Rock brittleness is one of the most important issues in rock mechanics. There is not yet an available method for defining or measuring directly the rock brittleness. The aim of this study is to suggest a new chemical index parameter for the prediction of basaltic rocks’ brittleness. In the order of that abovementioned purpose, a total of 23 basaltic rock samples were collected from different region of Turkey. Samples were initially tested to determine their chemical properties. Then, mechanical tests were carried out to define the brittleness indices (B1, B2, and B3) for each corresponding sample. Finally, relations between parameters obtained from test results and brittleness indices were examined with regression analysis. According to the results obtained, a new chemical parameter (CP) was proposed for predicting brittleness via major oxide element components of basaltic rocks. It was found out that, B1 and B2 are not reliable parameters for predicting the different properties, however; B3 and CP can be employed as good criteria for predicting the different properties of basaltic rocks (especially in terms of chemical and mechanical properties). ARTICLE INFO
{"title":"A new approach for the prediction of brittleness index based on chemical properties of basaltic rocks","authors":"C. Bilen","doi":"10.13168/AGG.2021.0020","DOIUrl":"https://doi.org/10.13168/AGG.2021.0020","url":null,"abstract":"Rock brittleness is one of the most important issues in rock mechanics. There is not yet an available method for defining or measuring directly the rock brittleness. The aim of this study is to suggest a new chemical index parameter for the prediction of basaltic rocks’ brittleness. In the order of that abovementioned purpose, a total of 23 basaltic rock samples were collected from different region of Turkey. Samples were initially tested to determine their chemical properties. Then, mechanical tests were carried out to define the brittleness indices (B1, B2, and B3) for each corresponding sample. Finally, relations between parameters obtained from test results and brittleness indices were examined with regression analysis. According to the results obtained, a new chemical parameter (CP) was proposed for predicting brittleness via major oxide element components of basaltic rocks. It was found out that, B1 and B2 are not reliable parameters for predicting the different properties, however; B3 and CP can be employed as good criteria for predicting the different properties of basaltic rocks (especially in terms of chemical and mechanical properties). ARTICLE INFO","PeriodicalId":50899,"journal":{"name":"Acta Geodynamica et Geomaterialia","volume":"1 1","pages":"285-299"},"PeriodicalIF":0.9,"publicationDate":"2021-05-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48856393","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In this work, we successfully identified seismic events (observations of earthquakes) in seismograms using a Convolutional Neural Network (CNN). In accordance with past (analogue) seismogram interpretations, we did not treat digital seismograms as a time series, as per the general method, but, rather, converted them into time snaps of continuous data flow. Multichannel seismograms were represented with a time-frequency domain in the form of multilayer images, with each signal channel forming one image layer. Images were then exposed to CNN (composed of three convolutional blocks whose architecture design was justified using Bayesian optimization). To improve reliability, we evaluated the posterior type function (PTP) as a combination of the probabilities of all of the considered classes of signal types (five in our case) which increased robustness of the identification. For data, we used records of acoustic emission (AE) events. The events were generated during laboratory loading experiments originally performed to study material/rock properties. As known, AE events may be studied in the same manner as natural earthquakes and treated in other ways as laboratory earthquake models. AE events are less complex compared to natural earthquakes where many of the physical parameters are known or may be controlled. Based on our results, we concluded that the successful identification of AE events is a necessary step prior to applying the proposed methodology for identifying natural earthquakes in seismograms.
{"title":"Type analysis of laboratory seismic events by convolutional neural network","authors":"P. Kolář","doi":"10.13168/AGG.2021.0019","DOIUrl":"https://doi.org/10.13168/AGG.2021.0019","url":null,"abstract":"In this work, we successfully identified seismic events (observations of earthquakes) in seismograms using a Convolutional Neural Network (CNN). In accordance with past (analogue) seismogram interpretations, we did not treat digital seismograms as a time series, as per the general method, but, rather, converted them into time snaps of continuous data flow. Multichannel seismograms were represented with a time-frequency domain in the form of multilayer images, with each signal channel forming one image layer. Images were then exposed to CNN (composed of three convolutional blocks whose architecture design was justified using Bayesian optimization). To improve reliability, we evaluated the posterior type function (PTP) as a combination of the probabilities of all of the considered classes of signal types (five in our case) which increased robustness of the identification. For data, we used records of acoustic emission (AE) events. The events were generated during laboratory loading experiments originally performed to study material/rock properties. As known, AE events may be studied in the same manner as natural earthquakes and treated in other ways as laboratory earthquake models. AE events are less complex compared to natural earthquakes where many of the physical parameters are known or may be controlled. Based on our results, we concluded that the successful identification of AE events is a necessary step prior to applying the proposed methodology for identifying natural earthquakes in seismograms.","PeriodicalId":50899,"journal":{"name":"Acta Geodynamica et Geomaterialia","volume":" ","pages":""},"PeriodicalIF":0.9,"publicationDate":"2021-05-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46963455","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Macro-mechnical charakteristics and their control on the strenght of sandstones of western Indo-Burmese Rangers, NE India","authors":"Raghupratim Rakshit","doi":"10.13168/AGG.2021.0017","DOIUrl":"https://doi.org/10.13168/AGG.2021.0017","url":null,"abstract":"","PeriodicalId":50899,"journal":{"name":"Acta Geodynamica et Geomaterialia","volume":"1 1","pages":"241-252"},"PeriodicalIF":0.9,"publicationDate":"2021-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46539904","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
We present the crustal deformation field in the Penola Strait – Lemaire Channel fault area (West Antarctica), based on the analysis of the 5 seasonal cycles of static GNSS survey. This 5 GNSS campaigns were conducted with approximately a 16-year interval from 2003 to 2019. The analyses indicate that average linear velocities of horizontal movements are multidirectional but no larger than 1 – 2 mm/yr. Average linear velocities of vertical movements are no larger than ±3 mm/yr. In the present work scheme of vertical and horizontal movements has been drawn out. The obtained results correlate well with the movements of the surrounding GNSS stations. Based on the analysis of spatial distribution of the Earth’s surface dilatation velocity the zones of extreme compression and expansion values were revealed. The analyses of spatial distribution of the Earth’s surface total shear velocity indicate that the studied region is horizontally heterogeneous. Based on the analysis of obtained results, a new kinematic model of fault area was developed. The possibility of using static GNSS survey to study recent local geodynamic processes in Antarctica has been demonstrated.
{"title":"Recent local geodynamic processes in the Penola Strait_Lemaire Channel fault area (West Antarctica)","authors":"I. Savchyn","doi":"10.13168/AGG.2021.0018","DOIUrl":"https://doi.org/10.13168/AGG.2021.0018","url":null,"abstract":"We present the crustal deformation field in the Penola Strait – Lemaire Channel fault area (West Antarctica), based on the analysis of the 5 seasonal cycles of static GNSS survey. This 5 GNSS campaigns were conducted with approximately a 16-year interval from 2003 to 2019. The analyses indicate that average linear velocities of horizontal movements are multidirectional but no larger than 1 – 2 mm/yr. Average linear velocities of vertical movements are no larger than ±3 mm/yr. In the present work scheme of vertical and horizontal movements has been drawn out. The obtained results correlate well with the movements of the surrounding GNSS stations. Based on the analysis of spatial distribution of the Earth’s surface dilatation velocity the zones of extreme compression and expansion values were revealed. The analyses of spatial distribution of the Earth’s surface total shear velocity indicate that the studied region is horizontally heterogeneous. Based on the analysis of obtained results, a new kinematic model of fault area was developed. The possibility of using static GNSS survey to study recent local geodynamic processes in Antarctica has been demonstrated.","PeriodicalId":50899,"journal":{"name":"Acta Geodynamica et Geomaterialia","volume":" ","pages":""},"PeriodicalIF":0.9,"publicationDate":"2021-04-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47863579","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The soil engineer needs to be able to readily identify difficult or problematic soils and to determine the amount of settlement that may occur. This paper deals with the assessment and identification of three types of difficult soils: collapsible soils, swelling soils, and liquefiable soils. In the first instance, the study investigates the effect of some soil properties on wetting-induced collapse strain and the swelling potential of soils. Also, two new methods for predicting soil collapse and swelling potential are developed. The proposed relationships correlate between collapse strain and swelling potential and some soil parameters which are believed to govern soil collapse and swelling. Validation of these two relationships with some data reported in literature is also examined. Furthermore, the paper describes the different steps suggested in a new procedure for soil liquefaction assessment. The procedure was presented in the form of an evaluation guide. In addition, a relationship was suggested for computing the potential for liquefaction. An application of the proposed procedure to a practical case is included in order to validate and illustrate the different steps to be followed in the suggested evaluation procedure. ARTICLE INFO
{"title":"Assessment and identification of three types of difficult soils","authors":"T. Ayadat","doi":"10.13168/AGG.2021.0015","DOIUrl":"https://doi.org/10.13168/AGG.2021.0015","url":null,"abstract":"The soil engineer needs to be able to readily identify difficult or problematic soils and to determine the amount of settlement that may occur. This paper deals with the assessment and identification of three types of difficult soils: collapsible soils, swelling soils, and liquefiable soils. In the first instance, the study investigates the effect of some soil properties on wetting-induced collapse strain and the swelling potential of soils. Also, two new methods for predicting soil collapse and swelling potential are developed. The proposed relationships correlate between collapse strain and swelling potential and some soil parameters which are believed to govern soil collapse and swelling. Validation of these two relationships with some data reported in literature is also examined. Furthermore, the paper describes the different steps suggested in a new procedure for soil liquefaction assessment. The procedure was presented in the form of an evaluation guide. In addition, a relationship was suggested for computing the potential for liquefaction. An application of the proposed procedure to a practical case is included in order to validate and illustrate the different steps to be followed in the suggested evaluation procedure. ARTICLE INFO","PeriodicalId":50899,"journal":{"name":"Acta Geodynamica et Geomaterialia","volume":" ","pages":""},"PeriodicalIF":0.9,"publicationDate":"2021-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48037585","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Distribution of metallogenic zones of the Caucasus region originated as a result of the subduction of the lithosphere of the Tethys Paleo-Oceanic plate under the East-European Paleo-Continental plate","authors":"A. Kharitonov","doi":"10.13168/AGG.2021.0014","DOIUrl":"https://doi.org/10.13168/AGG.2021.0014","url":null,"abstract":"","PeriodicalId":50899,"journal":{"name":"Acta Geodynamica et Geomaterialia","volume":"1 1","pages":"199-208"},"PeriodicalIF":0.9,"publicationDate":"2021-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45858872","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Procedures of using ground penetrating radar (GPR) and Sentinel-1 satellite synthetic aperture radar (SAR) were tested in the area of housing estates in Hodonín, where there is an intensive decrease in the subsoil and thus a significant cracking of prefabricated houses. Extensive geophysical research of the site provided essential information about active faults in the area. To prove them and define the most active deformation zones (blocks), where the maximum settlement of the subsoil occurs, the processed interferometric (InSAR) data from the Sentinel-1 SAR satellite were used. Results from joint evaluation of geophysical data and InSAR not only confirmed detected deformations but also notified on other locations with tendencies to subsidence in the neighborhood of main faults. The combination of the methods to identify displacement tendencies in urbanized areas is very effective. ARTICLE INFO
{"title":"Identification of ground instability in the housing estate complex based on georadar and satellite radar interferometry","authors":"F. Hubatka","doi":"10.13168/AGG.2021.0016","DOIUrl":"https://doi.org/10.13168/AGG.2021.0016","url":null,"abstract":"Procedures of using ground penetrating radar (GPR) and Sentinel-1 satellite synthetic aperture radar (SAR) were tested in the area of housing estates in Hodonín, where there is an intensive decrease in the subsoil and thus a significant cracking of prefabricated houses. Extensive geophysical research of the site provided essential information about active faults in the area. To prove them and define the most active deformation zones (blocks), where the maximum settlement of the subsoil occurs, the processed interferometric (InSAR) data from the Sentinel-1 SAR satellite were used. Results from joint evaluation of geophysical data and InSAR not only confirmed detected deformations but also notified on other locations with tendencies to subsidence in the neighborhood of main faults. The combination of the methods to identify displacement tendencies in urbanized areas is very effective. ARTICLE INFO","PeriodicalId":50899,"journal":{"name":"Acta Geodynamica et Geomaterialia","volume":" ","pages":""},"PeriodicalIF":0.9,"publicationDate":"2021-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45762898","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Owing to the disastrous consequences of ground subsidence in the urban area, great attention had always been accorded to areas with suspected signs of subsidence occurrence in order to mitigate its effect. Microgravity and electrical resistivity imaging (ERI) survey techniques were conducted at a parking lot of which possible occurrence of subsidence is anticipated due to the increased exposure of surface cracks and very slight depression. This study aimed to map and delineate the subsurface condition of the area with the view of revealing probable subsidence prone zones within the study area. To this end, the microgravity survey data was acquired at a station interval of 2 m. Pole-dipole configuration with 2 m electrode separation was adopted for the electrical resistivity imaging survey. The two methods showed good correlation with each other and proved their effectiveness in imaging the subsurface. A large proportion of the subsurface area was found to be residual soil (mainly silt and or clayey sand) with saturated zones identified by low gravity (< - 40.94 mGal) and resistivity (<150 Ω.m) values, which have the tendency to undergo expansion and contraction processes due to rise and fall in moisture content. The subsurface condition was found to be relatively stable, devoid of any subsidence triggering features such as voids or cavities. However, it is inferred to be unsuitable for engineering structures due to the expansive and contractive properties of the subsurface geomaterials (residual soil). Therefore, it is concluded that the area is not prone to subsidence and the surface cracks presents are mere effects of the expansion and contraction process, which could be avoided by the excavation of the expansive soil or good engineering design before the establishment of any structure.
{"title":"Application of microgravity and electrical resistivity imaging techniques to identify ground subsidence prone zone","authors":"M. Mohammed","doi":"10.13168/AGG.2021.0011","DOIUrl":"https://doi.org/10.13168/AGG.2021.0011","url":null,"abstract":"Owing to the disastrous consequences of ground subsidence in the urban area, great attention had always been accorded to areas with suspected signs of subsidence occurrence in order to mitigate its effect. Microgravity and electrical resistivity imaging (ERI) survey techniques were conducted at a parking lot of which possible occurrence of subsidence is anticipated due to the increased exposure of surface cracks and very slight depression. This study aimed to map and delineate the subsurface condition of the area with the view of revealing probable subsidence prone zones within the study area. To this end, the microgravity survey data was acquired at a station interval of 2 m. Pole-dipole configuration with 2 m electrode separation was adopted for the electrical resistivity imaging survey. The two methods showed good correlation with each other and proved their effectiveness in imaging the subsurface. A large proportion of the subsurface area was found to be residual soil (mainly silt and or clayey sand) with saturated zones identified by low gravity (< - 40.94 mGal) and resistivity (<150 Ω.m) values, which have the tendency to undergo expansion and contraction processes due to rise and fall in moisture content. The subsurface condition was found to be relatively stable, devoid of any subsidence triggering features such as voids or cavities. However, it is inferred to be unsuitable for engineering structures due to the expansive and contractive properties of the subsurface geomaterials (residual soil). Therefore, it is concluded that the area is not prone to subsidence and the surface cracks presents are mere effects of the expansion and contraction process, which could be avoided by the excavation of the expansive soil or good engineering design before the establishment of any structure.","PeriodicalId":50899,"journal":{"name":"Acta Geodynamica et Geomaterialia","volume":" ","pages":""},"PeriodicalIF":0.9,"publicationDate":"2021-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43977843","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The primary objective of this study is to analyze and characterize landslides in North Pakistan along Karakoram Highway (KKH) to produce a landslide susceptibility map using GIS and remote sensing technology. Using satellite images followed by field investigations, spatial distribution of landslide database was generated. Next, an integrated study was undertaken in the study area to perform the landslide susceptibility mapping. Dubaur-Dudishal section of KKH (about 150 km) which is a part of Kohistan Island Arc, is investigated in this study with a buffer zone of about 8 km along both sides of the KKH. Several thematic maps, e.g., lithology, distance to faults, distance to streams, distance to roads, normalized difference vegetation index (NDVI), slope, aspect, elevation, relative relief, plan-curvature and profile-curvature were prepared. Subsequently, these thematic data layers were analyzed by frequency ratio (FR) model and weights-of-evidence (WoE) model to generate the landslide susceptibility maps. In order to check the accuracy of the models, the area under the curve (AUC) was to quantitatively compare the two models used in this study. The predictive ability of AUC values indicate that the success rates of FR model and WoE model are 0.807 and 0.866, whereas the prediction rates are 0.785 and 0.846, respectively. Both methods show that nearly 50 % landslides in the study area fall in either high or very high susceptibility zones. The landslide susceptibility maps presented in this study are of great importance to the policy makers and the engineers for highway construction as well as the mega dams construction projects (Dasu dam and Bhasha dam which lie within the vicinity of the study area); so that proper prevention as well as mitigation could be done in advance to avoid the possible economic as well as the human loss in future. ARTICLE INFO
本研究的主要目的是分析和表征巴基斯坦北部喀喇昆仑公路(KKH)沿线的滑坡，利用GIS和遥感技术制作滑坡易感性图。利用卫星影像，结合野外调查，生成滑坡数据库的空间分布。其次，在研究区进行了综合研究，进行了滑坡易感性制图。KKH的Dubaur-Dudishal段(约150公里)是Kohistan岛弧的一部分，本研究对KKH两侧约8公里的缓冲区进行了调查。制作了岩性、断层距离、河流距离、道路距离、归一化植被指数(NDVI)、坡度、坡向、高程、相对起伏、平面曲率和剖面曲率等专题图。随后，利用频率比(FR)模型和证据权重(WoE)模型对这些专题数据层进行分析，生成滑坡敏感性图。为了检验模型的准确性，采用曲线下面积(area under the curve, AUC)对本研究中使用的两种模型进行定量比较。AUC值的预测能力表明，FR模型和WoE模型的预测成功率分别为0.807和0.866，而预测成功率分别为0.785和0.846。两种方法均表明，研究区近50%的滑坡落在高易感性区或极高易感性区。研究所得的滑坡敏感性图对公路建设和大型水坝建设项目(研究区附近的大苏坝和巴沙坝)的决策者和工程师具有重要意义;因此，适当的预防和缓解可以提前做，以避免未来可能的经济和人员损失。条信息
{"title":"Landslide susceptibility assessment along the Dubair-Dudishal section of the Karakoram Highway, Northwestern Himalayas, Pakistan","authors":"J. Iqbal","doi":"10.13168/AGG.2021.0010","DOIUrl":"https://doi.org/10.13168/AGG.2021.0010","url":null,"abstract":"The primary objective of this study is to analyze and characterize landslides in North Pakistan along Karakoram Highway (KKH) to produce a landslide susceptibility map using GIS and remote sensing technology. Using satellite images followed by field investigations, spatial distribution of landslide database was generated. Next, an integrated study was undertaken in the study area to perform the landslide susceptibility mapping. Dubaur-Dudishal section of KKH (about 150 km) which is a part of Kohistan Island Arc, is investigated in this study with a buffer zone of about 8 km along both sides of the KKH. Several thematic maps, e.g., lithology, distance to faults, distance to streams, distance to roads, normalized difference vegetation index (NDVI), slope, aspect, elevation, relative relief, plan-curvature and profile-curvature were prepared. Subsequently, these thematic data layers were analyzed by frequency ratio (FR) model and weights-of-evidence (WoE) model to generate the landslide susceptibility maps. In order to check the accuracy of the models, the area under the curve (AUC) was to quantitatively compare the two models used in this study. The predictive ability of AUC values indicate that the success rates of FR model and WoE model are 0.807 and 0.866, whereas the prediction rates are 0.785 and 0.846, respectively. Both methods show that nearly 50 % landslides in the study area fall in either high or very high susceptibility zones. The landslide susceptibility maps presented in this study are of great importance to the policy makers and the engineers for highway construction as well as the mega dams construction projects (Dasu dam and Bhasha dam which lie within the vicinity of the study area); so that proper prevention as well as mitigation could be done in advance to avoid the possible economic as well as the human loss in future. ARTICLE INFO","PeriodicalId":50899,"journal":{"name":"Acta Geodynamica et Geomaterialia","volume":" ","pages":""},"PeriodicalIF":0.9,"publicationDate":"2021-04-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48622054","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Stress controlled cyclic triaxial tests have been done on coastal sand of Digha, West Bengal, India, at different frequencies, confining pressures, and relative densities and cyclic stress ratios. Number of cycles for initial liquefaction (NL) has been determined for that number of cycle when excess pore pressure ratio has become equal to 1. Significant influences of density of sand, confining pressure and number of cycles for initial liquefaction on coastal Digha sand have been found. The test results have shown that increasing density of sand increases liquefaction potential, whereas cyclic strength of sand decreases with increase of confining pressure. An empirical correlation has been developed on cyclic strength of sand based on these parameters and this correlation fits quite well with the observed experimental results. Bender Element tests have been performed to determine maximum shear modulus (Gmax) of Digha sand at different densities and confining pressures. A high correlation coefficient between cyclic strength and Gmax of Digha sand at any NL has been found. A new pore water pressure generation model has been introduced for this sand along with upper bound and lower bound curves to predict excess pore water pressure build up due to seismic loads. ARTICLE INFO
{"title":"Liquefaction potential along with pore water pressure generation of coastal sand of Digha in West Bengal, India","authors":"Pinak Ray","doi":"10.13168/AGG.2021.0012","DOIUrl":"https://doi.org/10.13168/AGG.2021.0012","url":null,"abstract":"Stress controlled cyclic triaxial tests have been done on coastal sand of Digha, West Bengal, India, at different frequencies, confining pressures, and relative densities and cyclic stress ratios. Number of cycles for initial liquefaction (NL) has been determined for that number of cycle when excess pore pressure ratio has become equal to 1. Significant influences of density of sand, confining pressure and number of cycles for initial liquefaction on coastal Digha sand have been found. The test results have shown that increasing density of sand increases liquefaction potential, whereas cyclic strength of sand decreases with increase of confining pressure. An empirical correlation has been developed on cyclic strength of sand based on these parameters and this correlation fits quite well with the observed experimental results. Bender Element tests have been performed to determine maximum shear modulus (Gmax) of Digha sand at different densities and confining pressures. A high correlation coefficient between cyclic strength and Gmax of Digha sand at any NL has been found. A new pore water pressure generation model has been introduced for this sand along with upper bound and lower bound curves to predict excess pore water pressure build up due to seismic loads. ARTICLE INFO","PeriodicalId":50899,"journal":{"name":"Acta Geodynamica et Geomaterialia","volume":" ","pages":""},"PeriodicalIF":0.9,"publicationDate":"2021-04-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43491001","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：