Pub Date : 2005-01-01DOI: 10.1680/GENG.2005.158.1.15
T. Navaneethan, V. Sivakumar, S. Wheeler, I. G. Doran
Three laboratory methods of suction measurement were investigated: the pressure plate technique; measurement of positive pore water pressure after undrained isotropic loading in a triaxial cell; an...
研究了三种实验室吸力测量方法:压力板法;三轴孔室不排水各向同性加载后正孔隙水压力的测量一个……
{"title":"Assessment of suction measurements in saturated clays","authors":"T. Navaneethan, V. Sivakumar, S. Wheeler, I. G. Doran","doi":"10.1680/GENG.2005.158.1.15","DOIUrl":"https://doi.org/10.1680/GENG.2005.158.1.15","url":null,"abstract":"Three laboratory methods of suction measurement were investigated: the pressure plate technique; measurement of positive pore water pressure after undrained isotropic loading in a triaxial cell; an...","PeriodicalId":45150,"journal":{"name":"Geotechnical Engineering","volume":"158 1","pages":"15-24"},"PeriodicalIF":0.3,"publicationDate":"2005-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1680/GENG.2005.158.1.15","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67402117","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 : 2005-01-01DOI: 10.1680/GENG.158.1.25.56646
S. Gourvenec, R. Mair, M. Bolton, K. Soga
This paper reports the findings of a field study of the ground conditions around an old tunnel in London Clay at a greenfield site in Kennington, South London. Ground conditions were identified from a borehole investigation incorporating a programme of in situ pore water pressure monitoring, geotechnical testing and sampling. Additionally, laboratory classification of the samples and a suite of high-quality triaxial tests were carried out. The results of this investigation are presented and discussed in conjunction with published London Clay data. The presence of a tunnel beneath the site allowed the investigation of its influence on the local soil and groundwater conditions.
{"title":"Ground conditions around an old tunnel in London Clay","authors":"S. Gourvenec, R. Mair, M. Bolton, K. Soga","doi":"10.1680/GENG.158.1.25.56646","DOIUrl":"https://doi.org/10.1680/GENG.158.1.25.56646","url":null,"abstract":"This paper reports the findings of a field study of the ground conditions around an old tunnel in London Clay at a greenfield site in Kennington, South London. Ground conditions were identified from a borehole investigation incorporating a programme of in situ pore water pressure monitoring, geotechnical testing and sampling. Additionally, laboratory classification of the samples and a suite of high-quality triaxial tests were carried out. The results of this investigation are presented and discussed in conjunction with published London Clay data. The presence of a tunnel beneath the site allowed the investigation of its influence on the local soil and groundwater conditions.","PeriodicalId":45150,"journal":{"name":"Geotechnical Engineering","volume":"158 1","pages":"25-33"},"PeriodicalIF":0.3,"publicationDate":"2005-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67401261","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 : 2005-01-01DOI: 10.1680/GENG.158.1.3.56645
D. White, M. Bolton
The comprehensive database of load tests on closed-ended piles in sand has been re-examined to study the relationship between CPT resistance, qc, and ultimate base capacity, qb. The aim is to establish the origin of low reported values of qb/qc which contrast with continuum models that suggest qb = qc for steady deep penetration. Partial embedment of the pile tip into a hard layer underlying weak material has been accounted for by weighting qc. Partial mobilisation has been accounted for by defining failure according to a plunging criterion. When these two mechanisms are considered, the resulting values of qb/qc have a mean value of 0·90 and show no trend with pile diameter. The remaining slight underprediction of the ‘continuum’ model (qb = qc) could be attributed to the underestimation of plunging load in pile tests for which steady penetration is not reached. This exercise makes two contributions: first, it is suggested that any reduction of qc when estimating the end bearing capacity of closed-ended p...
{"title":"Comparing CPT and pile base resistance in sand","authors":"D. White, M. Bolton","doi":"10.1680/GENG.158.1.3.56645","DOIUrl":"https://doi.org/10.1680/GENG.158.1.3.56645","url":null,"abstract":"The comprehensive database of load tests on closed-ended piles in sand has been re-examined to study the relationship between CPT resistance, qc, and ultimate base capacity, qb. The aim is to establish the origin of low reported values of qb/qc which contrast with continuum models that suggest qb = qc for steady deep penetration. Partial embedment of the pile tip into a hard layer underlying weak material has been accounted for by weighting qc. Partial mobilisation has been accounted for by defining failure according to a plunging criterion. When these two mechanisms are considered, the resulting values of qb/qc have a mean value of 0·90 and show no trend with pile diameter. The remaining slight underprediction of the ‘continuum’ model (qb = qc) could be attributed to the underestimation of plunging load in pile tests for which steady penetration is not reached. This exercise makes two contributions: first, it is suggested that any reduction of qc when estimating the end bearing capacity of closed-ended p...","PeriodicalId":45150,"journal":{"name":"Geotechnical Engineering","volume":"158 1","pages":"3-14"},"PeriodicalIF":0.3,"publicationDate":"2005-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67401300","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 : 2004-10-01DOI: 10.1680/GENG.2004.157.4.173
P. Morrison, A. McNamara, T. Roberts
An 8·2m diameter, 40m deep shaft for Crossrail is being constructed below the 10m deep basement of the Moorhouse development near Moorgate in the City of London. The depth of the shaft is such that it will penetrate through stiff London Clay and will be founded at the bottom of the Lambeth Group. The shaft is being constructed after the Moorhouse structure has been completed and the design of the Moorhouse foundations places tight constraints on acceptable ground movements due to construction of the shaft. Furthermore, the shaft needs to be designed to accommodate future ground movements associated with construction of Crossrail. The paper describes the complex relationship between the foundations of Moorhouse, the draught relief shaft and the future Crossrail assets. The optimised design includes extensive slip coating and base grouting of the Moorhouse piles, a complex temporary works dewatering system around the shaft and the option to carry out additional dewatering from within the shaft during constr...
{"title":"Design and construction of a deep shaft for Crossrail","authors":"P. Morrison, A. McNamara, T. Roberts","doi":"10.1680/GENG.2004.157.4.173","DOIUrl":"https://doi.org/10.1680/GENG.2004.157.4.173","url":null,"abstract":"An 8·2m diameter, 40m deep shaft for Crossrail is being constructed below the 10m deep basement of the Moorhouse development near Moorgate in the City of London. The depth of the shaft is such that it will penetrate through stiff London Clay and will be founded at the bottom of the Lambeth Group. The shaft is being constructed after the Moorhouse structure has been completed and the design of the Moorhouse foundations places tight constraints on acceptable ground movements due to construction of the shaft. Furthermore, the shaft needs to be designed to accommodate future ground movements associated with construction of Crossrail. The paper describes the complex relationship between the foundations of Moorhouse, the draught relief shaft and the future Crossrail assets. The optimised design includes extensive slip coating and base grouting of the Moorhouse piles, a complex temporary works dewatering system around the shaft and the option to carry out additional dewatering from within the shaft during constr...","PeriodicalId":45150,"journal":{"name":"Geotechnical Engineering","volume":"157 1","pages":"173-182"},"PeriodicalIF":0.3,"publicationDate":"2004-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1680/GENG.2004.157.4.173","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67402069","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 : 2004-10-01DOI: 10.1680/GENG.2004.157.4.259
S. Yan, J. Chu
A highway was constructed in Jiangxi Province, China, through a mountainous area. Some sections of the highway went through valleys where a soft clay layer 6–8·5 m deep was encountered. A new explosive method was developed and adopted for this project. The method uses the energy of the explosion to remove the soft clay and replace it with crushed stones. Explosive charges are placed in the soil to be improved according to a specific pattern. Crushed stones are piled up next to the area where the charges are installed. The explosion creates cavities in the soil and causes the pile of crushed stones to slide into the exploded area. The detail of the method and its application to the highway project are described. The effectiveness of the method is evaluated using borehole exploration, plate load tests and groundprobing radar tests.
{"title":"A new explosive method for soil improvement","authors":"S. Yan, J. Chu","doi":"10.1680/GENG.2004.157.4.259","DOIUrl":"https://doi.org/10.1680/GENG.2004.157.4.259","url":null,"abstract":"A highway was constructed in Jiangxi Province, China, through a mountainous area. Some sections of the highway went through valleys where a soft clay layer 6–8·5 m deep was encountered. A new explosive method was developed and adopted for this project. The method uses the energy of the explosion to remove the soft clay and replace it with crushed stones. Explosive charges are placed in the soil to be improved according to a specific pattern. Crushed stones are piled up next to the area where the charges are installed. The explosion creates cavities in the soil and causes the pile of crushed stones to slide into the exploded area. The detail of the method and its application to the highway project are described. The effectiveness of the method is evaluated using borehole exploration, plate load tests and groundprobing radar tests.","PeriodicalId":45150,"journal":{"name":"Geotechnical Engineering","volume":"157 1","pages":"259-265"},"PeriodicalIF":0.3,"publicationDate":"2004-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1680/GENG.2004.157.4.259","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67402338","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 : 2004-10-01DOI: 10.1680/GENG.157.4.199.51832
J. Greenwood, J. Norris, J. Wint
Many embankments and cuttings associated with the transportation infrastructure in the UK are only marginally stable. Engineering techniques such as soil nailing, geosynthetic reinforcement, improved drainage and ground improvement by stabilisation are available to improve stability but the cost can be high. A lower cost solution may be to utilise vegetation, either self seeded or planted. The benefits and drawbacks associated with vegetation have been the subject of some debate. The problems caused by vegetation in relation to building foundations are well documented and confirm that vegetation can have very significant influences on geotechnical parameters. Appropriate properly maintained vegetation can have the same significant influence to help provide additional stability to soil slopes. This paper considers the potential engineering influences of vegetation and how it can be characterised on site within a geotechnical framework for stability assessments. The direct reinforcement available from the roots of trees and shrubs is identified as providing one of the most significant contributions to slope stability. Case studies in the UK, Greece and Italy demonstrate how results from in-situ root pull out tests may be used to estimate the potential reinforcement forces available from the roots. A scheme is presented to designate zones of influence within the soil according to the size and nature of the vegetation.
{"title":"Assessing the contribution of vegetation to slope stability","authors":"J. Greenwood, J. Norris, J. Wint","doi":"10.1680/GENG.157.4.199.51832","DOIUrl":"https://doi.org/10.1680/GENG.157.4.199.51832","url":null,"abstract":"Many embankments and cuttings associated with the transportation infrastructure in the UK are only marginally stable. Engineering techniques such as soil nailing, geosynthetic reinforcement, improved drainage and ground improvement by stabilisation are available to improve stability but the cost can be high. A lower cost solution may be to utilise vegetation, either self seeded or planted. The benefits and drawbacks associated with vegetation have been the subject of some debate. The problems caused by vegetation in relation to building foundations are well documented and confirm that vegetation can have very significant influences on geotechnical parameters. Appropriate properly maintained vegetation can have the same significant influence to help provide additional stability to soil slopes. This paper considers the potential engineering influences of vegetation and how it can be characterised on site within a geotechnical framework for stability assessments. The direct reinforcement available from the roots of trees and shrubs is identified as providing one of the most significant contributions to slope stability. Case studies in the UK, Greece and Italy demonstrate how results from in-situ root pull out tests may be used to estimate the potential reinforcement forces available from the roots. A scheme is presented to designate zones of influence within the soil according to the size and nature of the vegetation.","PeriodicalId":45150,"journal":{"name":"Geotechnical Engineering","volume":"157 1","pages":"199-207"},"PeriodicalIF":0.3,"publicationDate":"2004-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67401244","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 : 2004-10-01DOI: 10.1680/GENG.2004.157.4.165
T. Henderson, A. Pickles
This paper presents the authors' personal views on how the management of geotechnical issues can have a significant influence on the planning, design and construction of major infrastructure projects. The need for continuity of geotechnical advice throughout the lifetime of the project is emphasised with a more holistic approach favoured in place of input on discrete elements such as site investigation, instrumentation and site monitoring. Forms of contract are encouraged which promote risk sharing and a more flexible approach to the assessment of uncertainties associated with ground conditions during design and construction. The authors also highlight, by reference to their own experience and other case histories, how important lessons can be learned for future projects from observation, interpretation and documentation of construction data.
{"title":"Geotechnical management on major infrastructure projects","authors":"T. Henderson, A. Pickles","doi":"10.1680/GENG.2004.157.4.165","DOIUrl":"https://doi.org/10.1680/GENG.2004.157.4.165","url":null,"abstract":"This paper presents the authors' personal views on how the management of geotechnical issues can have a significant influence on the planning, design and construction of major infrastructure projects. The need for continuity of geotechnical advice throughout the lifetime of the project is emphasised with a more holistic approach favoured in place of input on discrete elements such as site investigation, instrumentation and site monitoring. Forms of contract are encouraged which promote risk sharing and a more flexible approach to the assessment of uncertainties associated with ground conditions during design and construction. The authors also highlight, by reference to their own experience and other case histories, how important lessons can be learned for future projects from observation, interpretation and documentation of construction data.","PeriodicalId":45150,"journal":{"name":"Geotechnical Engineering","volume":"157 1","pages":"165-171"},"PeriodicalIF":0.3,"publicationDate":"2004-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1680/GENG.2004.157.4.165","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67401588","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 : 2004-10-01DOI: 10.1680/GENG.2004.157.4.209
E. Farrell, J. Coppinger
Considerable public discussion was generated during the planning stages of a rural motorway in Ireland regarding the possible effects of the road drainage system on an ecologically important fen, which was about 5 km distant. To overcome this potential problem, a passive groundwater level control system was devised to limit the drawdown by maintaining the water levels 1·75 m above the road surface. This groundwater level corresponded approximately to the seasonal low water levels recorded in the aquifer prior to the construction of the motorway. This is achieved by constructing the motorway within a sealed cross-section with a permeable layer beneath this section, called the underdrainage system, which is connected to drains that outflow at the higher level. This underdrainage system controls the water pressures and flows beneath the sealed section. This paper presents the concept of the passive groundwater control system in a non-homogeneous glacial aquifer, and analyses the effects of this control syste...
{"title":"PASSIVE GROUNDWATER CONTROL SYSTEM FOR A MOTORWAY","authors":"E. Farrell, J. Coppinger","doi":"10.1680/GENG.2004.157.4.209","DOIUrl":"https://doi.org/10.1680/GENG.2004.157.4.209","url":null,"abstract":"Considerable public discussion was generated during the planning stages of a rural motorway in Ireland regarding the possible effects of the road drainage system on an ecologically important fen, which was about 5 km distant. To overcome this potential problem, a passive groundwater level control system was devised to limit the drawdown by maintaining the water levels 1·75 m above the road surface. This groundwater level corresponded approximately to the seasonal low water levels recorded in the aquifer prior to the construction of the motorway. This is achieved by constructing the motorway within a sealed cross-section with a permeable layer beneath this section, called the underdrainage system, which is connected to drains that outflow at the higher level. This underdrainage system controls the water pressures and flows beneath the sealed section. This paper presents the concept of the passive groundwater control system in a non-homogeneous glacial aquifer, and analyses the effects of this control syste...","PeriodicalId":45150,"journal":{"name":"Geotechnical Engineering","volume":"17 1","pages":"209-217"},"PeriodicalIF":0.3,"publicationDate":"2004-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1680/GENG.2004.157.4.209","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67402077","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 : 2004-07-01DOI: 10.1680/GENG.157.3.137.42416
D. Mckelvey, V. Sivakumar, A. Bell, J. Graham
The vibrated stone column technique is an economical and environmentally friendly process that treats weak ground to enable it to withstand low to moderate loading conditions. The performance of the treated ground depends on various parameters such as the strengths of the in-situ and backfill materials, and the spacing, length and diameter of the columns. In practice, vibrated stone columns are frequently used for settlement control. Studies have shown that columns can fail by bulging, bending, punching or shearing. These failure mechanisms are examined in this paper. The study involved a series of laboratory model tests on a consolidated clay bed. The tests were carried out using two different materials: (a) transparent material with ‘clay like’ properties, and (b) speswhite kaolin. The tests on the transparent material have, probably for the first time, permitted visual examination of deforming granular columns during loading. They have shown that bulging was significant in long columns, whereas punchin...
{"title":"Modelling vibrated stone columns in soft clay","authors":"D. Mckelvey, V. Sivakumar, A. Bell, J. Graham","doi":"10.1680/GENG.157.3.137.42416","DOIUrl":"https://doi.org/10.1680/GENG.157.3.137.42416","url":null,"abstract":"The vibrated stone column technique is an economical and environmentally friendly process that treats weak ground to enable it to withstand low to moderate loading conditions. The performance of the treated ground depends on various parameters such as the strengths of the in-situ and backfill materials, and the spacing, length and diameter of the columns. In practice, vibrated stone columns are frequently used for settlement control. Studies have shown that columns can fail by bulging, bending, punching or shearing. These failure mechanisms are examined in this paper. The study involved a series of laboratory model tests on a consolidated clay bed. The tests were carried out using two different materials: (a) transparent material with ‘clay like’ properties, and (b) speswhite kaolin. The tests on the transparent material have, probably for the first time, permitted visual examination of deforming granular columns during loading. They have shown that bulging was significant in long columns, whereas punchin...","PeriodicalId":45150,"journal":{"name":"Geotechnical Engineering","volume":"157 1","pages":"137-149"},"PeriodicalIF":0.3,"publicationDate":"2004-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67401237","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 : 2004-07-01DOI: 10.1680/GENG.2004.157.3.151
G. McDowell, W. Lim, A. Collop, R. Armitage, N. Thom
It is important to have consistent ballast testing methods that provide results reflecting the performance of different ballast materials in the railway trackbed. Extensive laboratory tests have been conducted to investigate the correlation between simple ballast index tests and box tests simulating ballast field loading conditions in a simplified and controlled manner. Ballast is tamped using a vibratory poker, which causes particles to rearrange as the level of the sleeper is raised. The index tests used include single particle crushing tests, oedometer tests, and attrition tests in a revolving drum (WAV, MDA and LAA tests), in addition to water absorption and particle shape characteristics and petrographic analysis. The attrition tests performed in a revolving drum (WAV, LAA and MDA) have been found to give the best correlations with the performance of ballast in the box tests. It is considered that this may be due to the rearrangement of particles in the box test caused by the simulated tamping.
{"title":"Comparison of ballast index tests for railway trackbeds","authors":"G. McDowell, W. Lim, A. Collop, R. Armitage, N. Thom","doi":"10.1680/GENG.2004.157.3.151","DOIUrl":"https://doi.org/10.1680/GENG.2004.157.3.151","url":null,"abstract":"It is important to have consistent ballast testing methods that provide results reflecting the performance of different ballast materials in the railway trackbed. Extensive laboratory tests have been conducted to investigate the correlation between simple ballast index tests and box tests simulating ballast field loading conditions in a simplified and controlled manner. Ballast is tamped using a vibratory poker, which causes particles to rearrange as the level of the sleeper is raised. The index tests used include single particle crushing tests, oedometer tests, and attrition tests in a revolving drum (WAV, MDA and LAA tests), in addition to water absorption and particle shape characteristics and petrographic analysis. The attrition tests performed in a revolving drum (WAV, LAA and MDA) have been found to give the best correlations with the performance of ballast in the box tests. It is considered that this may be due to the rearrangement of particles in the box test caused by the simulated tamping.","PeriodicalId":45150,"journal":{"name":"Geotechnical Engineering","volume":"157 1","pages":"151-161"},"PeriodicalIF":0.3,"publicationDate":"2004-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1680/GENG.2004.157.3.151","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67402030","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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