Phuc-Lam Dao, Duc Bui-Van, K. Onyelowe, A. Ebid, V. Le, I. E. Ahaneku
The effect of varying additions of metakaolin (MK) on the mechanical properties of lateritic soil to be utilized in the construction of pavement foundations has been studied. The preliminary test results show that the soil is highly plastic and lacks the sufficient mechanical ability to be used as a compacted subgrade/subbase for flexible pavement foundation. The kaolin was calcinated to form MK, which was utilized in proportions of 3%, 6%, 9%, and 12% by weight of the dry lateritic soil to stabilize it. California bearing ratio and unconfined compressive strength tests were conducted on the MK-treated lateritic soil to determine the suitability of the treated materials in the construction of compacted subgrade and / or subbase layers of flexible pavement. The stabilization test results show that MK has the potential to be utilized to strengthen the CBR and UCS of lateritic soil with a peak proportion of 6% MK by weight of dry soil beyond which the soil experiences a decline in strength formation.
{"title":"Effect of metakaolin on the mechanical properties of lateritic soil","authors":"Phuc-Lam Dao, Duc Bui-Van, K. Onyelowe, A. Ebid, V. Le, I. E. Ahaneku","doi":"10.1680/jgere.22.00046","DOIUrl":"https://doi.org/10.1680/jgere.22.00046","url":null,"abstract":"The effect of varying additions of metakaolin (MK) on the mechanical properties of lateritic soil to be utilized in the construction of pavement foundations has been studied. The preliminary test results show that the soil is highly plastic and lacks the sufficient mechanical ability to be used as a compacted subgrade/subbase for flexible pavement foundation. The kaolin was calcinated to form MK, which was utilized in proportions of 3%, 6%, 9%, and 12% by weight of the dry lateritic soil to stabilize it. California bearing ratio and unconfined compressive strength tests were conducted on the MK-treated lateritic soil to determine the suitability of the treated materials in the construction of compacted subgrade and / or subbase layers of flexible pavement. The stabilization test results show that MK has the potential to be utilized to strengthen the CBR and UCS of lateritic soil with a peak proportion of 6% MK by weight of dry soil beyond which the soil experiences a decline in strength formation.","PeriodicalId":44054,"journal":{"name":"Geotechnical Research","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2022-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48709206","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}
Mohammad Shabani Soltan Moradi, M. Azadi, H. Jahanian
If underground structures built close to the surface lie within a liquefied sand lens they will be significantly damaged in the case of a seismic event. To achieve an optimal design in terms of depth, diameter and tunnel lining thickness, it is important to consider factors such as ground subsidence, bending moment and axial forces exerted on the tunnel lining. This study intends to perform multi-objective optimization of relevant tunnel parameters within the liquefied sand lens location under seismic loads. FLAC-3D was used to model the saturated sand lens and determine changes in pore water pressure and effective tension after lens liquefaction. An artificial neural network was used to find optimal values in the genetic algorithm. All optimal design points were obtained per the target function with a revised NSGAII algorithm. The results pertaining to depth, diameter and tunnel lining thickness were in opposition to one another, as reducing ground subsidence resulted in increased bending moment and axial force exerted on the tunnel lining. According to the results, it is possible for the designer of the tunnel to use Pareto charts in order to determine the optimal values regarding tunnel depth, diameter and lining thickness within the liquefied sand lens.
{"title":"Multi-objective optimization of tunnel parameters inside a liquefied sand lens under seismic loads","authors":"Mohammad Shabani Soltan Moradi, M. Azadi, H. Jahanian","doi":"10.1680/jgere.21.00025","DOIUrl":"https://doi.org/10.1680/jgere.21.00025","url":null,"abstract":"If underground structures built close to the surface lie within a liquefied sand lens they will be significantly damaged in the case of a seismic event. To achieve an optimal design in terms of depth, diameter and tunnel lining thickness, it is important to consider factors such as ground subsidence, bending moment and axial forces exerted on the tunnel lining. This study intends to perform multi-objective optimization of relevant tunnel parameters within the liquefied sand lens location under seismic loads. FLAC-3D was used to model the saturated sand lens and determine changes in pore water pressure and effective tension after lens liquefaction. An artificial neural network was used to find optimal values in the genetic algorithm. All optimal design points were obtained per the target function with a revised NSGAII algorithm. The results pertaining to depth, diameter and tunnel lining thickness were in opposition to one another, as reducing ground subsidence resulted in increased bending moment and axial force exerted on the tunnel lining. According to the results, it is possible for the designer of the tunnel to use Pareto charts in order to determine the optimal values regarding tunnel depth, diameter and lining thickness within the liquefied sand lens.","PeriodicalId":44054,"journal":{"name":"Geotechnical Research","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2022-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49072517","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}
A clear understanding and accurate assessment of the mechanical properties of the interface between backfill material and the adjacent rock mass is paramount to a safe and economical design of cemented paste backfill (CPB) structures. With the CPB being a cementitious material, sulphate compounds prevalent in the mining environment may affect the shear characteristics of rock-CPB interface. However, there are currently no research studies on the long-term shear behaviour of the CPB-rock interface exposed to sulphate attack, although CPB often contains a relatively large amount of sulphate ions. This paper presents and discusses the findings obtained through experimental investigation of the impact of the initial sulphate concentration in CPB on the shear characteristics of the interface between rock and CPB cured for advanced ages. The obtained results show that sulphate considerably influences the long-term shear strength and behaviour of the interface. Sulphate can either negatively or positively alter the shear properties of the mature CPB-rock interface due to the competition between the processes that reduce or increase the strength at the interface. The dominant process is a function of the initial sulphate content and the curing time.
{"title":"Shear characteristics of the interface between rock and cemented tailings exposed to internal sulphate attack","authors":"K. Fang, M. Fall","doi":"10.1680/jgere.22.00017","DOIUrl":"https://doi.org/10.1680/jgere.22.00017","url":null,"abstract":"A clear understanding and accurate assessment of the mechanical properties of the interface between backfill material and the adjacent rock mass is paramount to a safe and economical design of cemented paste backfill (CPB) structures. With the CPB being a cementitious material, sulphate compounds prevalent in the mining environment may affect the shear characteristics of rock-CPB interface. However, there are currently no research studies on the long-term shear behaviour of the CPB-rock interface exposed to sulphate attack, although CPB often contains a relatively large amount of sulphate ions. This paper presents and discusses the findings obtained through experimental investigation of the impact of the initial sulphate concentration in CPB on the shear characteristics of the interface between rock and CPB cured for advanced ages. The obtained results show that sulphate considerably influences the long-term shear strength and behaviour of the interface. Sulphate can either negatively or positively alter the shear properties of the mature CPB-rock interface due to the competition between the processes that reduce or increase the strength at the interface. The dominant process is a function of the initial sulphate content and the curing time.","PeriodicalId":44054,"journal":{"name":"Geotechnical Research","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2022-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42927998","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}
Ordinary and reinforced granular columns were both tested in a laboratory to study the effect of internal reinforcing using plastic fibres which were generated through the recycling of post-consumer PET bottles. A series of vertical compression tests were undertaken to understand the impact of varying the moisture content of the silt bed and the fibre concentration. Prepared samples were vertically loaded up to a maximum compression of 50 mm and the load-vertical deformation characteristics were electronically recorded. Post testing, the deformation behaviour of the column was physically modelled using a paste of plaster of Paris to obtain the maximum bulging diameter. In general, reinforcing the granular columns enhanced the load carrying capacity, although the degree of improvement was dependent on the testing conditions. For experiments conducted on the softer silt beds, an increase in fibre content resulted in higher loading strengths. The largest enhancement was recorded in the test with wetter silt, and the fibre concentration was 0.1 %. This was equivalent to 3.5 times that which was recorded when an ordinary granular column was installed. In terms of lateral deformation, the smallest bulge was obtained in the test with the wetter silt and a fibre content of 0.025 %.
{"title":"Effects of reinforcing granular columns with fibres generated from plastic bottle waste","authors":"L. Sobhee-Beetul, D. Kalumba","doi":"10.1680/jgere.22.00013","DOIUrl":"https://doi.org/10.1680/jgere.22.00013","url":null,"abstract":"Ordinary and reinforced granular columns were both tested in a laboratory to study the effect of internal reinforcing using plastic fibres which were generated through the recycling of post-consumer PET bottles. A series of vertical compression tests were undertaken to understand the impact of varying the moisture content of the silt bed and the fibre concentration. Prepared samples were vertically loaded up to a maximum compression of 50 mm and the load-vertical deformation characteristics were electronically recorded. Post testing, the deformation behaviour of the column was physically modelled using a paste of plaster of Paris to obtain the maximum bulging diameter. In general, reinforcing the granular columns enhanced the load carrying capacity, although the degree of improvement was dependent on the testing conditions. For experiments conducted on the softer silt beds, an increase in fibre content resulted in higher loading strengths. The largest enhancement was recorded in the test with wetter silt, and the fibre concentration was 0.1 %. This was equivalent to 3.5 times that which was recorded when an ordinary granular column was installed. In terms of lateral deformation, the smallest bulge was obtained in the test with the wetter silt and a fibre content of 0.025 %.","PeriodicalId":44054,"journal":{"name":"Geotechnical Research","volume":"1 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2022-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41726251","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}
O. Mughieda, A. Alzo’ubi, Marwan Alzaylaie, Ramesh Vandanapu, Akash Sharma
In geotechnical engineering practice, it is often a challenging task to select suitable method for calculation of lateral load capacity of piles. In Dubai (United Arab Emirates), predominantly piles are rock socketed with top layers commonly medium dense to dense sand or Dubai sedimentary rock contributing to bearing lateral loads. In present study, two lateral load field test results on piles were selected and used for evaluating various methods adopted by local geotechnical engineers. The ground lithology for piles selected constitutes medium dense to dense sand for top layers, which is critical in evaluation of lateral capacity of piles. Due to simpler input requirements and quicker calculations, generally, Brom’s method or p-y non-linear analysis are adopted by local geo-engineers for lateral load analysis of piles. With advancement in computing capabilities, geotechnical engineers also adopt numerical analyses. As part of this study, various methods adopted were evaluated in terms of their advantages, limitations, and accuracy in predicting the lateral load behavior of piles. Commonly adopted methodologies like Brom’s method were found to have limitations that underestimate pile capacities resulting in overdesign of pile sizes leading to higher costs, whereas comparatively, numerical approaches predicts more accurately the lateral load behavior of piles.
{"title":"Empirical and numerical study of the static lateral response of socketed pile in Dubai sedimentary rock","authors":"O. Mughieda, A. Alzo’ubi, Marwan Alzaylaie, Ramesh Vandanapu, Akash Sharma","doi":"10.1680/jgere.22.00032","DOIUrl":"https://doi.org/10.1680/jgere.22.00032","url":null,"abstract":"In geotechnical engineering practice, it is often a challenging task to select suitable method for calculation of lateral load capacity of piles. In Dubai (United Arab Emirates), predominantly piles are rock socketed with top layers commonly medium dense to dense sand or Dubai sedimentary rock contributing to bearing lateral loads. In present study, two lateral load field test results on piles were selected and used for evaluating various methods adopted by local geotechnical engineers. The ground lithology for piles selected constitutes medium dense to dense sand for top layers, which is critical in evaluation of lateral capacity of piles. Due to simpler input requirements and quicker calculations, generally, Brom’s method or p-y non-linear analysis are adopted by local geo-engineers for lateral load analysis of piles. With advancement in computing capabilities, geotechnical engineers also adopt numerical analyses. As part of this study, various methods adopted were evaluated in terms of their advantages, limitations, and accuracy in predicting the lateral load behavior of piles. Commonly adopted methodologies like Brom’s method were found to have limitations that underestimate pile capacities resulting in overdesign of pile sizes leading to higher costs, whereas comparatively, numerical approaches predicts more accurately the lateral load behavior of piles.","PeriodicalId":44054,"journal":{"name":"Geotechnical Research","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2022-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47829492","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}
With the depletion of mineral resources in recent years, the hanging-wall orebody under the final slope needs to be extracted after opencast working. Because of the slope-free face and the special mining position, this process will lead to a significantly different strata movement compared to the traditional underground mining. DEM is a common approach to studying mining-induced strata movement considering the joint’s influence. Using DEM, this paper revealed the sensitivity of the strata movement induced by mining under the final slope to the key joint-evaluated parameters (friction angle φ and cohesion c), and obtained the strata movement characteristics under different joint strengths. The main conclusions are as follows: (1) the strata movement is more sensitive to the φ than c; (2) φ is positively associated with the strata movement angle θ, whereas there is no apparent correlation between c and the strata movement angle θ; (3) there are four primary strata failure modes and three typical strata movement processes under different joint strengths, and the mechanical analysis is given. These conclusions could benefit the back analysis of strata movement using DEM and understanding the joint impact on the strata movement induced by mining under the final slope.
{"title":"A numerical study on the strata movement induced by mining under a jointed-rock slope","authors":"Kunpeng Gao, Zhangxing Xu, Gershom Endelani Mwalupaso, Zhiyuan Cheng, Yitao Wang","doi":"10.1680/jgere.22.00021","DOIUrl":"https://doi.org/10.1680/jgere.22.00021","url":null,"abstract":"With the depletion of mineral resources in recent years, the hanging-wall orebody under the final slope needs to be extracted after opencast working. Because of the slope-free face and the special mining position, this process will lead to a significantly different strata movement compared to the traditional underground mining. DEM is a common approach to studying mining-induced strata movement considering the joint’s influence. Using DEM, this paper revealed the sensitivity of the strata movement induced by mining under the final slope to the key joint-evaluated parameters (friction angle φ and cohesion c), and obtained the strata movement characteristics under different joint strengths. The main conclusions are as follows: (1) the strata movement is more sensitive to the φ than c; (2) φ is positively associated with the strata movement angle θ, whereas there is no apparent correlation between c and the strata movement angle θ; (3) there are four primary strata failure modes and three typical strata movement processes under different joint strengths, and the mechanical analysis is given. These conclusions could benefit the back analysis of strata movement using DEM and understanding the joint impact on the strata movement induced by mining under the final slope.","PeriodicalId":44054,"journal":{"name":"Geotechnical Research","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2022-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48101940","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}
This paper describes a simplified approach based on constant volume cyclic simple shear tests with uniform sinusoidal loading that can predict failure of dry sands under general shear stress time histories. The simplified method is based on the cumulative energy hypothesis that states that the dissipated energy required by a sand sample to reach failure depends only on its initial state (Dr and σ’vo) and is independent of the characteristics of the cyclic loading applied. The proposed method uses a sand-specific multivariable regression developed using a small number of cyclic simple shear tests involving uniform sinusoidal loading without the need for advanced general cyclic loading tests. Furthermore, the regression requires only a small dataset involving one uniform cyclic simple shear test per sample initial state. The simplified method was evaluated using two comprehensive experimental studies involving two different test sands. The first dataset is an experimental program by the authors involving 20/30 Ottawa sand subjected to different cyclic loading types. The second dataset is an independent experimental program that used 0/30 Monterey sand. In both cases the simplified approach was found to yield reasonable predictions of failure of the test sands when subjected to complex and irregular shear stress loading.
{"title":"A simplified method for predicting failure of sands under general cyclic simple shear loading","authors":"G. Zavala, M. Pando, Youngjin Park, R. Aguilar","doi":"10.1680/jgere.22.00011","DOIUrl":"https://doi.org/10.1680/jgere.22.00011","url":null,"abstract":"This paper describes a simplified approach based on constant volume cyclic simple shear tests with uniform sinusoidal loading that can predict failure of dry sands under general shear stress time histories. The simplified method is based on the cumulative energy hypothesis that states that the dissipated energy required by a sand sample to reach failure depends only on its initial state (Dr and σ’vo) and is independent of the characteristics of the cyclic loading applied. The proposed method uses a sand-specific multivariable regression developed using a small number of cyclic simple shear tests involving uniform sinusoidal loading without the need for advanced general cyclic loading tests. Furthermore, the regression requires only a small dataset involving one uniform cyclic simple shear test per sample initial state. The simplified method was evaluated using two comprehensive experimental studies involving two different test sands. The first dataset is an experimental program by the authors involving 20/30 Ottawa sand subjected to different cyclic loading types. The second dataset is an independent experimental program that used 0/30 Monterey sand. In both cases the simplified approach was found to yield reasonable predictions of failure of the test sands when subjected to complex and irregular shear stress loading.","PeriodicalId":44054,"journal":{"name":"Geotechnical Research","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2022-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44150888","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}
D. Shuttle, Ferdinando Marinelli, S. Brasile, M. Jefferies, Y. H. Ong
{"title":"Discussion: Validation of computational liquefaction for tailings: Tar Island Slump","authors":"D. Shuttle, Ferdinando Marinelli, S. Brasile, M. Jefferies, Y. H. Ong","doi":"10.1680/jgere.22.00003","DOIUrl":"https://doi.org/10.1680/jgere.22.00003","url":null,"abstract":"","PeriodicalId":44054,"journal":{"name":"Geotechnical Research","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2022-01-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48615519","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}
Yaxu Liu, D. E. L. Ong, E. Oh, Zhuang Liu, Ross Hughes
Cement is commonly used as a stabilisation material in soft soil stabilisation. However, the use of cement can cause environmental issues as the production of cement results in high emission of CO2. Hence, it is essential to develop other suitable stabilisation materials to reduce the amount of cement used in the stabilisation of soft soil. Fly ash and DuraCrete® were investigated in this study to be used as partial replacements for traditional cement-only mixes. The behaviour of specimens stabilised using cement, fly ash, and DuraCrete (blended cement) under both Unconfined Compressive (UC) and Consolidated Isotropic Undrained (CIU) conditions, were investigated in this study. The experiment results proved that both fly ash and DuraCrete can be used as partial replacements of cement. Fly ash can provide the highest reduction in terms of percentage of cement. Meanwhile, DuraCrete is more cost effective, as a relatively smaller quantity of DuraCrete can replace a correspondingly larger amount of cement for a similar strength gain. The contribution of this research can provide engineers with alternative, more sustainable design mixes for soft soil stabilisation that can readily satisfy design strength requirements, while emitting relatively lesser CO2.
{"title":"Sustainable cementitious blends for strength enhancement of Queensland dredged mud","authors":"Yaxu Liu, D. E. L. Ong, E. Oh, Zhuang Liu, Ross Hughes","doi":"10.1680/jgere.21.00046","DOIUrl":"https://doi.org/10.1680/jgere.21.00046","url":null,"abstract":"Cement is commonly used as a stabilisation material in soft soil stabilisation. However, the use of cement can cause environmental issues as the production of cement results in high emission of CO2. Hence, it is essential to develop other suitable stabilisation materials to reduce the amount of cement used in the stabilisation of soft soil. Fly ash and DuraCrete® were investigated in this study to be used as partial replacements for traditional cement-only mixes. The behaviour of specimens stabilised using cement, fly ash, and DuraCrete (blended cement) under both Unconfined Compressive (UC) and Consolidated Isotropic Undrained (CIU) conditions, were investigated in this study. The experiment results proved that both fly ash and DuraCrete can be used as partial replacements of cement. Fly ash can provide the highest reduction in terms of percentage of cement. Meanwhile, DuraCrete is more cost effective, as a relatively smaller quantity of DuraCrete can replace a correspondingly larger amount of cement for a similar strength gain. The contribution of this research can provide engineers with alternative, more sustainable design mixes for soft soil stabilisation that can readily satisfy design strength requirements, while emitting relatively lesser CO2.","PeriodicalId":44054,"journal":{"name":"Geotechnical Research","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2022-01-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45908476","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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