This document compares the Back-Propagation (BPNN) and General Regression (GRNN) neural network architectures for analyzing soil liquefaction using simplified penetration test (SPT) data. It analyzes 157 liquefaction cases using these two architectures to evaluate which performs better. The results found that cyclic resistance ratio, cyclic stress ratio, corrected SPT blow count, and earthquake magnitude were the most important parameters for predicting liquefaction. The GRNN model results closely matched those of an existing simplified method. Therefore, the document recommends using the developed GRNN model for easier and faster liquefaction analysis.
Indoor wintertime PM1 levels were measured in a university building in Zagreb, Croatia to investigate the relationship between indoor particulate matter and outdoor meteorological conditions. 1-minute PM1 concentrations were measured at ground and first floor levels using two light-scattering laser photometers. Outdoor meteorological data were also collected. Results showed indoor PM1 levels depended most strongly on outdoor air temperature and relative humidity, with response times ranging from 1.2 to 2.7 hours/days. Elevated indoor PM1 likely originated from an industrial zone 8-9 km away. Both indoor PM1 and meteorological data exhibited semidiurnal, diurnal, and 10-11 day periodicities, with PM1 possibly associated
Limitations of simplified methods for estimating seismic settlements 12dRobert Pyke
Updated and expanded version of my technical note on estimating earthquake-induced settlements due to compaction. Notes limitations of existing simplified methods and suggest an improved screening methodology as well as a much improved method of analysis.
Terra Seismic can predict most major earthquakes (M6.2 or greater) at least 2 - 5 months before they will strike. Global earthquake prediction is based on determinations of the stressed areas that will start to behave abnormally before
major earthquakes. The size of the observed stressed areas roughly corresponds to estimates calculated from Dobrovolsky’s formula. To identify abnormalities and make predictions, Terra Seismic applies various methodologies, including satellite remote sensing methods and data from ground-based
instruments. We currently process terabytes of information daily, and use more than 80 different multiparameter prediction systems. Alerts are issued if the abnormalities are confirmed by at least five different systems. We observed that geophysical patterns of earthquake development and stress accumulation
are generally the same for all key seismic regions. Thus, the same earthquake prediction methodologies and systems can be applied successfully worldwide. Our technology has been used to retrospectively test data gathered since 1970 and it successfully detected about 90 percent of all significant quakes over the last 50 years.
Low-Level Wind Variability over the Indochina Peninsula during Boreal Wintersooktawee
This document summarizes a study on low-level wind variability over the Indochina Peninsula during the boreal winter. Vector empirical orthogonal function (VEOF) analysis was used to decompose wind data into spatial and temporal modes. The first two modes accounted for over 60% of the total variance. Composite analysis showed stronger northeasterly winds during the positive phase and stronger southwesterly winds during the negative phase. Correlations between the first principal component and East Asian winter monsoon indices were weak, suggesting other climate factors may also influence low-level winds over the region.
Pyke paper for asce lifelines conference 2021 22Robert Pyke
This is the final draft of a paper submitted to the ASCE Lifelines Conference 2021 (to be held at UCLA in 2022), which in part commemorates the 50th anniversary of the 1971 San Fernando earthquake. It summarizes observations of earthquake-induced settlements at the Joseph Jensen Filtration Plant and how these observations prompted more detailed studies of the mechanism of such settlements.
MODERNIZATION OF THE CLASSICAL SCHEME OF THE HANDICRAFT MANUFACTURE OF SOIL P...IAEME Publication
This document discusses the modernization of handicraft soil pressure sensors. Traditional sensors often failed due to contact breakdown, depressurization, or short circuits. The authors propose upgrades to minimize failure, including fiberglass boards, two-stage sealing with epoxy resin, stronger titanium bodies, and different adhesives and cables. Laboratory tests of upgraded sensors in soil samples showed no failures and measurement errors below 10%. However, attempts to create handicraft pore pressure sensors resulted in failures when soil entered through holes in the sensor body.
The International Journal of Engineering and Science (The IJES)theijes
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
The papers for publication in The International Journal of Engineering& Science are selected through rigorous peer reviews to ensure originality, timeliness, relevance, and readability.
Indoor wintertime PM1 levels were measured in a university building in Zagreb, Croatia to investigate the relationship between indoor particulate matter and outdoor meteorological conditions. 1-minute PM1 concentrations were measured at ground and first floor levels using two light-scattering laser photometers. Outdoor meteorological data were also collected. Results showed indoor PM1 levels depended most strongly on outdoor air temperature and relative humidity, with response times ranging from 1.2 to 2.7 hours/days. Elevated indoor PM1 likely originated from an industrial zone 8-9 km away. Both indoor PM1 and meteorological data exhibited semidiurnal, diurnal, and 10-11 day periodicities, with PM1 possibly associated
Limitations of simplified methods for estimating seismic settlements 12dRobert Pyke
Updated and expanded version of my technical note on estimating earthquake-induced settlements due to compaction. Notes limitations of existing simplified methods and suggest an improved screening methodology as well as a much improved method of analysis.
Terra Seismic can predict most major earthquakes (M6.2 or greater) at least 2 - 5 months before they will strike. Global earthquake prediction is based on determinations of the stressed areas that will start to behave abnormally before
major earthquakes. The size of the observed stressed areas roughly corresponds to estimates calculated from Dobrovolsky’s formula. To identify abnormalities and make predictions, Terra Seismic applies various methodologies, including satellite remote sensing methods and data from ground-based
instruments. We currently process terabytes of information daily, and use more than 80 different multiparameter prediction systems. Alerts are issued if the abnormalities are confirmed by at least five different systems. We observed that geophysical patterns of earthquake development and stress accumulation
are generally the same for all key seismic regions. Thus, the same earthquake prediction methodologies and systems can be applied successfully worldwide. Our technology has been used to retrospectively test data gathered since 1970 and it successfully detected about 90 percent of all significant quakes over the last 50 years.
Low-Level Wind Variability over the Indochina Peninsula during Boreal Wintersooktawee
This document summarizes a study on low-level wind variability over the Indochina Peninsula during the boreal winter. Vector empirical orthogonal function (VEOF) analysis was used to decompose wind data into spatial and temporal modes. The first two modes accounted for over 60% of the total variance. Composite analysis showed stronger northeasterly winds during the positive phase and stronger southwesterly winds during the negative phase. Correlations between the first principal component and East Asian winter monsoon indices were weak, suggesting other climate factors may also influence low-level winds over the region.
Pyke paper for asce lifelines conference 2021 22Robert Pyke
This is the final draft of a paper submitted to the ASCE Lifelines Conference 2021 (to be held at UCLA in 2022), which in part commemorates the 50th anniversary of the 1971 San Fernando earthquake. It summarizes observations of earthquake-induced settlements at the Joseph Jensen Filtration Plant and how these observations prompted more detailed studies of the mechanism of such settlements.
MODERNIZATION OF THE CLASSICAL SCHEME OF THE HANDICRAFT MANUFACTURE OF SOIL P...IAEME Publication
This document discusses the modernization of handicraft soil pressure sensors. Traditional sensors often failed due to contact breakdown, depressurization, or short circuits. The authors propose upgrades to minimize failure, including fiberglass boards, two-stage sealing with epoxy resin, stronger titanium bodies, and different adhesives and cables. Laboratory tests of upgraded sensors in soil samples showed no failures and measurement errors below 10%. However, attempts to create handicraft pore pressure sensors resulted in failures when soil entered through holes in the sensor body.
The International Journal of Engineering and Science (The IJES)theijes
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
The papers for publication in The International Journal of Engineering& Science are selected through rigorous peer reviews to ensure originality, timeliness, relevance, and readability.
This paper presents a comprehensive liquefaction potential assessment for the ground conditions in Hong Kong's North-west New Territories region. One-dimensional site response analyses were carried out to calculate cyclic shear stresses for 27 soil profiles from boreholes. Two input earthquake ground-motion levels corresponding to a 10% and 2% chance of exceedance in the next 50 years were examined. The results show the chance of liquefaction for the 10% motion is very low, but some soils may liquefy under the more extreme 2% motion. Published geological maps and over 3000 boreholes were used to develop liquefaction microzonation maps. A comparison was also made between the findings and liquefaction likelihood defined in China's Seismic Code.
Time-History Analysis on Seismic Stability of Nuclear Island Bedrock with wea...ijceronline
This paper presents a three-dimensional numerical simulation method for the seismic response calculation of nuclear island foundation based on the nuclear power plant in Tai Shan. There are two weak interlayers in the bedrock. The numerical simulation aimed at the analysis and the evaluation of the stability of bedrock with the consideration of the interaction between the bedrock and nuclear island. Main features of nuclear numerical model are: (1) the mechanical interaction of nuclear island buildings, turbine room and bedrock have been taken into consideration, (2) the two weak interlayers may decrease the stability of the bedrock, which are the focused research in the models, (3) non-reflective free field boundary have been used in the boundary condition of model. The commercial numerical software FLAC3D has also been used in the simulation and analysis. A finite difference of numerical model for nuclear island bedrock was established and it have been used to analyze the bedrock’s mechanical phenomenon and safety performance. Dynamic characteristics, distributions of mechanical parameters and failure characteristics of bedrock have been studied under the action of seismic wave.
Parametric analysis of ground temperature profile in bwari north central nigeriaAlexander Decker
This study analyzed ground temperature data collected over five years in Bwari, Nigeria to predict future climate changes and natural disasters. The results showed that net earth radiation has increased and rainfall has not been able to offset it. May typically had the highest average monthly ground temperatures. 2012 experienced major flooding in Nigeria. While 2013 may see increased solar radiation, reduced flooding is predicted; heavier flooding may occur in 2014 or 2015 due to the continued rise in net earth radiation not being balanced by natural forces.
This study estimates local site effects in the Ataköy area of Istanbul, Turkey through multiple techniques. A hybrid 3D finite-difference method is used to model site amplification from a scenario earthquake using a 3D velocity model of the local geology. Horizontal-to-vertical spectral ratios are calculated from microtremor recordings at 30 sites and compared to synthetic noise data from a 1D geological model. The results indicate the strongest amplifications around 1 Hz, with alluvial sites expected to experience amplification factors of 1.5-2. Comparing the different methods provides a comprehensive understanding of site effects in this densely populated and seismically hazardous area of Istanbul.
A Review of Change Detection Techniques of LandCover Using Remote Sensing Dataiosrjce
IOSR Journal of Computer Engineering (IOSR-JCE) is a double blind peer reviewed International Journal that provides rapid publication (within a month) of articles in all areas of computer engineering and its applications. The journal welcomes publications of high quality papers on theoretical developments and practical applications in computer technology. Original research papers, state-of-the-art reviews, and high quality technical notes are invited for publications.
This document summarizes a study that evaluated liquefaction potential in Babol City, Iran using both deterministic and probabilistic approaches. Over 600 soil borehole records from 60 sites were analyzed using 4 deterministic methods (including Seed) and 1 probabilistic reliability method. Microzonation maps identified liquefaction and non-liquefaction areas for each method. Results showed the reliability approach provided an accurate assessment of liquefaction potential. A 2D boundary line was also developed using (CSR) and (Nspt) parameters to identify liquefaction/non-liquefaction areas based on safety factors and probability. The study aims to assess liquefaction potential in Babol City and determine the most valid approach.
Naghizadehrokni et al-2018-geoenvironmental_disastersMehran Naghizadeh
This document summarizes a study that evaluated liquefaction potential in Babol City, Iran using both deterministic and probabilistic approaches. Over 600 soil borehole records from 60 sites across the city were analyzed using 4 deterministic methods (including Seed's method) and 1 probabilistic reliability method. Microzonation maps showed liquefaction and non-liquefaction areas from each method. The reliability approach was found to accurately assess liquefaction potential. A 2D boundary line was also developed from the data to identify liquefaction/non-liquefaction based on cyclic stress ratio and SPT resistance. The maps and boundary line produced can help identify liquefaction risk in Babol City.
Makalah ini membahas sejarah perkembangan web mulai dari penemuan teknologi web oleh Tim Berners-Lee di CERN hingga perkembangan browser dan standar-standar web."
Este documento presenta una introducción a la gerencia de proyectos de tecnología educativa. Explica que la gerencia de proyectos implica ejecutar actividades de manera temporal para crear un producto, servicio o resultado único, y requiere tomar decisiones, lograr objetivos y administrar recursos. También describe las características, el ciclo de vida, las fases y herramientas de un proyecto, así como los diferentes interesados que pueden afectarlo positiva o negativamente. El propósito es ofrecer una visión general de los
Dokumen tersebut membahas tentang perkembangan motorik pada anak usia 0-6 tahun. Ia menjelaskan tahapan-tahapan perkembangan motorik kasar dan halus pada setiap kelompok usia, mulai dari bayi hingga anak usia sekolah dasar. Tujuannya adalah agar dapat memahami perkembangan motorik yang sesuai pada setiap tahap usia anak.
Endo perio lesions /certified fixed orthodontic courses by Indian dental aca...Indian dental academy
The Indian Dental Academy is the Leader in continuing dental education , training dentists in all aspects of dentistry and offering a wide range of dental certified courses in different formats.
This document contains schedules for the Deontología Jurídica 40 course taught by JORJE LUIS GOMEZ on various dates in 2015 and 2016. It lists the time slots and instructor Lady García.
We represent the rights of people with personal injuries caused in auto accidents and other negligence. We help and represent people who wish to file bankruptcy or are suffering from creditor harassment.
This paper presents a comprehensive liquefaction potential assessment for the ground conditions in Hong Kong's North-west New Territories region. One-dimensional site response analyses were carried out to calculate cyclic shear stresses for 27 soil profiles from boreholes. Two input earthquake ground-motion levels corresponding to a 10% and 2% chance of exceedance in the next 50 years were examined. The results show the chance of liquefaction for the 10% motion is very low, but some soils may liquefy under the more extreme 2% motion. Published geological maps and over 3000 boreholes were used to develop liquefaction microzonation maps. A comparison was also made between the findings and liquefaction likelihood defined in China's Seismic Code.
Time-History Analysis on Seismic Stability of Nuclear Island Bedrock with wea...ijceronline
This paper presents a three-dimensional numerical simulation method for the seismic response calculation of nuclear island foundation based on the nuclear power plant in Tai Shan. There are two weak interlayers in the bedrock. The numerical simulation aimed at the analysis and the evaluation of the stability of bedrock with the consideration of the interaction between the bedrock and nuclear island. Main features of nuclear numerical model are: (1) the mechanical interaction of nuclear island buildings, turbine room and bedrock have been taken into consideration, (2) the two weak interlayers may decrease the stability of the bedrock, which are the focused research in the models, (3) non-reflective free field boundary have been used in the boundary condition of model. The commercial numerical software FLAC3D has also been used in the simulation and analysis. A finite difference of numerical model for nuclear island bedrock was established and it have been used to analyze the bedrock’s mechanical phenomenon and safety performance. Dynamic characteristics, distributions of mechanical parameters and failure characteristics of bedrock have been studied under the action of seismic wave.
Parametric analysis of ground temperature profile in bwari north central nigeriaAlexander Decker
This study analyzed ground temperature data collected over five years in Bwari, Nigeria to predict future climate changes and natural disasters. The results showed that net earth radiation has increased and rainfall has not been able to offset it. May typically had the highest average monthly ground temperatures. 2012 experienced major flooding in Nigeria. While 2013 may see increased solar radiation, reduced flooding is predicted; heavier flooding may occur in 2014 or 2015 due to the continued rise in net earth radiation not being balanced by natural forces.
This study estimates local site effects in the Ataköy area of Istanbul, Turkey through multiple techniques. A hybrid 3D finite-difference method is used to model site amplification from a scenario earthquake using a 3D velocity model of the local geology. Horizontal-to-vertical spectral ratios are calculated from microtremor recordings at 30 sites and compared to synthetic noise data from a 1D geological model. The results indicate the strongest amplifications around 1 Hz, with alluvial sites expected to experience amplification factors of 1.5-2. Comparing the different methods provides a comprehensive understanding of site effects in this densely populated and seismically hazardous area of Istanbul.
A Review of Change Detection Techniques of LandCover Using Remote Sensing Dataiosrjce
IOSR Journal of Computer Engineering (IOSR-JCE) is a double blind peer reviewed International Journal that provides rapid publication (within a month) of articles in all areas of computer engineering and its applications. The journal welcomes publications of high quality papers on theoretical developments and practical applications in computer technology. Original research papers, state-of-the-art reviews, and high quality technical notes are invited for publications.
This document summarizes a study that evaluated liquefaction potential in Babol City, Iran using both deterministic and probabilistic approaches. Over 600 soil borehole records from 60 sites were analyzed using 4 deterministic methods (including Seed) and 1 probabilistic reliability method. Microzonation maps identified liquefaction and non-liquefaction areas for each method. Results showed the reliability approach provided an accurate assessment of liquefaction potential. A 2D boundary line was also developed using (CSR) and (Nspt) parameters to identify liquefaction/non-liquefaction areas based on safety factors and probability. The study aims to assess liquefaction potential in Babol City and determine the most valid approach.
Naghizadehrokni et al-2018-geoenvironmental_disastersMehran Naghizadeh
This document summarizes a study that evaluated liquefaction potential in Babol City, Iran using both deterministic and probabilistic approaches. Over 600 soil borehole records from 60 sites across the city were analyzed using 4 deterministic methods (including Seed's method) and 1 probabilistic reliability method. Microzonation maps showed liquefaction and non-liquefaction areas from each method. The reliability approach was found to accurately assess liquefaction potential. A 2D boundary line was also developed from the data to identify liquefaction/non-liquefaction based on cyclic stress ratio and SPT resistance. The maps and boundary line produced can help identify liquefaction risk in Babol City.
Makalah ini membahas sejarah perkembangan web mulai dari penemuan teknologi web oleh Tim Berners-Lee di CERN hingga perkembangan browser dan standar-standar web."
Este documento presenta una introducción a la gerencia de proyectos de tecnología educativa. Explica que la gerencia de proyectos implica ejecutar actividades de manera temporal para crear un producto, servicio o resultado único, y requiere tomar decisiones, lograr objetivos y administrar recursos. También describe las características, el ciclo de vida, las fases y herramientas de un proyecto, así como los diferentes interesados que pueden afectarlo positiva o negativamente. El propósito es ofrecer una visión general de los
Dokumen tersebut membahas tentang perkembangan motorik pada anak usia 0-6 tahun. Ia menjelaskan tahapan-tahapan perkembangan motorik kasar dan halus pada setiap kelompok usia, mulai dari bayi hingga anak usia sekolah dasar. Tujuannya adalah agar dapat memahami perkembangan motorik yang sesuai pada setiap tahap usia anak.
Endo perio lesions /certified fixed orthodontic courses by Indian dental aca...Indian dental academy
The Indian Dental Academy is the Leader in continuing dental education , training dentists in all aspects of dentistry and offering a wide range of dental certified courses in different formats.
This document contains schedules for the Deontología Jurídica 40 course taught by JORJE LUIS GOMEZ on various dates in 2015 and 2016. It lists the time slots and instructor Lady García.
We represent the rights of people with personal injuries caused in auto accidents and other negligence. We help and represent people who wish to file bankruptcy or are suffering from creditor harassment.
The document describes a man's preparations for proposing to a girl. It details how he woke up early and practiced his proposal all day, including during meals and by practicing on other girls. That afternoon, he picked the girl up for a movie and romantic dinner, where he finally proposed to her after reciting the practiced lines. She said yes, and he put a ring on her finger.
This document proposes an exhibit at the Nantucket Historical Association highlighting the influence of women on Nantucket Island over time. It would feature case studies of important women and group them into four spheres showing their roles in Nantucket's social, cultural, economic and political development. The exhibit aims to provide a more well-rounded perspective on Nantucket history by incorporating women's histories, which have often been neglected. It discusses how the NHA is well-suited to host this exhibit through its resources and mission of sharing diverse stories from Nantucket's past.
ASSESSMENT OF LIQUEFACTION POTENTIAL OF SOIL USING MULTI-LINEAR REGRESSION MO...IAEME Publication
The Standard Penetration Test (SPT) is the most widely used in-situ test throughout the world for subsurface geotechnical investigation and this procedure have evolved over a period of 100 years. Estimation of the liquefaction potential of soils is often based on SPT test. Liquefaction is one of the critical problems in the field of Geotechnical engineering. It is the phenomena when there is loss of shear strength in saturated and cohesion-less soils because of increased pore water pressures and hence reduced effective stresses due to dynamic loading. In the present study, SPT based data were analysed to find out a suitable numerical procedure for establishing a Multi-Linear Regression Model using IBM-Statistical Package for the Social Sciences (IBM SPSS Statistics v20.0.0) and MATLAB(R2010a) in analysis of soil liquefaction for a particular location at a site in Lucknow City. A Multi-Storeyed Residential Building Project site was considered for this study to collect 12 borehole data sets along 10 km stretch of IIM road, Lucknow, Uttar Pradesh (India).
Improved analyses of liquefaction and settlementRobert Pyke
This is a further updated version of my presentation on the subject topic. It includes additional material on seismic settlements. The calculation of seismic settlements using simplified methods has been out of control for some time and is leading to expensive ground improvement when it is not necessary. An improved method of evaluation is described and illustrated by case histories.
Prediction of swelling pressure of expansive soils using compositional andIAEME Publication
The document discusses predicting swelling pressure of expansive soils using compositional and environmental factors. Expansive soils exhibit significant volume changes with moisture content variations, which can damage foundations. Directly determining swelling characteristics is expensive. The paper investigates how soil state (reflected by initial moisture content, dry density, and surcharge pressure) and soil type (reflected by liquid limit and plasticity index) influence predicted swelling pressure. 46 free swell oedometer tests were conducted on 4 soils, varying one factor at a time over practical ranges. Results show swelling pressure is associated with both compositional and environmental factors.
Pile response due to earthquake induced lateral spreadingeSAT Journals
Abstract To develop a home heating system with high efficiency, the outdoor temperature is not the only parameter to be considered but also disturbances such as ventilation, door/window openings and personal lifestyle. The aim of the project is to develop the home heating system which adapts itself to changing customer demands using fuzzy logic. The energy consumption and the outdoor temperature of the house were monitored over a period of one year to produce the data required to program the fuzzy controller and thereby the appropriate set temperature will be determined. When load disturbances such as door/window openings are given, there is an increase in the energy required by the heater. This additional energy is obtained as an output from the fuzzy Abstract Liquefaction assessment is a key aspect when the pile foundations are designed under seismic loading. The liquefaction associated with lateral spreading and flow failures that can affect the overall stability of the pile foundations. This study is emphasized to investigate the extent of the liquefaction zone and the effect of the liquefaction on the pile is also monitored by the means of estimating the maximum bending moment developed due to lateral ground displacement. The investigation site is located at I.I.T. Kharagpur Extension Centre, Block No. HC, Plot. 7, Sector-III, Salt Lake City, Kolkata, India. The diameter and pile shaft length are 0.45 m and 22 m, respectively. The soil samples are collected from three boreholes located at the site of investigation and it is explored to a depth up to 30.45 m below the ground level. The boreholes reveal that the subsoil generally consists of six types of soil layers and the water table is at a depth of 1.25 m below the ground surface. A finite element model is simulated as per the field conditions using QUAKE/W (GeoStudio, 2007) to determine the depth of the liquefaction zone. The soil layers are idealized as 14 nodded rectangular elements. Initial static and dynamic analyses is performed by considering the linear elastic and equivalent linear models of soil using the earthquake history of peak acceleration of 0.16g. It is observed that the layer 1 susceptible to liquefaction due to high excess pore water pressure in that layer. Analytical study is carried out for the estimation of the maximum bending moment induced in the pile subjected to lateral ground displacement. The maximum deflection of the pile is also estimated due to the lateral ground displacement caused by the liquefaction. Index Terms: Earthquake, Ground displacement, Lateral spreading, Liquefaction, Pile
This document summarizes a study that used finite element analysis to investigate the effect of liquefaction on pile foundations. The study site was in Kolkata, India and consisted of 6 soil layers overlying a groundwater table. Finite element models using QUAKE/W software modeled the site with linear elastic and equivalent linear soil models considering an earthquake with 0.16g peak acceleration. The analyses found the first soil layer was susceptible to liquefaction due to high excess pore pressures. Bending moment and displacement of a pile foundation due to lateral ground spreading were also estimated.
DETERMINATION OF STRENGTH OF SOIL ANDIT’S STABILITY USING ULTRASONIC PULSE VE...IRJET Journal
This document discusses using ultrasonic pulse velocity testing to determine the strength and stability of soil. Specifically, it examines using this non-destructive testing method on compacted soil samples with different stabilizer contents. The study analyzes how stabilizers like ground granulated blast furnace slag affect the engineering properties of clayey soil. It details the methodology of mixing soil with varying amounts of stabilizer, compacting the mixtures, and then conducting ultrasonic pulse velocity tests to measure the soil's density and modulus of elasticity. Graphs of density and velocity versus water content are used to evaluate the compaction characteristics and determine if ultrasonic testing can provide a fast alternative to standard compaction tests.
1. The document summarizes methods for assessing liquefaction and post-liquefaction settlement, including simplified and effective stress methods.
2. Simplified methods use empirical correlations between in-situ tests like SPT and CPT to determine liquefaction potential, while effective stress methods directly model pore pressure buildup using constitutive soil models.
3. Both methods have uncertainties from earthquake loading, soil properties, and testing, though effective stress modeling is more accurate but relies on precise soil parameters. The document proposes a probabilistic approach using logic trees to account for uncertainties.
Statistical evaluation of compression index equationsIAEME Publication
This document discusses statistical evaluation of equations for predicting the compression index (Cc) of soils. Twelve commonly used equations that predict Cc based on parameters like liquid limit, plasticity index, dry density, and void ratio are considered. Statistical analysis is performed to evaluate the effectiveness of the equations. One-way and two-way analysis of variance (ANOVA) tests are conducted using a database of 178 soil samples to compare predicted and observed Cc values. The tests indicate that soil classification and prediction method have a significant influence on the deviation between predicted and observed Cc. Certain models are found to be applicable only to some soil classification groups. The best models for different soil groups and for all soil types are identified using statistical tests.
The document provides background information on the COPE field campaign and the goals and instrumentation of the COPE-MED research project. The COPE campaign studied convective storms in southwest England through aircraft and ground-based radar observations. COPE-MED aims to investigate microphysical pathways and entrainment effects on precipitation formation. Key goals are to analyze cloud liquid water content and droplet number concentration measurements from the campaign and examine droplet spectral characteristics during non-precipitating cloud penetrations.
mine dump on seismic load and introduction of geogrid preview Joydeep Atta
1) The document discusses the use of numerical modeling to analyze the stability of overburden dump slopes in open cast mines under blast loading and seismic excitation, with and without the use of geogrid reinforcement.
2) Laboratory tests are proposed to determine material properties of the dump material and geogrid, which will be inputs for the numerical model in PLAXIS.
3) The numerical model will analyze the factor of safety of slopes under dynamic loading conditions and with geogrid to see how it increases stability and allows steeper slopes.
This document summarizes a study that used centrifuge modeling to analyze the seismic loading response of layered brick soil. Centrifuge modeling allows for scaled physical modeling of geotechnical problems involving gravity effects. The study involved constructing a layered brick soil model in a centrifuge and subjecting it to simulated earthquake motions while monitoring soil responses like settlement, pore pressure, and acceleration. The results provided data on how the layered soil responded dynamically to seismic loads at different frequencies and strain levels, helping to validate numerical models and further the understanding of soil failure mechanisms during earthquakes.
This document summarizes a study that used centrifuge modeling to analyze the seismic loading response of layered brick soil. Centrifuge modeling allows for scaled physical modeling of geotechnical problems involving gravity effects. The study constructed a layered brick soil model in a flexible shear box container and subjected it to various ground motions up to an acceleration of 58g using a shaking table. A variety of sensors measured soil responses like settlement, pore pressure, and acceleration at different depths during testing. The results provide data on how the layered soil responds nonlinearly to seismic loads and frequencies, with implications for seismic design of offshore structures.
The cutting-edge applications that the engineers are bringing with using finite element procedure for the human civilization and the emergence of new techniques in solving real-life scenarios in finite element procedures.
Analytical study on soil pile interaction effect in the variation of natural ...IAEME Publication
This document summarizes an analytical study on how the natural frequency of a single pile foundation varies with soil-pile interaction effects. It presents the theoretical formulation for calculating the depth of fixity and natural frequency of a pile based on the soil modulus and pile diameter. A finite difference method and MATLAB code were used to model the soil-pile system and conduct a parametric study. The results show that the natural frequency non-linearly decreases with lower soil modulus and smaller pile diameter. An equation was developed through regression analysis to predict the natural frequency based on the soil and pile properties. Understanding how natural frequency varies with soil-pile interaction is important for designing foundations subjected to dynamic loads.
This document summarizes a study estimating geo-mechanical properties of reservoir rocks from well log data. The study presents a method to predict shear wave velocity from compressional wave velocity, porosity, and shale content when direct shear wave measurements are unavailable. Elastic properties including Poisson's ratio, shear modulus, bulk modulus, and Young's modulus are then calculated. These properties allow evaluation of formation strength and prediction of safe production rates without sand production. The results show shear and compressional wave velocities are linearly related. Calculated combined modulus of strength and shear modulus to compressibility ratio values indicate the formations can generally be produced safely below an optimum flow rate without significant sand production risks.
Estimating geo mechanical strength of reservoir rocks from well logs for safe...Alexander Decker
This document summarizes a study that estimated geo-mechanical properties of reservoir rocks from well log data in order to determine safety limits for sand-free hydrocarbon production. The study used well logs to predict shear wave velocity and then calculate elastic moduli, which can indicate a formation's mechanical strength. The results showed that the combined modulus of strength and shear modulus to compressibility ratio for the formations were relatively low, suggesting sand production should not occur below certain flow rates. This information on a formation's mechanical properties can help minimize risks during hydrocarbon exploration and production.
14. Mechanism of Liquefaction Response in Sand–Silt Dynamic.pdfPinakRay2
This document summarizes a study analyzing the process of dynamically induced liquefaction in two centrifuge soil models tested as part of the VELACS project. The models consisted of saturated sand overlain by silt layers, representing prototypes of a level site and an embankment. Accelerations recorded during shaking were used to evaluate shear stress and strain histories at different depths, shedding light on mechanisms of lateral deformation, stiffness degradation, and possible densification during liquefaction. The identified response patterns from the centrifuge tests were found to be comparable to those from laboratory cyclic loading tests.
This study establishes a correlation between Standard Penetration Test N-values (SPT-N) and internal friction angles for soils in Sri Lanka. 25 soil samples were collected and tested in a laboratory to determine soil types, shear strength parameters, moisture content, density, etc. Correlations between SPT-N values and friction angles were developed using regression analysis in SPSS. The analysis found the highest correlation with the square root of SPT-N. The proposed correlation equation had high reliability and was within the range of existing correlations, indicating its accuracy for estimating friction angles using SPT-N values in the local context of Sri Lanka.
Effect of fines on liquefaction using shake table testeSAT Journals
calamities resulting into considerable damages. One of the most detrimental
effects caused due to earthquake is liquefaction. This paper deals with experimental investigation of effects of fines content on
liquefaction behavior using shake table test. A test program consisted of total 19 tests conducted on saturated cohesionless sand
with varying amount of non-plastic silt. The behavior of such silty sand in the relative density range 30 to 60% has been studied
by subjecting the specimens to a specific acceleration of 0.54g. Effect of silt content and the relative density on generation of pore
pressure and thereby initiation of liquefaction has been studied. The results obtained from the present study showed that cyclic
stress ratio (CSR) values decrease with the increase in fines content for lower relative densities. Delay in development of pore
pressure is observed with the increasing fines content. This indicates that higher silt contents at higher densities offer better
resistance to liquefaction. Further, for lower densities and lesser silt contents liquefaction occurred at pore pressure ratio even
less than one. The trend observed for CSR and relative density is similar when compared with triaxial test reported in literature.
The points where liquefaction has occurred in the field, when checked in the present study, they lie in ‘YES’ zone of liquefaction.
Keywords: Relative Density, Cyclic Stress Ratio, Pore Pressure Ratio, Liquefaction Resistance, Initiation of
Liquefaction
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2. Z. A. DERELI et al. / International Journal of Engineering Issues
18
Earthquake (1964) and Izmit earthquake (1999). There are laboratory and in situ tests and many other procedures to
evaluate the liquefaction potential. In situ tests are more common than laboratory tests due to the disturbing problem
of cohesionless soil. Standard penetration test (SPT), which is the mostly-used one, cone penetration test (CPT) and
shear wave velocity measurements are in-situ test methods to evaluate the liquefaction assessment. For each test,
there are analytical evaluation techniques. Simplified procedure depends on SPT. Liquefaction evaluating procedures
have been developed by scientists since the 1970s. There are many research studies and suggestions about stress
reduction coefficient. Additionally there are many other studies about magnitude correction factor, stress correction
factor and other correction factors to reach real situations.
Developing computer technologies provides good solutions especially for complex problems. Artificial
intelligence is one of these new technologies. It works like a nerve cell in the brain. For this reason, it is also named
neural networks. Neural network is used in variety of areas to solve medical, scientific and engineering problems. It
can be used in geotechnical engineering as well. The application of neural networks in geotechnical engineering
problem is a new area. Neural Network Algorithms give better result for evaluating liquefaction assessments.
The aim of the current study is to investigate the evaluation of liquefaction assessment with neural network
algorithm and indicate the effect of parameter for liquefaction occurrence.
A. Liquefaction Analysis with SPT
Liquefaction is defined as the transformation of a granular material from a solid to a liquefied state as a
consequence of increased pore water pressure and reduced effective stress (Marcuson, 1978). Liquefaction analysis
may be necessary if a facility has liquefaction potential. Especially, in heavily urbanized areas which also have high
seismic risk, the assessment of the liquefaction potential of surface soil needs an exhaustive geotechnical
investigation and calculation.
According to Seed and Idriss (1982); Marcuson, (1990); and Youd et al. (2001), fine soils can liquefy.
Nevertheless, initially liquefaction is relevant only to sand. It was well recognized for a long time that clean sands
with few fines are susceptible to liquefaction. However, in the past two to three decades and following the
observations during strong earthquakes in China, Turkey and Taiwan, it is concluded that non-plastic to low
plasticity fine grained materials - as well as granular material - may also be subjected to classical liquefaction.
Boulanger and Idriss (2004) review the mechanisms of liquefaction of no to low plasticity fine grain materials
subjected to cyclic loading. Taking into account recent advances on this subject, the latter reference uses the term
“liquefaction” to describe the onset of high excess pore water pressures and large shear strains during undrained
cyclic loading of sand-like soils, while term “cyclic failure” is used to describe the corresponding behavior of clay-
like soils.
Laboratory tests are not very well accepted for liquefaction analysis due to difficulties to obtain undisturbed
and representative samples from non-cohesive soils. In order to evaluate the liquefaction assessment, there are
commonly used four in-situ test methods which are standard penetration test (SPT), cone penetration test (CPT),
shear wave velocity measurements, and Becker penetration test (BPT). For each test, there are analytical evaluation
techniques.
SPT is relatively simple and very well developed. Seed et al. (2003) claim that the oldest and most widely-used
in-situ testing method for liquefaction assessment is the SPT method. Furthermore, SPT-based correlations for
liquefaction assessments have been in use for relatively long time and are validated by numerous case histories.
Various evaluation methods have been proposed for liquefaction assessment using SPT method such as Seed and
Idriss Simplified method (Seed et al. 1984), Youd and Idriss (2001), and Cetin et al. (2004). Most of the available
liquefaction analysis procedures follow the formats initially used in Seed and Idriss simplified method.
The assessment of liquefaction potential includes two main stages which are evaluating the effect of earthquake
loading on soil, and evaluating soil strength against earthquake loading. The earthquake loading on soil is expressed
using the term Cyclic Stress Ratio (CSR), and the soil strength (capacity of soil) to resist liquefaction is expressed
using Cyclic Resistance Ratio. The capacity of the soil to resist liquefaction was denoted using different symbols.
Seed and Harder (1990) used the symbol CSRl; Youd (1993) used the symbol CSRL; and Kramer (1996) used the
symbol CSRL to denote this. Yet, the NCEER workshop (Youd et al., 2001) recommends the use of CRR to denote
the soil resistance against liquefaction, and this notation is followed in this study.
3. Z. A. DERELI et al. / International Journal of Engineering Issues
19
Seed and Idriss (1971) formulated the equation for calculation of the cyclic stress ratio:
CSR = 0.65
σv
σv
′
amax
g
rd (1)
Where,
σv : Total vertical overburden stress
σv
′
: Effective vertical overburden stress
amax : Peak horizontal ground surface acceleration
g : The acceleration of gravity
rd : Stress reduction factor
1996 NCEER and 1998 NCEER/NSF Workshops (Youd et al., 2001) recommend “Figure 1” to evaluate
the cyclic resistance ratio (CRR). According to the figure, CRR depends on fine content and SPT corrected blow
count (N1)60.
Factor of safety for liquefaction can be calculated basically as:
FS =
CRR
CSR
(2)
Figure 1. SPT Clean-Sand Base Curve for Magnitude 7.5 Earthquakes with Data from Liquefaction Case Histories
(Modified from Seed et al. 1985)
B. Neural Network Algorithm
Neural network systems are a kind of Artificial Intelligence (AI). They are considerably the same. Saka and
Ural (1998) indicate that they are massively parallel systems that rely on dense arrangements of interconnections and
simple processors. The name of artificial neural network depends on its similarity to neurons in the brain. They are
motivated by the neuronal architecture and operation of the brain. Although in artificial neural network models the
4. Z. A. DERELI et al. / International Journal of Engineering Issues
20
majority of biological details are eliminated, they contain enough structure observed in the brain to provide insight
into how biological neural processing occurs. Neural network algorithms use a processing structure that has
numerous processing units and many interconnections between them. Each unit is connected to many of its
neighbors; therefore, there are huge numbers of connections. Thus, these connections provide power of neural
network (Ural, 1998)
Neural Network Systems are used in a great variety of application areas that include medical, scientific and
engineering problems. Ordinary equation and model can be replaced with neural networks to analyze problems.
Analyses that involve many variables become more convenient in neural network. The application of neural
networks in geotechnical engineering problem is a new area.
There are many neural networks algorithms. Back propagation and generalized regression neural network are
two of the common examples. According to Saka and Ural (1998), back propagation is the most widely-used of
neural network paradigms and has been applied successfully in applications in a broad range of areas. Back
propagation networks are usually layered. Each layer is linked to the layers below and above. Figure 2 demonstrates
an example of a typical back-propagation neural network (BPNN). The external inputs only receive from the input
layer that is the bottom layer in figure. The inputs for Figure 2 are earthquake magnitude (M), peak ground surface
acceleration (amax), relative density (DR), shear modulus (G), and total and effective stresses. (, ’). The top layer
is the output layer. The layer between the input and output is the hidden layer. Each unit in the hidden layer is linked
to all units in below and above layer. None of the units in this structure are connected to other units in the same
layer. Each interconnection has associated connection strength, given as wji, the weight to unit j from unit i. Weights
associated with each interconnection are adjusted during the training of the network. In back-propagation algorithm,
training is supervised, in which case the network is presented with target answers for each pattern that is input
(Ural,1998; Liquefaction Assessment by Artificial Neural Networks).
Figure-2. An example of a typical back-propagation neural network layers.
Learning algorithm of the back-propagation includes a forward-propagating step followed by a backward-
propagating step. Both of the steps are done for each pattern presentation during training. The forward-propagation
step begins with the presentation of the output value of each processing unit; propagate forward through the hidden
layers. All processing units, that is, each successive layer sums its inputs and implements a sigmoid function to
calculate its output. The units of output layer generate the output of the network. (Ural, 1998; Liquefaction
Assessment by Artificial Neural Networks)
The Generalized regression neural networks (GRNN) are similar to radial basis function networks. In a GRNN,
each neuron in the mapping layer represents a Gaussian bump that coincides exactly with one of the inputs from the
training set. Since there is exactly one neuron for each training example, the weights are simply set by hand, using
the input and output feature vectors for each example. The training time is therefore zeroed and the weights are
initialized to the coordinates of the feature vectors in the training set. Unfortunately, because the training examples
do not optimally cover the input space, many of the neurons are wasted, and thus more neurons are needed to
achieve the same error level as would occur in a radial basis function network, which makes them even slower than
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RBF networks at producing an output (Use of Artificial Neural Networks in Geomechanical and Pavement Systems,
Transportation Research, 1999).
Neural network analysis involves two main stages: training and testing. In the training stage, neural networks
learn the relationship between input and output from an educational group. Then, in the testing stage, in order to
measure the generalization ability of the network, it is tested against educational group. Education should be
repeated until logical output is produced by convenient inputs.
In order to develop neural network, selecting data is one of the most significant stages for training the neural
networks due to the fact that neural networks are powerful in interpolation compared to extrapolation. For this
reason, training data should cover all aspects of the problem. Moreover, neural network may not learn the data due to
specific sort of data. This leads network to lose its learning power.
Artificial Neural Networks were applied to evaluate the assessment of soil liquefaction potential. The goal of
networks is to forecast whether soil layers liquefy or not. Input parameters of neural network are obtained from the
standard penetration test. The occurrence of liquefaction is the output parameter. Ten input variables including depth
(z), ground water table (m), total vertical stress σv (kPa) effective vertical stress σv’ (kPa), fines content (%),
corrected SPN-N number, N1(60), maximum surface acceleration, magnitude (M), cyclic resistance ratio (CRR),
cyclic stress ratio (CSR) were used for ANN model development.
II. CASE STUDY
A report called “SPT-Based Liquefaction Triggering Procedures” by I. M. Idriss and Ross W. Boulanger was
published in December, 2010 which presents an updated examination of SPT-based liquefaction triggering
procedures for cohesionless soils, with the specific purpose of updating and documenting the case history database,
providing more detailed illustrations of the database distributions relative to liquefaction triggering correlation by
Idriss and Boulanger (2004, 2008), re-examining the database of cyclic test results for frozen sand samples,
presenting a probabilistic version of the Idriss-Boulanger (2004, 2008) liquefaction triggering correlation using the
updated case history database, presenting a number of new findings regarding components of the liquefaction
analysis framework used to interpret and extend the case history experiences, and presenting an examination of the
reasons for the differences between some current liquefaction triggering correlations.
This report describes the updated database of SPT-based liquefaction/no liquefaction case histories (Cetin et al.
(2004) liquefaction triggering database). The selection of earthquake magnitudes, peak accelerations, and
representative (N1)60cs values are described, and the classification of site performance is discussed as well.
The SPT-based case history database used to develop the Idriss and Boulanger (2004, 2008) liquefaction
correlation for cohesionless soils is updated in this report, with the following specific goals of incorporating
additional data from Japan; incorporating updated estimates of earthquake magnitudes, peak ground accelerations,
and other details where improved estimates are available; illustrating details of the selection and computation of SPT
(N1)60cs for a number of representative case histories; and presenting the distributions of the database relative to the
various major parameters used in the liquefaction triggering correlation. The updated database described in this
report incorporates the 44 Kobe proprietary cases which were provided by Professor Kohji Tokimatsu (2010,
personal communication), an additional 26 case histories summarized in Iai et al. (1989), and a small number of
other additions.
The total number of case histories in the updated database is 230, among which 115 cases had surface evidence
of liquefaction, 112 cases had no surface evidence of liquefaction, and 3 cases were at the margin between
liquefaction and no liquefaction.
Our database is created by filtering the extreme values of liquefaction possibilities and omitting 73 case
histories from the list. 56 case histories for non-liquefaction and 101 case histories for the evidence of liquefaction
are taken into consideration. Thus, the total number of case histories used in our models is 157. The case histories
database is given in the appendices.
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III. ANALYSIS
As mentioned before, the datasets are arranged for 157 liquefaction cases and given in to the program. 107 of
them are for the training and the testing phases, and the last 50 are for the forecasting studies. 45 of 107 data in the
testing and the training phases exhibit non-liquefaction, while 52 of them are simulating the liquefaction
occurrences. Figure 3 represents an example dataset for the developed BPNN model.
Figure-3. An Example Input of dataset for the developed BPNN model.
Following this process, the input parameters which are depth, Z (m.); the ground water table, GWT (m.); the
effective stress, σv, σv’ (kPa); fines content (%); corrected SPN-N number, N1(60); max. acceleration, amax;
magnitude, M; cyclic resistance ratio, CRR; cyclic stress ratio, CSR are defined (Figure 4). The only output, the
liquefaction occurrence factor of safety (FS), is also defined. Then, the minimum, maximum and the means are
computed for the parameters (Figure 5).
Figure-4. The input and output parameters for neural network models.
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Figure-5. Defining the input and output parameters and the min., max, mean values for BPNN model.
As it is seen in Figure 6, %40 of the dataset are used for training, %28 of the dataset are used for testing and
finally last 50 data (%38 of the dataset) are used for the production phases as a forecasting study of liquefaction
analysis.
Figure-6. Test set extraction for the training, testing and forecasting phases.
In the network architecture options, the suitable neural network models are tested (for BPNN 12 architecture,
GRNN, etc.) and the most suitable architectures, which are BPNN with 3 hidden slabs and the GRNN, are used for
the analysis. For both architectures, the neuron numbers, scale functions, learning rates and etc. are defined as given
in Figure 7 and Figure 8.
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Figure-7. BPNN with 3 hidden slab architecture and its functions.
Figure-8. GRNN architecture and its functions.
In the neural network designer option, the training and stop criteria’s for the two models are defined as they can
be seen in Figure 9 and 10. Not to have an over-learning process, the calibration interval boundaries are chosen
carefully.
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Figure-9. Training and stop criteria for BPNN model.
Figure-10. Training and stop criteria for GRNN model.
A. Analysis Results
As for the results, the learning epochs, last average error, and minimum average errors in both the training and
the testing phases are evaluated by the program and given in Figure 11. As it is seen in Figure 12, there is no over-
learning since the calibration level is normal and the values get closer to zero by the epochs elapsed in the graph.
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Figure-11. Learning process for the BPNN model results.
Figure-12. Error – Epochs elapsed graph of BPNN model for over learning check.
The relative contribution (strength) factors that represent which factor affects the occurrence of liquefaction
mostly are evaluated and given in Figure 13. Also, the effects of each parameter on liquefaction occurrence (Total is
1.0) are given in Table 1.
Table-1. Effects of each parameter for liquefaction occurrence analysis (Total is 1.0).
CRR 0.173
CSR 0.153
N1(60) 0.127
M 0.107
amax 0.094
Z 0.091
GWT 0.073
σv
0.067
σv' 0.067
FC 0.048
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Figure-13. Relative Contribution (strength) Factors of BPNN Model.
The success rate of developed BPNN model is 91.9%, which is a really acceptable result for artificial neural
network models. The correlation coefficient, r, is equal to 0.96 as it is given in Table 2.
Table 2. Success rate of BPNN model.
File name:
C:UsersMTDesktopNN Model
2NN Model 2.pat
Patterns processed: 157
Output: C1
R squared: 0.9187
r squared: 0.919
Mean squared error: 0.016
Mean absolute error: 0.094
Min. absolute error: 0
Max. absolute error: 0.428
Correlation coefficient r: 0.9587
Percent within 5%: 29.907
Percent within 5% to 10%: 27.103
Percent within 10% to 20%: 31.776
Percent within 20% to 30%: 9.346
Percent over 30%: 1.869
The network values – actual values graph are given in Figure 14, and the success rate of the model can be
evaluated by looking at Figure 15. Thirteen data out of the total data are higher than 0.2. Therefore, the success rate
can be evaluated from “(157-13) / 157”, which is 91.72% by hand.
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Figure-14: The network values – actual values graph of BPNN model.
Figure-15: The actual network– actual graph of BPNN model for evaluating success rate.
As the results of GRNN model demonstrate, smoothing test generation value, last mean error, and minimum
mean errors in testing phase values are evaluated by the program and given in Figure 16.
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Figure-16. Learning process for the GRNN model results.
As it is seen in Figure 17, there is no over-learning since the calibration level is normal and the values goes to
zero by the epochs elapsed in the graph.
Figure-17. Error – Epochs elapsed graph of GRNN model for over learning check.
The success rate of the developed GRNN model is 97.8%, which is a really good result and better than the
developed BPNN model. The correlation coefficient, r, is equal to 0.989 as it is given in Figure 18.
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Figure-18. Success rate of GRNN model.
The error numbers, the success rates, the standard deviation values and the total average difference for the
BPNN and GRNN models are compared and given in the Table 3.
Table-3. Comparison of BPNN and GRNN model results.
BPNN GRNN
Error % 18 0
Success % 82 100
Standard Deviation 0.23 0.07
Ave. Difference: 0.37
B. Comparison of Methodologies
The results for the 32 data which is forecasted by the developed BPNN and GRNN models and also the results
from the simplified methodologies of Youd and Tokimatsu are given in Table 4 with the average values and the
maximum difference of these four methodologies.
Table-4.
Youd et al. (2001)
Tokimatsu and
Yoshimi (1983)
BPNN GRNN Averages Differences
0.43 0.58 0.76 0.61 0.60 0.32
1.08 1.34 1.58 1.38 1.34 0.50
1.21 1.51 1.34 1.49 1.39 0.30
0.61 0.73 0.99 0.74 0.77 0.38
0.78 0.89 1.21 0.84 0.93 0.42
0.68 0.80 1.12 0.81 0.85 0.44
1.49 2.00 1.79 1.74 1.75 0.51
1.06 1.33 1.57 1.33 1.32 0.51
0.61 0.71 0.98 0.72 0.75 0.37
0.56 0.67 0.92 0.67 0.70 0.36
0.81 1.42 1.51 1.46 1.30 0.70
0.68 0.83 1.16 0.80 0.87 0.49
0.75 0.91 1.27 0.88 0.95 0.52
0.76 0.83 1.15 0.81 0.89 0.39
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31
0.45 0.62 0.76 0.63 0.61 0.32
0.51 0.63 0.80 0.65 0.65 0.29
0.84 1.00 1.38 1.03 1.06 0.54
0.68 0.91 1.03 0.95 0.90 0.35
0.78 0.79 0.98 0.79 0.83 0.20
0.76 0.82 0.96 0.83 0.84 0.20
0.48 0.50 0.53 0.51 0.50 0.05
0.38 0.46 0.50 0.51 0.46 0.13
0.38 0.46 0.46 0.52 0.46 0.14
0.49 0.58 0.77 0.70 0.64 0.27
0.24 0.38 0.43 0.48 0.38 0.23
0.46 0.59 0.75 0.62 0.60 0.29
0.35 0.43 0.45 0.46 0.42 0.11
0.78 1.95 1.73 1.72 1.55 1.17
0.18 0.25 0.20 0.30 0.23 0.12
0.35 0.42 0.44 0.51 0.43 0.16
0.78 1.25 1.43 1.18 1.16 0.65
0.53 0.66 0.91 0.69 0.70 0.39
0.61 1.05 1.24 1.18 1.02 0.63
0.42 0.52 0.54 0.56 0.51 0.15
0.64 1.12 1.30 1.18 1.06 0.66
0.70 0.88 1.18 0.79 0.89 0.48
0.58 0.65 0.92 0.74 0.72 0.35
0.47 0.54 0.66 0.51 0.55 0.20
0.43 0.55 0.71 0.51 0.55 0.28
0.47 0.53 0.69 0.56 0.56 0.23
0.32 0.38 0.38 0.45 0.39 0.13
0.70 0.82 1.13 0.79 0.86 0.43
0.26 0.34 0.32 0.30 0.30 0.09
1.02 1.81 1.71 1.78 1.58 0.79
0.37 0.50 0.64 0.55 0.52 0.27
0.37 0.51 0.59 0.52 0.50 0.22
0.83 1.45 1.58 1.56 1.36 0.75
0.49 0.63 0.86 0.61 0.65 0.37
0.58 0.74 1.05 0.69 0.77 0.48
0.67 0.75 0.99 0.78 0.80 0.32
Ave. Difference: 0.37
IV. CONCLUSION
An overview of the different methods of evaluating soil liquefaction occurrence problem during earthquakes is
presented in this paper. Based on the Youd et al. (2001) equation and Tokimatsu and Yoshimi (1983) equations, the
evaluation is done by using simplified methods. The results are meaningful; they are approximately in the same
ranges.
As a result of the need for using more reliable and fast analysis in civil engineering, artificial neural network
algorithm is used nowadays especially in geotechnical engineering problems. However, the results are discussed by
researchers and is connected to the result that NN analyses are suitable in this area.
16. Z. A. DERELI et al. / International Journal of Engineering Issues
32
Due to this situation, a comparison of different kinds of methodologies for liquefaction analysis is done in this
study. Different kinds of NN algorithms, which are GRNN, BPNN, Kohonen, Probabilistic and GMDH are tested,
and two of them are discussed in this paper due to the better success rates.
In conclusion, it is shown that GRNN is better than BPNN algorithm for these problems. Furthermore, GRNN
gives approximately the same results with Tokimatsu and Yoshimi (1983) simplified method. Moreover, it can be
said that using neural network algorithms for liquefaction analysis saves our time by giving accurate and reliable
results in an easiest way.
For future studies, collecting more datasets from different cases and increasing the distribution of soil and
earthquake property types may help us conduct more successful liquefaction analysis. Thus, we recommended a
web-based soil dataset portal in a suitable format for researchers who use neural network algorithms.
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