A. Daag, K.S. Sochayseng, Earl Joyce Arnoco, Andrew Serrano, R. Solidum
A coastal portion of the Greater Metro Manila Area, Philippines, is situated primarily on Quaternary Alluvium deposits which are likely to liquefy. Liquefaction is a hazard that occurs when loosely packed, saturated sediments at or near the ground surface lose its strength caused by an earthquake. Currently, the standard in determining a site’s soil properties and liquefaction potential is by using conventional geotechnical techniques such as the Standard Penetration Test (SPT). However, this method has disadvantages in terms of cost, logistics, and as well as workforce. The Screw Driving Sounding (SDS) test was developed to estimate equivalent SPT parameters such as N-value and Fines Content which are then used for liquefaction analysis. This paper presents the comparative analysis between SDS and SPT in selected schools in Greater Metro Manila Area, Philippines. Moreover, soil classification and site-specific liquefaction potential evaluation were also estimated using the data acquired from the SDS test. Overall, the result of the study proves that the SDS test is an effective alternative method for soil investigation and estimation of the liquefaction potential.
{"title":"The use of screw driving sounding in soil assessment in Metro Manila, Philippines","authors":"A. Daag, K.S. Sochayseng, Earl Joyce Arnoco, Andrew Serrano, R. Solidum","doi":"10.1680/jgere.22.00047","DOIUrl":"https://doi.org/10.1680/jgere.22.00047","url":null,"abstract":"A coastal portion of the Greater Metro Manila Area, Philippines, is situated primarily on Quaternary Alluvium deposits which are likely to liquefy. Liquefaction is a hazard that occurs when loosely packed, saturated sediments at or near the ground surface lose its strength caused by an earthquake. Currently, the standard in determining a site’s soil properties and liquefaction potential is by using conventional geotechnical techniques such as the Standard Penetration Test (SPT). However, this method has disadvantages in terms of cost, logistics, and as well as workforce. The Screw Driving Sounding (SDS) test was developed to estimate equivalent SPT parameters such as N-value and Fines Content which are then used for liquefaction analysis. This paper presents the comparative analysis between SDS and SPT in selected schools in Greater Metro Manila Area, Philippines. Moreover, soil classification and site-specific liquefaction potential evaluation were also estimated using the data acquired from the SDS test. Overall, the result of the study proves that the SDS test is an effective alternative method for soil investigation and estimation of the liquefaction potential.","PeriodicalId":44054,"journal":{"name":"Geotechnical Research","volume":"1 1","pages":""},"PeriodicalIF":1.9,"publicationDate":"2023-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42988206","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 : 2023-03-01DOI: 10.1680/jgere.2023.10.1.1
Md Mizanur Rahman, D. E. L. Ong
{"title":"Editorial","authors":"Md Mizanur Rahman, D. E. L. Ong","doi":"10.1680/jgere.2023.10.1.1","DOIUrl":"https://doi.org/10.1680/jgere.2023.10.1.1","url":null,"abstract":"","PeriodicalId":44054,"journal":{"name":"Geotechnical Research","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2023-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44428892","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 : 2023-03-01DOI: 10.1680/jgere.2023.10.1.46
{"title":"Award-winning paper in 2021","authors":"","doi":"10.1680/jgere.2023.10.1.46","DOIUrl":"https://doi.org/10.1680/jgere.2023.10.1.46","url":null,"abstract":"","PeriodicalId":44054,"journal":{"name":"Geotechnical Research","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135026451","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}
Slope movements are generally classified in four different phases: pre-failure, failure, post-failure and eventual reactivation. In engineering applications, the pre-failure and failure phases are usually analysed using traditional numerical techniques, such as the finite element method and the finite difference method. However, these methods are often based on the assumption of small deformations, and consequently are unsuitable for analysing the slope behaviour during the post-failure stage, since this latter is usually characterised by very large deformations. To overcome this shortcoming, the material point method (MPM) is employed in the present study. Specifically, MPM is used to perform an analysis of a landslide in sensitive clays that occurred at Saint-Jude (Québec, Canada) in 2010. To assess the accuracy of the analysis, the final profile and the displacement magnitude detected after the event are compared to those obtained by the numerical simulation. The results provided by MPM are in satisfactory agreement with field observation. The failure mechanism and the development of the failure surface within the slope are also reproduced successfully. These results also show that MPM is an attractive method to predict the kinematics of landslides in sensitive clays, requiring also a limited number of conventional geotechnical parameters as input data.
{"title":"Analysis of a landslide in sensitive clays using the material point method","authors":"A. Troncone, L. Pugliese, Andrea Parise, E. Conte","doi":"10.1680/jgere.22.00060","DOIUrl":"https://doi.org/10.1680/jgere.22.00060","url":null,"abstract":"Slope movements are generally classified in four different phases: pre-failure, failure, post-failure and eventual reactivation. In engineering applications, the pre-failure and failure phases are usually analysed using traditional numerical techniques, such as the finite element method and the finite difference method. However, these methods are often based on the assumption of small deformations, and consequently are unsuitable for analysing the slope behaviour during the post-failure stage, since this latter is usually characterised by very large deformations. To overcome this shortcoming, the material point method (MPM) is employed in the present study. Specifically, MPM is used to perform an analysis of a landslide in sensitive clays that occurred at Saint-Jude (Québec, Canada) in 2010. To assess the accuracy of the analysis, the final profile and the displacement magnitude detected after the event are compared to those obtained by the numerical simulation. The results provided by MPM are in satisfactory agreement with field observation. The failure mechanism and the development of the failure surface within the slope are also reproduced successfully. These results also show that MPM is an attractive method to predict the kinematics of landslides in sensitive clays, requiring also a limited number of conventional geotechnical parameters as input data.","PeriodicalId":44054,"journal":{"name":"Geotechnical Research","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2023-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46517401","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. Omoregie, K. Muda, D. E. L. Ong, O. Ojuri, M. K. Bakri, M. Rahman, H. F. Basri, Yong Ee Ling
Bio-cementation is a new sustainable approach that has gained popularity due to its low energy and carbon footprint compared to existing technologies for geotechnical and geoenvironmental engineering applications. Bio-cementation is a soil improvement technique that involves binding the pore space of soil particles with calcium carbonate minerals by microbially induced carbonate precipitation (MICP) and filling the soil pore space. The purpose of this article is to present a current state-of-the-art and comprehensive discussion on the development of bio-cementation for soil improvement/reinforcement. Premixing, injection, immersing, and surface percolation are identified as four distinct bio-cementation treatment techniques. Furthermore, scholars have reported employing ureolytic bacteria such as Sporosarcina pasteurii, Bacillus sphaericus, and Lysinibacillus sphaericus) isolated from corals, limestone caves, soils, waste materials, seawaters, and other sources to accomplish effective bio-cementation Some of the major issues (bacterial cultivation costs and ammonium production) that impede its industrial potential and promising remedial techniques were also discussed. This state-of-the-art review also discussed the benefits and drawbacks of bio-cementation compared to traditional approaches. The significance of enzyme-induced carbonate precipitation as a soil bio-cementation alternative to MICP was also highlighted. Finally, the sustainable procedure, bio-cementation principles, and future implications are discussed.
{"title":"Soil bio-cementation treatment strategies: state-of-the-art review","authors":"A. Omoregie, K. Muda, D. E. L. Ong, O. Ojuri, M. K. Bakri, M. Rahman, H. F. Basri, Yong Ee Ling","doi":"10.1680/jgere.22.00051","DOIUrl":"https://doi.org/10.1680/jgere.22.00051","url":null,"abstract":"Bio-cementation is a new sustainable approach that has gained popularity due to its low energy and carbon footprint compared to existing technologies for geotechnical and geoenvironmental engineering applications. Bio-cementation is a soil improvement technique that involves binding the pore space of soil particles with calcium carbonate minerals by microbially induced carbonate precipitation (MICP) and filling the soil pore space. The purpose of this article is to present a current state-of-the-art and comprehensive discussion on the development of bio-cementation for soil improvement/reinforcement. Premixing, injection, immersing, and surface percolation are identified as four distinct bio-cementation treatment techniques. Furthermore, scholars have reported employing ureolytic bacteria such as Sporosarcina pasteurii, Bacillus sphaericus, and Lysinibacillus sphaericus) isolated from corals, limestone caves, soils, waste materials, seawaters, and other sources to accomplish effective bio-cementation Some of the major issues (bacterial cultivation costs and ammonium production) that impede its industrial potential and promising remedial techniques were also discussed. This state-of-the-art review also discussed the benefits and drawbacks of bio-cementation compared to traditional approaches. The significance of enzyme-induced carbonate precipitation as a soil bio-cementation alternative to MICP was also highlighted. Finally, the sustainable procedure, bio-cementation principles, and future implications are discussed.","PeriodicalId":44054,"journal":{"name":"Geotechnical Research","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2023-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49278874","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. Omoregie, D. E. L. Ong, Phua Ye Li, Nurnajwani Senian, N. Hei, A. Esnault-Filet, K. Muda, P. M. Nissom
The process of ureolysis-driven biocementation is used to improve granular soils. The precipitation of calcium carbonate (CaCO3) crystals results from the reactions of urease generated by ureolytic bacteria and chemical reagents, which strengthen or bind soil particles together. Using a lab-based scaled physical model, this paper investigated the influence of selected spacing intervals (107 mm, 214 mm and 321 mm) on the effectiveness of biocementation via the injection-suction or ‘push-pull’ approach. Polystyrene moulds were used to create soil specimens. It was then injected with 6 cycles of the treatment solutions at the intervals stated. The compressive strengths and CaCO3 content of the biocemented soil specimens were measured after curing, as well as scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS), Fourier-transform infrared (FTIR) spectroscopy, and effluent analysis (pH and ammonium measurements). The biocemented soil specimens with different spacing intervals obtained compressive strengths of 2.53 ±1.06 to 4.2 ±2.3 MPa, while the CaCO3 contents were from 2.78 ±0.3 to 11.16 ±1.5%, respectively. The elemental compositions and bonding of CaCO3 precipitates in the biocemented soil were confirmed by EDS and FTIR spectra, while SEM micrographs revealed chip-like and irregular rhombohedral crystal forms. The results demonstrated that injection spacing had an effect on MICP-treated biocemented soil.
{"title":"Effects of push-pull injection-suction spacing on sand biocementation treatment","authors":"A. Omoregie, D. E. L. Ong, Phua Ye Li, Nurnajwani Senian, N. Hei, A. Esnault-Filet, K. Muda, P. M. Nissom","doi":"10.1680/jgere.22.00053","DOIUrl":"https://doi.org/10.1680/jgere.22.00053","url":null,"abstract":"The process of ureolysis-driven biocementation is used to improve granular soils. The precipitation of calcium carbonate (CaCO3) crystals results from the reactions of urease generated by ureolytic bacteria and chemical reagents, which strengthen or bind soil particles together. Using a lab-based scaled physical model, this paper investigated the influence of selected spacing intervals (107 mm, 214 mm and 321 mm) on the effectiveness of biocementation via the injection-suction or ‘push-pull’ approach. Polystyrene moulds were used to create soil specimens. It was then injected with 6 cycles of the treatment solutions at the intervals stated. The compressive strengths and CaCO3 content of the biocemented soil specimens were measured after curing, as well as scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS), Fourier-transform infrared (FTIR) spectroscopy, and effluent analysis (pH and ammonium measurements). The biocemented soil specimens with different spacing intervals obtained compressive strengths of 2.53 ±1.06 to 4.2 ±2.3 MPa, while the CaCO3 contents were from 2.78 ±0.3 to 11.16 ±1.5%, respectively. The elemental compositions and bonding of CaCO3 precipitates in the biocemented soil were confirmed by EDS and FTIR spectra, while SEM micrographs revealed chip-like and irregular rhombohedral crystal forms. The results demonstrated that injection spacing had an effect on MICP-treated biocemented soil.","PeriodicalId":44054,"journal":{"name":"Geotechnical Research","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2023-01-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45257789","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}
Wazir Zada, Jabir Hussain, Masood Anwar, Wajeeh Ullah, Zeeshan Ali
This paper investigates physico-mechanical and petrographic attributes of Paleocene Lockhart Limestone which is measured, sampled and described from Rumli (RUM) and Shah Allah Ditta (SAD) sections of Islamabad. Petrographic analysis delineates that the limestone is categorized mainly into mudstone and wackestone microfacies and dominant presence of the micrite matrix favors the strength of the rock, whereas; veins, microfractures and porosities adversely affect the stability of the rock. Based on the UCS and PLT analyses, limestone samples incorporating the lowest porosities partnered with bioclasts encompass the highest UCS and PLT values and vice versa. The physico-mechanical analyses reveal that the limestone aggregates are within limits of the respective standards (ASTM, AASHTO, BS and NHA) for utilization in wearing, coating, cement concrete. The limestone of both sections can be utilized for geotechnical purposes like crushed material and aggregate source. Simple regression analysis was employed and based on these correlations; the limestone of the studied formation is designated as moderately strong and recommended for road or bridge construction purposes.
本文研究了从伊斯兰堡Rumli（RUM）和Shah Allah Ditta（SAD）剖面测量、采样和描述的古新世洛克哈特石灰岩的物理力学和岩相特征。岩石学分析表明，灰岩主要分为泥岩和杂砂岩微相，泥晶岩基质的主要存在有利于岩石的强度；矿脉、微裂缝和孔隙会对岩石的稳定性产生不利影响。根据无侧限抗压强度和PLT分析，结合最低孔隙率和生物碎屑的石灰石样品包含最高的无侧限抗拉强度和PLT值，反之亦然。物理力学分析表明，石灰石骨料在耐磨性、涂层和水泥混凝土中的使用在各自标准（ASTM、AASHTO、BS和NHA）的范围内。两个部分的石灰石可用于岩土工程目的，如破碎材料和骨料来源。采用简单的回归分析，并基于这些相关性；研究地层的石灰岩被指定为中等强度，建议用于道路或桥梁建设。
{"title":"Physico-mechanical and petrographic insights of Lockhart Limestone, sections of Islamabad, Pakistan","authors":"Wazir Zada, Jabir Hussain, Masood Anwar, Wajeeh Ullah, Zeeshan Ali","doi":"10.1680/jgere.22.00007","DOIUrl":"https://doi.org/10.1680/jgere.22.00007","url":null,"abstract":"This paper investigates physico-mechanical and petrographic attributes of Paleocene Lockhart Limestone which is measured, sampled and described from Rumli (RUM) and Shah Allah Ditta (SAD) sections of Islamabad. Petrographic analysis delineates that the limestone is categorized mainly into mudstone and wackestone microfacies and dominant presence of the micrite matrix favors the strength of the rock, whereas; veins, microfractures and porosities adversely affect the stability of the rock. Based on the UCS and PLT analyses, limestone samples incorporating the lowest porosities partnered with bioclasts encompass the highest UCS and PLT values and vice versa. The physico-mechanical analyses reveal that the limestone aggregates are within limits of the respective standards (ASTM, AASHTO, BS and NHA) for utilization in wearing, coating, cement concrete. The limestone of both sections can be utilized for geotechnical purposes like crushed material and aggregate source. Simple regression analysis was employed and based on these correlations; the limestone of the studied formation is designated as moderately strong and recommended for road or bridge construction purposes.","PeriodicalId":44054,"journal":{"name":"Geotechnical Research","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2023-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45256230","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}
Pipelines are simulated in the form of a continuous beam resting on a collection of linear springs. The relationships put forth by the ASCE standard are commonly used to derive the specifications of the spring elements. Some recent studies have suggested that these relationships are accompanied by certain degree of inaccuracy. In this study, two full-scale tests were carried out on polyethylene pipes buried in sandy soil (with 120.5 and 214 mm of diameter). The pipe’s displacement along its length was recorded throughout the entire test. Then, using the ABAQUS finite element package and an optimization algorithm developed in MATLAB, a modeling approach was adopted so that the properties of the equivalent linear springs simulating the soil could be determined. This way, the displacements obtained from the experiments would have the highest level of congruence with the values derived from the numerical simulations. Using this approach, the initial stiffness and the maximum force resulted from the pipe-soil interaction have been computed and compared to the values given by the ASCE and ALA standards. The results showed that for polyethylene pipe at the condition of strike-slip faulting, these values were too smaller than the values put forth by ASCE and ALA.
{"title":"New method to evaluate the polyethylene pipe-sandy soil interaction subjected to strike-slip faulting","authors":"Milad Azin, M. T. Roudsari","doi":"10.1680/jgere.22.00010","DOIUrl":"https://doi.org/10.1680/jgere.22.00010","url":null,"abstract":"Pipelines are simulated in the form of a continuous beam resting on a collection of linear springs. The relationships put forth by the ASCE standard are commonly used to derive the specifications of the spring elements. Some recent studies have suggested that these relationships are accompanied by certain degree of inaccuracy. In this study, two full-scale tests were carried out on polyethylene pipes buried in sandy soil (with 120.5 and 214 mm of diameter). The pipe’s displacement along its length was recorded throughout the entire test. Then, using the ABAQUS finite element package and an optimization algorithm developed in MATLAB, a modeling approach was adopted so that the properties of the equivalent linear springs simulating the soil could be determined. This way, the displacements obtained from the experiments would have the highest level of congruence with the values derived from the numerical simulations. Using this approach, the initial stiffness and the maximum force resulted from the pipe-soil interaction have been computed and compared to the values given by the ASCE and ALA standards. The results showed that for polyethylene pipe at the condition of strike-slip faulting, these values were too smaller than the values put forth by ASCE and ALA.","PeriodicalId":44054,"journal":{"name":"Geotechnical Research","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2022-11-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49361957","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}
Batter piles often bearing high horizontal resistance and oblique uplift load transformed from the high-rised superstructures and the direction of oblique uplift load changes with the horizontal displacement of the superstructure. However, The working behavior of batter piles under such working condition is less understood. Therefore, a series of laboratory and numerical studies are carried out. A new type of Tactile Pressure Sensor (TPS) is also used to measure the soil pressure around pile. Three major conclusions are summarized form the results. First, the lateral response of the batter pile is affected by the loading angle, while that of the axial response is not. Second, the at rest soil pressure on the batter pile is in the “offset” state, which can be fitted by elliptic function. The pile-soil interaction below a certain depth is not affected by the pile angles and the pile can be designed as the axial uplift pile. The soil stiffness varies within 0.4L and 5D in axial and radial direction of the pile respectively. The increase of pile inclination and loading angle can reduce the stiffness degradation to a certain degree. The findings of this research can support the engineering practice in design of batter piles.
{"title":"The response and soil pressure distribution around single batter pile under the oblique uplift loading","authors":"Haibin Xu, Kaiyuan Liu, Wenlong Zhu, Zhibao Nie, Cheng-shun Xu, Xiaogang Jia","doi":"10.1680/jgere.21.00038","DOIUrl":"https://doi.org/10.1680/jgere.21.00038","url":null,"abstract":"Batter piles often bearing high horizontal resistance and oblique uplift load transformed from the high-rised superstructures and the direction of oblique uplift load changes with the horizontal displacement of the superstructure. However, The working behavior of batter piles under such working condition is less understood. Therefore, a series of laboratory and numerical studies are carried out. A new type of Tactile Pressure Sensor (TPS) is also used to measure the soil pressure around pile. Three major conclusions are summarized form the results. First, the lateral response of the batter pile is affected by the loading angle, while that of the axial response is not. Second, the at rest soil pressure on the batter pile is in the “offset” state, which can be fitted by elliptic function. The pile-soil interaction below a certain depth is not affected by the pile angles and the pile can be designed as the axial uplift pile. The soil stiffness varies within 0.4L and 5D in axial and radial direction of the pile respectively. The increase of pile inclination and loading angle can reduce the stiffness degradation to a certain degree. The findings of this research can support the engineering practice in design of batter piles.","PeriodicalId":44054,"journal":{"name":"Geotechnical Research","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2022-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43625957","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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