Safizadeh, Ehsan Ebrahimi, Mahdieh Akbarpoor, Rabe Sharifi Rad, Manoochehr Fallah, Ehsan Noroozinejad Farsangi
Summary: This study presents the spatial distribution of a grid-based probabilistic seismic hazard model at the surface level for the Kerman region in central-east Iran, using a hybrid site condition model. The model captures uncertainties of seismic hazard sources through a logic tree approach and demonstrates a wide range of seismic hazards in the region. In addition, various ground motion prediction equations have been evaluated for their compatibility with the studied area through statistical analyses.
SOIL DYNAMICS AND EARTHQUAKE ENGINEERING
(2022)
Article
Engineering, Geological
S. Fabozzi, S. Catalano, G. Falcone, G. Naso, A. Pagliaroli, E. Peronace, A. Porchia, G. Romagnoli, M. Moscatelli
Summary: The study focuses on analyzing the impact of Vs inversion on seismic site response in recurrent Italian geological domains, and its application in seismic microzonation studies. Common Italian geological domains with Vs profile inversions are identified, one-dimensional subsoil columns are defined for each domain, and numerical simulations are conducted to evaluate the influence of Vs inversion on ground shaking. Stochastic 1D analyses are carried out to consider variability in input parameters.
ENGINEERING GEOLOGY
(2021)
Article
Engineering, Environmental
R. Ramkrishnan, Sreevalsa Kolathayar, T. G. Sitharam
Summary: Region-specific GMPEs were used in a comprehensive seismic hazard analysis of the North and Central Himalayas, identifying vulnerable seismic sources based on the Seismotectonic Atlas. The study compiled an up-to-date earthquake catalogue from various sources since 250 BC and estimated Peak Ground Acceleration for individual seismic sources, showing higher PGA values compared to codal provisions for seismic zonation and design horizontal acceleration.
BULLETIN OF ENGINEERING GEOLOGY AND THE ENVIRONMENT
(2021)
Article
Engineering, Civil
Bo Li, Zhen Cai, Zhongdong Duan
Summary: In seismic risk analysis, selecting hazard-consistent ground motions is a key step. Current methods have limitations, and this study proposes a novel method that utilizes a scenario earthquake set and simulation of target response spectra. The selected ground motions using this method show very good consistency with the site seismic hazards.
Article
Geosciences, Multidisciplinary
Francisco J. Chavez-Garcia, Thulasiraman Natarajan, Martin Cardenas-Soto, Kusala Rajendran
Summary: Intense monsoon rains in 2018 triggered landslides in the Western Ghats region of India, causing significant damage. A case study on two landslides used seismic prospecting to characterize them, showing similar results with different analyses and correlations between shear-wave velocity distribution and seismic noise characteristics. The study suggests that soil thickness played a major role in the landslides' triggering.
Article
Geosciences, Multidisciplinary
Sankar Kumar Nath, Arpita Biswas, Anand Srivastava, Arnab Sengupta, Chitralekha Ghatak, Jyothula Madan
Summary: The Bengal Basin is a significant fluvio-deltaic to shallow marine sedimentary basin with high seismic hazard potential. The basin's geological features and fault networks have triggered many devastating earthquakes. By studying the geological and geophysical characteristics of the region in detail, seismic risk and potential damage can be assessed.
FRONTIERS IN EARTH SCIENCE
(2022)
Article
Engineering, Geological
Ketan Bajaj, P. Anbazhagan
BULLETIN OF EARTHQUAKE ENGINEERING
(2019)
Article
Geosciences, Multidisciplinary
Ketan Bajaj, P. Anbazhagan
JOURNAL OF APPLIED GEOPHYSICS
(2019)
Article
Geochemistry & Geophysics
P. Anbazhagan, A. Balakumar
JOURNAL OF SEISMOLOGY
(2019)
Article
Engineering, Civil
Ketan Bajaj, P. Anbazhagan
Summary: Site amplification coefficients and acceleration design response spectra (ADRS) for shallow sites in Southern India (SI) were derived through nonlinear site response analysis at 125 locations. New site factors and ADRS were proposed based on seismic hazard map and seismic site classification, and their compatibility with existing standards was evaluated.
JOURNAL OF EARTHQUAKE ENGINEERING
(2022)
Article
Engineering, Geological
D. R. Manohar, P. Anbazhagan
Summary: The shear strength characteristics of geosynthetic-reinforced rubber-sand mixture (RSM) were investigated by analyzing the size effect of rubber, different rubber content proportions, types and layers of geosynthetics, and their arrangement. The reinforced RSM showed enhanced strength and energy absorption capacity, as well as decreased brittleness index values.
GEOTEXTILES AND GEOMEMBRANES
(2021)
Article
Geosciences, Multidisciplinary
P. Anbazhagan, Mohammad Rafiq Joo, Meer Mehran Rashid, Nassir S. N. Al-Arifi
Summary: This paper studied site amplifications in the Indo-Gangetic Basin (IGB) at different depths, finding that some sites exhibited greater amplification at subsurface levels compared to surface levels, while a considerable number of sites showed less amplification at subsurface levels than at the surface.
Article
Engineering, Geological
Dhanaji Chavan, Thallak G. Sitharam, P. Anbazhagan
Summary: Desaturation of saturated sandy soils is an effective technique for liquefaction mitigation, with significantly higher cyclic strength and seismic performance compared to saturated sandy soils. By reducing the degree of saturation, the number of cycles required for initial liquefaction increases exponentially, and desaturated sandy soils can prevent liquefaction even during moderate to strong earthquakes with high peak ground acceleration. Different failure modes were observed in samples with varying degrees of saturation, with desaturated sandy soils performing better in resisting cyclic softening failures. Additionally, a modified pore pressure model has been proposed for predicting pore pressure evolution in desaturated sandy soils.
GEOTECHNICAL AND GEOLOGICAL ENGINEERING
(2022)
Article
Engineering, Geological
Ketan Bajaj, P. Anbazhagan
Summary: This study investigates the impact of input layer velocity or depth on surface response parameters and determines the appropriate layer for reliable estimation of these parameters through detailed site analysis.
GEOMECHANICS AND GEOENGINEERING-AN INTERNATIONAL JOURNAL
(2023)
Article
Engineering, Geological
Dhanaji Chavan, Thallak G. Sitharam, P. Anbazhagan
Summary: The study reveals that the failure modes of air desaturated clean sand in undrained cyclic loading vary depending on the degree of saturation, relative density, effective confining pressure, and cyclic shear stress ratio. The findings include hybrid cyclic liquefaction failure, gradual strain softening, cyclic mobility failure, and two types of cyclic softening failures with distinct phase transformation trends. Additionally, the critical state soil mechanics framework suggests that nearly saturated samples closest to the critical state tend to undergo cyclic mobility failure, while those farthest from the critical state fail by gradual strain softening.
INDIAN GEOTECHNICAL JOURNAL
(2022)
Article
Engineering, Geological
P. Anbazhagan, M. E. Yadhunandan, Ayush Kumar
Summary: Geotechnical investigation often involves using different SPT equipment in multiple boreholes in a single project without measuring the energy of the SPT hammer. This study measured the energy of the SPT hammer using two types of instrumented rods to understand its effects on rebound or termination criteria and safe bearing capacity estimation. The study found significant variations in energy results and suggested the need for revisiting SPT investigation practices, N correction, and SBC estimation in places where hammer energy is not measured.
INDIAN GEOTECHNICAL JOURNAL
(2022)
Article
Engineering, Geological
P. Anbazhagan, K. Panjami
Summary: This paper studies the effectiveness of different geophysical methods in detecting naturally formed subsurface cavities in lateritic deposits, and presents a comparative summary of various geophysical survey techniques used to identify the cavities. Geophysical techniques can easily detect the changes in physical properties between cavity space and surrounding medium.
INDIAN GEOTECHNICAL JOURNAL
(2023)
Article
Geochemistry & Geophysics
Ketan Bajaj, P. Anbazhagan
Summary: Seismic hazard in the Indo-Gangetic Basin has been analyzed through the computation of PGA and SA, with spatial estimation and the use of a layered seismogenic source model.
PURE AND APPLIED GEOPHYSICS
(2021)
Article
Engineering, Geological
Anbazhagan P. Panjamani, Sagar G. Ingale
Summary: SPT, as the most widely used field test, is not effectively regulated in India, leading to non-compliance with guidelines in field tests. Operational and equipment-related variables, such as hammer dimensions and blow rates, have been observed to vary significantly in field tests. Standardization of dimensions and normalization ofNvalues to a standard energy ratio are recommended to improve the reliability of SPT operations.
INDIAN GEOTECHNICAL JOURNAL
(2021)
Article
Engineering, Geological
P. Anbazhagan, Ketan Bajaj
INDIAN GEOTECHNICAL JOURNAL
(2020)
Article
Geosciences, Multidisciplinary
Panjamani Anbazhagan, Ketan Bajaj, Karanpreet Matharu, Sayed S. R. Moustafa, Nassir S. N. Al-Arifi
NATURAL HAZARDS AND EARTH SYSTEM SCIENCES
(2019)
