S. Vinayagamoorthy, C. Anderson, B. Solan, B. Rankin, P. Mackinnon
The British standard constant-head triaxial test for measuring the permeability of fine-grained soils takes a relatively long time. A quicker test could provide savings to the construction industry, particularly for checking the quality of landfill clay liners. An accelerated permeability test has been developed, but the method often underestimates the permeability values compared owing to structural changes in the soil sample. This paper reports on an investigation into the accelerated test to discover if the changes can be limited by using a revised procedure. The accelerated test is assessed and compared with the standard test and a ramp-accelerated permeability test. Four different fine-grained materials are compacted at various water contents to produced analogous samples for testing using the three different methods. Fabric analysis is carried out on specimens derived from post-test samples using mercury intrusion porosimetry and scanning electron microscopy to assess the effects of testing on soil ...
{"title":"Influence of testing on permeability of compacted fine soils","authors":"S. Vinayagamoorthy, C. Anderson, B. Solan, B. Rankin, P. Mackinnon","doi":"10.1680/JGEEN.14.00147","DOIUrl":"https://doi.org/10.1680/JGEEN.14.00147","url":null,"abstract":"The British standard constant-head triaxial test for measuring the permeability of fine-grained soils takes a relatively long time. A quicker test could provide savings to the construction industry, particularly for checking the quality of landfill clay liners. An accelerated permeability test has been developed, but the method often underestimates the permeability values compared owing to structural changes in the soil sample. This paper reports on an investigation into the accelerated test to discover if the changes can be limited by using a revised procedure. The accelerated test is assessed and compared with the standard test and a ramp-accelerated permeability test. Four different fine-grained materials are compacted at various water contents to produced analogous samples for testing using the three different methods. Fabric analysis is carried out on specimens derived from post-test samples using mercury intrusion porosimetry and scanning electron microscopy to assess the effects of testing on soil ...","PeriodicalId":45150,"journal":{"name":"Geotechnical Engineering","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2015-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1680/JGEEN.14.00147","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67479486","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-06-05DOI: 10.1680/GENG.2002.155.4.263
A. Bond
The following are a selection of papers published recently in Geotechnique that readers of Geotechnical Engineering may find of particular interest. The selection concentrates on applied rather than pure research topics and covers issues published from April to September 2002.
{"title":"Recently in Géotechnique","authors":"A. Bond","doi":"10.1680/GENG.2002.155.4.263","DOIUrl":"https://doi.org/10.1680/GENG.2002.155.4.263","url":null,"abstract":"The following are a selection of papers published recently in Geotechnique that readers of Geotechnical Engineering may find of particular interest. The selection concentrates on applied rather than pure research topics and covers issues published from April to September 2002.","PeriodicalId":45150,"journal":{"name":"Geotechnical Engineering","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2015-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1680/GENG.2002.155.4.263","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67401575","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2009-02-01DOI: 10.1680/GENG.2009.162.1.33
A. Arulrajah, M. W. Bo, J. Chu, H. Nikraz
Ground improvement is often required in land reclamation projects on soft soil deposits to reduce future settlement under the projected future dead and live loads. In the case of thick deposits of marine clay, it is often necessary to accelerate the consolidation process of the clay using prefabricated vertical drains. In such projects, the degree of improvement has to be ascertained to confirm whether the soil has achieved the required degree of consolidation before the removal of surcharge. This analysis can be carried out by means of observational methods for which the ground behaviour is continuously monitored from the date of instrument installation. This paper provides a case study of the applications of geotechnical instrumentation for construction control in the Changi East reclamation project in the Republic of Singapore. Field instruments adopted in this project included settlement plates, deep settlement gauges, earth pressure cells, pneumatic piezometers, electric piezometers and water standpi...
{"title":"Instrumentation at Changi land reclamation project, Singapore","authors":"A. Arulrajah, M. W. Bo, J. Chu, H. Nikraz","doi":"10.1680/GENG.2009.162.1.33","DOIUrl":"https://doi.org/10.1680/GENG.2009.162.1.33","url":null,"abstract":"Ground improvement is often required in land reclamation projects on soft soil deposits to reduce future settlement under the projected future dead and live loads. In the case of thick deposits of marine clay, it is often necessary to accelerate the consolidation process of the clay using prefabricated vertical drains. In such projects, the degree of improvement has to be ascertained to confirm whether the soil has achieved the required degree of consolidation before the removal of surcharge. This analysis can be carried out by means of observational methods for which the ground behaviour is continuously monitored from the date of instrument installation. This paper provides a case study of the applications of geotechnical instrumentation for construction control in the Changi East reclamation project in the Republic of Singapore. Field instruments adopted in this project included settlement plates, deep settlement gauges, earth pressure cells, pneumatic piezometers, electric piezometers and water standpi...","PeriodicalId":45150,"journal":{"name":"Geotechnical Engineering","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2009-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1680/GENG.2009.162.1.33","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67402105","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2008-02-01DOI: 10.1680/GENG.2008.161.1.3
K. Northmore, I. Jefferson, P. Jackson, D. Entwisle, A. Milodowski, M. Raines, D. Gunn, D. Boardman, A. Zourmpakis, L. M. Nelder, C. Rogers, N. Dixon, I. Smalley
A detailed site characterisation was undertaken in order to assess methods that could be used to determine the depth and lateral extent of a potentially collapsible loessic brickearth deposit at a site in Kent. The investigation presented in this paper covers both geotechnical and geophysical evaluations, correlated to detailed lithological logs of trial pits at the site. This enabled cone penetrometer profiles to be compared directly with a suite of rapid geophysical survey techniques, which included electromagnetic (EM31 and EM34), electrical resistivity surveys and shear wave profiles, calibrated against the same soil profile. From this it was possible to determine the variability and extent of a collapsible loessic soil across the entire test site, thus demonstrating that appropriately calibrated geophysical techniques can provide a rapid indication of the presence at depth of a potentially unstable soil.
{"title":"On-site characterisation of loessic deposits in Kent, UK","authors":"K. Northmore, I. Jefferson, P. Jackson, D. Entwisle, A. Milodowski, M. Raines, D. Gunn, D. Boardman, A. Zourmpakis, L. M. Nelder, C. Rogers, N. Dixon, I. Smalley","doi":"10.1680/GENG.2008.161.1.3","DOIUrl":"https://doi.org/10.1680/GENG.2008.161.1.3","url":null,"abstract":"A detailed site characterisation was undertaken in order to assess methods that could be used to determine the depth and lateral extent of a potentially collapsible loessic brickearth deposit at a site in Kent. The investigation presented in this paper covers both geotechnical and geophysical evaluations, correlated to detailed lithological logs of trial pits at the site. This enabled cone penetrometer profiles to be compared directly with a suite of rapid geophysical survey techniques, which included electromagnetic (EM31 and EM34), electrical resistivity surveys and shear wave profiles, calibrated against the same soil profile. From this it was possible to determine the variability and extent of a collapsible loessic soil across the entire test site, thus demonstrating that appropriately calibrated geophysical techniques can provide a rapid indication of the presence at depth of a potentially unstable soil.","PeriodicalId":45150,"journal":{"name":"Geotechnical Engineering","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2008-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1680/GENG.2008.161.1.3","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67402096","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2007-07-01DOI: 10.1680/GENG.2007.160.3.169
M. Burrow, A. Chan, A. Shein
The falling weight deflectometer (FWD) device is used in the UK for the dynamic testing of ballasted railway track. Using the deflection data obtained from the test, elastic modulus values of the track substructure required to build a numerical model of the track can be determined using a procedure known as back-analysis. The numerical model so calibrated can be used to determine the effect of the traffic loads on the stresses, strains and deformations in the railway track system, and is an important component of an analytical approach to track substructure design. In this paper, the use of dynamic finite-element analysis to back-analyse the material properties of the railway substructure from FWD deflection data has been demonstrated by means of an example. The numerical approach presented is the rational method for FWD-based inverse analysis and condition evaluation of ballasted railway tracks, and becomes practicable owing to continued advances in finite-element and computer technologies.
{"title":"Deflectometer-based analysis of ballasted railway tracks","authors":"M. Burrow, A. Chan, A. Shein","doi":"10.1680/GENG.2007.160.3.169","DOIUrl":"https://doi.org/10.1680/GENG.2007.160.3.169","url":null,"abstract":"The falling weight deflectometer (FWD) device is used in the UK for the dynamic testing of ballasted railway track. Using the deflection data obtained from the test, elastic modulus values of the track substructure required to build a numerical model of the track can be determined using a procedure known as back-analysis. The numerical model so calibrated can be used to determine the effect of the traffic loads on the stresses, strains and deformations in the railway track system, and is an important component of an analytical approach to track substructure design. In this paper, the use of dynamic finite-element analysis to back-analyse the material properties of the railway substructure from FWD deflection data has been demonstrated by means of an example. The numerical approach presented is the rational method for FWD-based inverse analysis and condition evaluation of ballasted railway tracks, and becomes practicable owing to continued advances in finite-element and computer technologies.","PeriodicalId":45150,"journal":{"name":"Geotechnical Engineering","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2007-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1680/GENG.2007.160.3.169","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67402051","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2006-10-01DOI: 10.1680/GENG.2006.159.4.269
Michael Brown, A. Hyde
Limited guidance on usage and methodology is currently available to engineers for the most common rapid load pile test, known as Statnamic. In order to improve the analysis of Statnamic testing in clay soils a full-scale instrumented auger bored pile was installed and tested in glacial lodgement till. As a result, improvements have been suggested in the test methodology and analysis. The inclusion of an accelerometer at the pile head would allow direct measurement of acceleration and verification of displacement measurements and velocity calculations. High-precision optical levelling of the pile before and after test cycles would allow multiple loading cycles to be considered cumulatively with greater confidence. The separation of the laser reference source from the test pile should be sufficient to avoid surface wave disturbance.
{"title":"Some observations on Statnamic pile testing","authors":"Michael Brown, A. Hyde","doi":"10.1680/GENG.2006.159.4.269","DOIUrl":"https://doi.org/10.1680/GENG.2006.159.4.269","url":null,"abstract":"Limited guidance on usage and methodology is currently available to engineers for the most common rapid load pile test, known as Statnamic. In order to improve the analysis of Statnamic testing in clay soils a full-scale instrumented auger bored pile was installed and tested in glacial lodgement till. As a result, improvements have been suggested in the test methodology and analysis. The inclusion of an accelerometer at the pile head would allow direct measurement of acceleration and verification of displacement measurements and velocity calculations. High-precision optical levelling of the pile before and after test cycles would allow multiple loading cycles to be considered cumulatively with greater confidence. The separation of the laser reference source from the test pile should be sufficient to avoid surface wave disturbance.","PeriodicalId":45150,"journal":{"name":"Geotechnical Engineering","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2006-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1680/GENG.2006.159.4.269","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67402041","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2006-01-01DOI: 10.1680/GENG.2006.159.1.35
G. McDowell, O. Harireche, H. Konietzky, S. Brown, N. Thom
A discrete element model has been developed for geogrid-reinforced ballast. A model for unreinforced ballast has first been developed and evaluated using simulations of large-scale triaxial experiments and comparing with available data. A model for the geogrid has also been developed by bonding many small balls together to form the desired geometry and evaluated by simulating standard tests. The discrete element method (DEM) has then been used to model the interaction between ballast and geogrid by simulating pull-out tests and comparing with experimental data. The DEM simulations have been shown to predict well the peak mobilised resistance and the displacement necessary to mobilise peak pull-out force. The effect of the ratio of the geogrid aperture size to ballast particle diameter on pull-out resistance has also been investigated. The zone of influence of the geogrid has also been examined by simulating larger-scale pull-out tests in addition to cyclic triaxial tests. The method holds much promise as ...
{"title":"Discrete element modelling of geogrid-reinforced aggregates","authors":"G. McDowell, O. Harireche, H. Konietzky, S. Brown, N. Thom","doi":"10.1680/GENG.2006.159.1.35","DOIUrl":"https://doi.org/10.1680/GENG.2006.159.1.35","url":null,"abstract":"A discrete element model has been developed for geogrid-reinforced ballast. A model for unreinforced ballast has first been developed and evaluated using simulations of large-scale triaxial experiments and comparing with available data. A model for the geogrid has also been developed by bonding many small balls together to form the desired geometry and evaluated by simulating standard tests. The discrete element method (DEM) has then been used to model the interaction between ballast and geogrid by simulating pull-out tests and comparing with experimental data. The DEM simulations have been shown to predict well the peak mobilised resistance and the displacement necessary to mobilise peak pull-out force. The effect of the ratio of the geogrid aperture size to ballast particle diameter on pull-out resistance has also been investigated. The zone of influence of the geogrid has also been examined by simulating larger-scale pull-out tests in addition to cyclic triaxial tests. The method holds much promise as ...","PeriodicalId":45150,"journal":{"name":"Geotechnical Engineering","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2006-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1680/GENG.2006.159.1.35","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67402446","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2005-08-01DOI: 10.1201/9780203739501-83
K. Kassim, R. Hamir, K. Kok
Lime mix with cohesive soil has a pronounce effect on its physical and chemical properties. The soil modifies as soon as lime is mixed by changing its plasticity characteristics and particle size through cation exchange and flocculation. Stabilization on the other hand is a process which took place in a later stage after modification depending on the available lime content, mineralogy, microstructure properties and alkaline environment of the soil. The alkaline environment is essential in making the silicates and aluminates become soluble for the soil-lime reaction to take place. New cementitious compounds that crystallized with age were detected through SEM and XRD. The crystallized gels known as calcium silicate hydrate and calcium aluminate hydrate bind the soil particles thus increasing the shear strength of the soil. The strength development based on the microstructure and mineralogy aspects were studied. Tests conducted which include basic characteristics tests on soil and lime, compressive strength test, chemical tests and microstructure identification have provided the inside mechanism of soil-lime reactions and a clear understanding of lime modification and stabilization processes.
{"title":"Modification and stabilization of Malaysian cohesive soils with lime","authors":"K. Kassim, R. Hamir, K. Kok","doi":"10.1201/9780203739501-83","DOIUrl":"https://doi.org/10.1201/9780203739501-83","url":null,"abstract":"Lime mix with cohesive soil has a pronounce effect on its physical and chemical properties. The soil modifies as soon as lime is mixed by changing its plasticity characteristics and particle size through cation exchange and flocculation. Stabilization on the other hand is a process which took place in a later stage after modification depending on the available lime content, mineralogy, microstructure properties and alkaline environment of the soil. The alkaline environment is essential in making the silicates and aluminates become soluble for the soil-lime reaction to take place. New cementitious compounds that crystallized with age were detected through SEM and XRD. The crystallized gels known as calcium silicate hydrate and calcium aluminate hydrate bind the soil particles thus increasing the shear strength of the soil. The strength development based on the microstructure and mineralogy aspects were studied. Tests conducted which include basic characteristics tests on soil and lime, compressive strength test, chemical tests and microstructure identification have provided the inside mechanism of soil-lime reactions and a clear understanding of lime modification and stabilization processes.","PeriodicalId":45150,"journal":{"name":"Geotechnical Engineering","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2005-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"65937773","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2005-07-01DOI: 10.1680/GENG.2005.158.3.145
M. Sakr, M. H. Naggar, M. Nehdi
When used in harsh environments and offshore applications, conventional pile materials (such as steel, timber and concrete) are prone to costly durability problems, such as corrosion in reinforced/prestressed concrete and steel shell piles. Fibreglass-reinforced polymer (FRP) composites provide a corrosion-resistant construction material. FRP–concrete composite piles have been used successfully over the last decade in several projects for fendering applications. This paper investigates the behaviour under lateral loading of FRP composite tapered and cylindrical piles filled with self-consolidating concrete (SCC) and driven in dense sand enclosed in a pressure chamber. Seventeen pile installations were conducted using toe driving and conventional head driving. The piles were subsequently subjected to static lateral load tests. The results show that the pile taper increased its lateral capacity and enhanced its overall performance. A taper coefficient, Ktl, was introduced to account for the taper effect on ...
{"title":"Lateral behaviour of composite tapered piles in dense sand","authors":"M. Sakr, M. H. Naggar, M. Nehdi","doi":"10.1680/GENG.2005.158.3.145","DOIUrl":"https://doi.org/10.1680/GENG.2005.158.3.145","url":null,"abstract":"When used in harsh environments and offshore applications, conventional pile materials (such as steel, timber and concrete) are prone to costly durability problems, such as corrosion in reinforced/prestressed concrete and steel shell piles. Fibreglass-reinforced polymer (FRP) composites provide a corrosion-resistant construction material. FRP–concrete composite piles have been used successfully over the last decade in several projects for fendering applications. This paper investigates the behaviour under lateral loading of FRP composite tapered and cylindrical piles filled with self-consolidating concrete (SCC) and driven in dense sand enclosed in a pressure chamber. Seventeen pile installations were conducted using toe driving and conventional head driving. The piles were subsequently subjected to static lateral load tests. The results show that the pile taper increased its lateral capacity and enhanced its overall performance. A taper coefficient, Ktl, was introduced to account for the taper effect on ...","PeriodicalId":45150,"journal":{"name":"Geotechnical Engineering","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2005-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1680/GENG.2005.158.3.145","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67402300","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2005-07-01DOI: 10.1680/GENG.2005.158.3.135
G. Houlsby, B. Byrne
Suction-installed caisson foundations are being used or considered for a wide variety of offshore applications ranging from anchors for floating facilities to shallow foundations for offshore wind turbines. In the design of the caissons the installation procedure must be considered as well as the in-place performance. The scope of this paper is to consider the calculations appropriate for the installation of caissons in sands. Calculation methods are presented for determining the resistance to penetration of open-ended cylindrical caisson foundations both with and without the application of suction inside the caisson. Comparisons are made with case records. A companion paper addresses the calculation procedure for installation in clays as well as in other soils.
{"title":"Design procedures for installation of suction caissons in sand","authors":"G. Houlsby, B. Byrne","doi":"10.1680/GENG.2005.158.3.135","DOIUrl":"https://doi.org/10.1680/GENG.2005.158.3.135","url":null,"abstract":"Suction-installed caisson foundations are being used or considered for a wide variety of offshore applications ranging from anchors for floating facilities to shallow foundations for offshore wind turbines. In the design of the caissons the installation procedure must be considered as well as the in-place performance. The scope of this paper is to consider the calculations appropriate for the installation of caissons in sands. Calculation methods are presented for determining the resistance to penetration of open-ended cylindrical caisson foundations both with and without the application of suction inside the caisson. Comparisons are made with case records. A companion paper addresses the calculation procedure for installation in clays as well as in other soils.","PeriodicalId":45150,"journal":{"name":"Geotechnical Engineering","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2005-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1680/GENG.2005.158.3.135","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67402286","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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