Pub Date : 2021-11-01DOI: 10.5604/01.3001.0015.5855
A. Baryłka
Purpose: The presented article presents a numerical analysis carried out to determine the impact of an external fire taking place on the surface of the ground on the level of stress of the trench shelter casing protected by a layer of soil. Design/methodology/approach: Numerical analysis was carried out in two stages. In the first stage, a quasi-stationary distribution of the initial temperature in the centre of the ground and the shelter casing was sought. In the second stage of the analysis, the effect of the fire was considered according to the profile of time changes in the temperature of the shelter object. Findings: We assume that the trench shelter is in an oblong shape, and the fire extends over a vast area. The area surrounding the shelter casing was treated as a material with average constant thermodynamic values. Research limitations/implications: The process related to heating and cooling the enclosure was described on the basis of the Fourier equation on heat conduction in terms of the heterogeneous nature of the material, primer and concrete. Practical implications: The use of the trench shelter model as a research element in the design of special objects. Originality/value: The methods of non-stationary temperature flow through the ground and the shelter casing used, allows for a very realistic indication of how the housing will behave under the influence of high temperature caused by an external fire. The article can be useful for designers who design underground shelters.
{"title":"Studies on the impact of external fire on the lye of the shelter housing","authors":"A. Baryłka","doi":"10.5604/01.3001.0015.5855","DOIUrl":"https://doi.org/10.5604/01.3001.0015.5855","url":null,"abstract":"Purpose: The presented article presents a numerical analysis carried out to determine the impact of an external fire taking place on the surface of the ground on the level of stress of the trench shelter casing protected by a layer of soil.\u0000Design/methodology/approach: Numerical analysis was carried out in two stages. In the first stage, a quasi-stationary distribution of the initial temperature in the centre of the ground and the shelter casing was sought. In the second stage of the analysis, the effect of the fire was considered according to the profile of time changes in the temperature of the shelter object.\u0000Findings: We assume that the trench shelter is in an oblong shape, and the fire extends over a vast area. The area surrounding the shelter casing was treated as a material with average constant thermodynamic values.\u0000Research limitations/implications: The process related to heating and cooling the enclosure was described on the basis of the Fourier equation on heat conduction in terms of the heterogeneous nature of the material, primer and concrete.\u0000Practical implications: The use of the trench shelter model as a research element in the design of special objects.\u0000Originality/value: The methods of non-stationary temperature flow through the ground and the shelter casing used, allows for a very realistic indication of how the housing will behave under the influence of high temperature caused by an external fire. The article can be useful for designers who design underground shelters.\u0000\u0000","PeriodicalId":14825,"journal":{"name":"Journal of Achievements in Materials and Manufacturing Engineering","volume":"102 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87733974","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 : 2021-10-01DOI: 10.5604/01.3001.0015.5065
V. Verma, K. Nallasivam
Purpose: The primary objective of the current study is to numerically model the steel thin-walled curved box-girder bridge and to examine its various response parameters subjected to Indian Railway loading. Design/methodology/approach: The analysis is conducted by adopting a one dimensional curved thin-walled box-beam finite beam element based on finite element methodology. The scope of the work includes a computationally efficient, three-noded, one-dimensional representation of a thin-walled box-girder bridge, which is especially desirable for its preliminary analysis and design phase, as well as a study of the static characteristics of a steel curved bridge, which is critical for interpreting its dynamic response. Findings: The analytical results computed using finite element based MATLAB coding are presented in the form of various stress resultants under the effect of various combinations of Indian Railway loads. Additionally, the variation in different response parameters due to changes in radius and span length has also been investigated. Research limitations/implications: The research is restricted to the initial design and analysis phase of box-girder bridge, where the wall thickness is small as compared to the cross-section dimensions. The current approach can be extended to future research using a different method, such as Extended finite element technique on curved bridges by varying boundary conditions and number of elements. Originality/value: The validation of the adopted finite element approach is done by solving a numerical problem, which is in excellent agreement with the previous research findings. Also, previous studies had aimed at thin-walled box girders that had been exposed to point loading, uniformly distributed loading, or highway truck loading, but no research had been done on railway loading. Moreover, no previous research had performed the static analysis on thin-walled box-girders with six different response parameters, as the current study has. Engineers will benefit greatly from the research as it will help them predict the static behaviour of the curved thin-walled girder bridge, as well as assess their free vibration and dynamic response analysis.
{"title":"Static response of curved steel thin-walled box-girder bridge subjected to Indian railway loading","authors":"V. Verma, K. Nallasivam","doi":"10.5604/01.3001.0015.5065","DOIUrl":"https://doi.org/10.5604/01.3001.0015.5065","url":null,"abstract":"Purpose: The primary objective of the current study is to numerically model the steel thin-walled curved box-girder bridge and to examine its various response parameters subjected to Indian Railway loading.\u0000Design/methodology/approach: The analysis is conducted by adopting a one dimensional curved thin-walled box-beam finite beam element based on finite element methodology. The scope of the work includes a computationally efficient, three-noded, one-dimensional representation of a thin-walled box-girder bridge, which is especially desirable for its preliminary analysis and design phase, as well as a study of the static characteristics of a steel curved bridge, which is critical for interpreting its dynamic response.\u0000Findings: The analytical results computed using finite element based MATLAB coding are presented in the form of various stress resultants under the effect of various combinations of Indian Railway loads. Additionally, the variation in different response parameters due to changes in radius and span length has also been investigated.\u0000Research limitations/implications: The research is restricted to the initial design and analysis phase of box-girder bridge, where the wall thickness is small as compared to the cross-section dimensions. The current approach can be extended to future research using a different method, such as Extended finite element technique on curved bridges by varying boundary conditions and number of elements.\u0000Originality/value: The validation of the adopted finite element approach is done by solving a numerical problem, which is in excellent agreement with the previous research findings. Also, previous studies had aimed at thin-walled box girders that had been exposed to point loading, uniformly distributed loading, or highway truck loading, but no research had been done on railway loading. Moreover, no previous research had performed the static analysis on thin-walled box-girders with six different response parameters, as the current study has. Engineers will benefit greatly from the research as it will help them predict the static behaviour of the curved thin-walled girder bridge, as well as assess their free vibration and dynamic response analysis.\u0000\u0000","PeriodicalId":14825,"journal":{"name":"Journal of Achievements in Materials and Manufacturing Engineering","volume":"31 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90372031","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 : 2021-10-01DOI: 10.5604/01.3001.0015.5066
H. M. Magid
Purpose: In this study, plasma arc cutting (PAC) is an industrial process widely used for cutting various away types of metals in several operating conditions. Design/methodology/approach: It is carried out a systematic or an authoritative inquiry to discover and examine the fact, the plasma cutting process is to establish the accuracy and the quality of the cut in this current paper assessed a good away to better the cutting process. Findings: It found that the effect of parameters on the cutting quality than on the results performed to accomplish by statistical analysis. Research limitations/implications: The objective of the present work paper is to achieve cutting parameters, thus the quality of the cutting process depends upon the plasma gas pressure, scanning speed, cutting power, and cutting height. Practical implications: The product of the plasma cutting process experimentally has been the quality of the cutting equipment that was installed to monitor kerf width quality by exam the edge roughness, kerf width, and the size of the heat-affected zone (HAZ). Originality/value: The results reveal that were technically possessed of including all the relevant characteristics, then a quality control for the cutting and describe the consequence of the process parameters.
{"title":"Experimental study of mild steel cutting process by using the plasma arc method","authors":"H. M. Magid","doi":"10.5604/01.3001.0015.5066","DOIUrl":"https://doi.org/10.5604/01.3001.0015.5066","url":null,"abstract":"Purpose: In this study, plasma arc cutting (PAC) is an industrial process widely used for cutting various away types of metals in several operating conditions.\u0000Design/methodology/approach: It is carried out a systematic or an authoritative inquiry to discover and examine the fact, the plasma cutting process is to establish the accuracy and the quality of the cut in this current paper assessed a good away to better the cutting process.\u0000Findings: It found that the effect of parameters on the cutting quality than on the results performed to accomplish by statistical analysis.\u0000Research limitations/implications: The objective of the present work paper is to achieve cutting parameters, thus the quality of the cutting process depends upon the plasma gas pressure, scanning speed, cutting power, and cutting height.\u0000Practical implications: The product of the plasma cutting process experimentally has been the quality of the cutting equipment that was installed to monitor kerf width quality by exam the edge roughness, kerf width, and the size of the heat-affected zone (HAZ).\u0000Originality/value: The results reveal that were technically possessed of including all the relevant characteristics, then a quality control for the cutting and describe the consequence of the process parameters.\u0000\u0000","PeriodicalId":14825,"journal":{"name":"Journal of Achievements in Materials and Manufacturing Engineering","volume":"22 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78189838","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 : 2021-10-01DOI: 10.5604/01.3001.0015.5064
V. Panwar, R. Dutta
Purpose: The study presents the numerical study to investigate the bearing capacity of the rectangular footing on layered sand (dense over loose) using ABAQUS software. Design/methodology/approach: Finite element analysis was used in this study to investigate the bearing capacity of the rectangular footing on layered sand and subjected to inclined load. The layered sand was having an upper layer of dense sand of varied thickness (0.25 W to 2.0 W) and lower layer was considered as loose sand of infinite thickness. The various parameters varied were friction angle of the upper dense (41° to 46°) and lower loose (31° to 36°) layer of sand and load inclination (0° to 45°), where W is the width of the rectangular footing. Findings: As the thickness ratio increased from 0.00 to 2.00, the bearing capacity increased with each load inclination. The highest and lowest bearing capacity was observed at a thickness ratio of 2.00 and 0.00 respectively. The bearing capacity decreased as the load inclination increased from 0° to 45°. The displacement contour shifted toward the centre of the footing and back toward the application of the load as the thickness ratio increased from 0.25 to 1.25 and 1.50 to 2.00, respectively. When the load inclination was increased from 0° to 30°, the bearing capacity was reduced by 54.12 % to 86.96%, and when the load inclination was 45°, the bearing capacity was reduced by 80.95 % to 95.39 %. The results of dimensionless bearing capacity compare favorably with literature with an average deviation of 13.84 %. As the load inclination was changed from 0° to 45°, the displacement contours and failure pattern shifted in the direction of load application, and the depth of influence of the displacement contours and failure pattern below the footing decreased, with the highest and lowest influence observed along the depth corresponding to 0° and 45°, respectively. The vertical settlement underneath the footing decreased as the load inclination increased, and at 45°, the vertical settlement was at its lowest. As the load inclination increased from 0° to 45°, the minimum and maximum extent of influence in the depth of the upper dense sand layer decreased, with the least and highest extent of influence in the range of 0.50 to 0.50 and 1.75 to 2.00 times the width of the rectangular footing, respectively, corresponding to a load inclination of 45° and 0° Research limitations/implications: The results presented in this paper were based on the numerical study conducted on rectangular footing having length to width ratio of 1.5 and subjected to inclined load. However, further validation of the results presented in this paper, is recommended using experimental study conducted on similar size of rectangular footing. engineers designing rectangular footings subjected to inclined load and resting on layered (dense over loose) sand. Originality/value: No numerical study of the bearing capacity of the rectangular footing under inclined loading, espec
{"title":"Bearing capacity of rectangular footing on layered sand under inclined loading","authors":"V. Panwar, R. Dutta","doi":"10.5604/01.3001.0015.5064","DOIUrl":"https://doi.org/10.5604/01.3001.0015.5064","url":null,"abstract":"Purpose: The study presents the numerical study to investigate the bearing capacity of the rectangular footing on layered sand (dense over loose) using ABAQUS software.\u0000Design/methodology/approach: Finite element analysis was used in this study to investigate the bearing capacity of the rectangular footing on layered sand and subjected to inclined load. The layered sand was having an upper layer of dense sand of varied thickness (0.25 W to 2.0 W) and lower layer was considered as loose sand of infinite thickness. The various parameters varied were friction angle of the upper dense (41° to 46°) and lower loose (31° to 36°) layer of sand and load inclination (0° to 45°), where W is the width of the rectangular footing.\u0000Findings: As the thickness ratio increased from 0.00 to 2.00, the bearing capacity increased with each load inclination. The highest and lowest bearing capacity was observed at a thickness ratio of 2.00 and 0.00 respectively. The bearing capacity decreased as the load inclination increased from 0° to 45°. The displacement contour shifted toward the centre of the footing and back toward the application of the load as the thickness ratio increased from 0.25 to 1.25 and 1.50 to 2.00, respectively. When the load inclination was increased from 0° to 30°, the bearing capacity was reduced by 54.12 % to 86.96%, and when the load inclination was 45°, the bearing capacity was reduced by 80.95 % to 95.39 %. The results of dimensionless bearing capacity compare favorably with literature with an average deviation of 13.84 %. As the load inclination was changed from 0° to 45°, the displacement contours and failure pattern shifted in the direction of load application, and the depth of influence of the displacement contours and failure pattern below the footing decreased, with the highest and lowest influence observed along the depth corresponding to 0° and 45°, respectively. The vertical settlement underneath the footing decreased as the load inclination increased, and at 45°, the vertical settlement was at its lowest. As the load inclination increased from 0° to 45°, the minimum and maximum extent of influence in the depth of the upper dense sand layer decreased, with the least and highest extent of influence in the range of 0.50 to 0.50 and 1.75 to 2.00 times the width of the rectangular footing, respectively, corresponding to a load inclination of 45° and 0°\u0000Research limitations/implications: The results presented in this paper were based on the numerical study conducted on rectangular footing having length to width ratio of 1.5 and subjected to inclined load. However, further validation of the results presented in this paper, is recommended using experimental study conducted on similar size of rectangular footing.\u0000engineers designing rectangular footings subjected to inclined load and resting on layered (dense over loose) sand.\u0000Originality/value: No numerical study of the bearing capacity of the rectangular footing under inclined loading, espec","PeriodicalId":14825,"journal":{"name":"Journal of Achievements in Materials and Manufacturing Engineering","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76197465","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 : 2021-09-01DOI: 10.5604/01.3001.0015.4795
S. Nazeer, R. Dutta
Purpose: The purpose of this study is to investigate the ultimate bearing capacity of the embedded and skirted E-shaped footing resting on two layered sand using finite element method. The analysis was carried out by using ABACUS software. Design/methodology/approach: The numerical study of the ultimate bearing capacity of the embedded and skirted E-shaped footing resting on layered sand and subjected to vertical load was carried out using finite element analysis. The layered sand was having an upper layer of loose sand of thickness H and lower layer was considered as dense sand of infinite depth. The various parameters varied were the friction angle of the upper (30° to 34°) and lower (42° to 46°) layer of sand, the skirt depth (0B, 0.25B, 0.5B and 1B), the embedment depth (0B, 0.25B, 0.5B and 1B) and the thickness (0.5B, 2B and 4B) of the upper sand layer, where B is the width of the square footing. Findings: The ultimate bearing capacity was higher for the skirted E-shaped footing followed by embedded E-shaped footing and unskirted E-shaped footing in this order for all combinations of variables studied. The improvement in the ultimate bearing capacity for the skirted E-shaped footing in comparison to the embedded E-shaped footing was in the range of 0.31 % to 61.13 %, 30.5 % to 146.31 % and 73.26 % to 282.38% corresponding to H/B ratios of 0.5, 2.0 and 4.0 respectively. The highest increase (283.38 %) was observed at φ1 =30° and φ2 =46° corresponding to H/B and Ds/B ratio of 4.0 and 1.0 respectively while the increase was lowest (0.31 %) at φ1 =34° and φ2 =46° at H/B ratio of 0.5 and Ds/B ratio of 0.5. For the skirted E-shaped footing, the lateral spread was more as in comparison to the embedded E-shaped footing. The bearing capacity of the skirted footing was equal the sum of bearing capacity of the surface footing, the skin resistance developed around the skirt surfaces and tip resistance of the skirt with coefficient of determination as 0.8739. The highest displacement was found below the unskirted and embedded E-shaped footing, and at the skirt tip in the case of the skirted E-shaped footing. Further, the displacement contours generated supports the observations of the multi-edge embedded and skirted footings regarding the ultimate bearing capacity on layered sands. Research limitations/implications: The results presented in this paper were based on the numerical study conducted on E shaped footing made from a square footing of size 1.5 m x 1.5 m. However, further validation of the results presented in this paper, is recommended using experimental study conducted on similar size E shaped footing. Practical implications: The proposed numerical study can be an advantage for the architects designing similar types of super structures requiring similar shaped footings. Originality/value: No numerical study on embedded and skirted E shaped footing resting on layered sand (loose over dense) were conducted so far. Hence, an attempt was made in
目的:采用有限元法研究两层砂基础上e型基础的极限承载力。采用ABACUS软件进行分析。设计/方法/途径:采用有限元分析方法对层状砂土上嵌入和围接的e型基础在竖向荷载作用下的极限承载力进行了数值研究。层状砂的上层为厚度为H的松散砂，下层为无限深度的致密砂。各参数分别为上砂层(30°~ 34°)和下砂层(42°~ 46°)的摩擦角、裙边深度(0B、0.25B、0.5B、1B)、埋置深度(0B、0.25B、0.5B、1B)和上砂层厚度(0.5B、2B、4B)，其中B为方基宽度。研究发现:在所有研究变量的组合中，有裙边的e型基础的极限承载力较高，其次是嵌入式e型基础和无裙边的e型基础。当H/B比分别为0.5、2.0和4.0时，裙边型e型基础的极限承载力比预埋型e型基础提高了0.31% ~ 61.13%，30.5% ~ 146.31%和73.26% ~ 282.38%。当H/B和d /B比分别为4.0和1.0时，φ1 =30°和φ2 =46°的增幅最大(283.38%);当H/B比为0.5和d /B比为0.5时，φ1 =34°和φ2 =46°的增幅最小(0.31%)。裙边型e型基础的横向扩展大于内嵌型e型基础。裙边基础承载力等于裙边基础承载力、裙边周围形成的表皮阻力和裙边尖端阻力之和，决定系数为0.8739。无裙边e型基础和预埋e型基础下部位移最大，裙边e型基础顶部位移最大。此外，生成的位移等高线支持了关于层状砂的极限承载力的多边嵌入式和围脚基础的观察结果。研究局限/启示:本文中提出的结果是基于对尺寸为1.5 m x 1.5 m的方形基础制成的E形基础进行的数值研究。但是，建议通过类似尺寸的E型基础的试验研究来进一步验证本文的结果。实际意义:所提出的数值研究可以为建筑师设计类似类型的需要类似形状基础的上层结构提供优势。独创性/价值:目前还没有对层状砂土(松散大于致密)上嵌套和围边的E形基础进行数值研究。因此，本文试图估算相同基础的承载力。
{"title":"Bearing capacity of embedded and skirted E-shaped footing on layered sand","authors":"S. Nazeer, R. Dutta","doi":"10.5604/01.3001.0015.4795","DOIUrl":"https://doi.org/10.5604/01.3001.0015.4795","url":null,"abstract":"Purpose: The purpose of this study is to investigate the ultimate bearing capacity of the embedded and skirted E-shaped footing resting on two layered sand using finite element method. The analysis was carried out by using ABACUS software.\u0000Design/methodology/approach: The numerical study of the ultimate bearing capacity of the embedded and skirted E-shaped footing resting on layered sand and subjected to vertical load was carried out using finite element analysis. The layered sand was having an upper layer of loose sand of thickness H and lower layer was considered as dense sand of infinite depth. The various parameters varied were the friction angle of the upper (30° to 34°) and lower (42° to 46°) layer of sand, the skirt depth (0B, 0.25B, 0.5B and 1B), the embedment depth (0B, 0.25B, 0.5B and 1B) and the thickness (0.5B, 2B and 4B) of the upper sand layer, where B is the width of the square footing. \u0000Findings: The ultimate bearing capacity was higher for the skirted E-shaped footing followed by embedded E-shaped footing and unskirted E-shaped footing in this order for all combinations of variables studied. The improvement in the ultimate bearing capacity for the skirted E-shaped footing in comparison to the embedded E-shaped footing was in the range of 0.31 % to 61.13 %, 30.5 % to 146.31 % and 73.26 % to 282.38% corresponding to H/B ratios of 0.5, 2.0 and 4.0 respectively. The highest increase (283.38 %) was observed at φ1 =30° and φ2 =46° corresponding to H/B and Ds/B ratio of 4.0 and 1.0 respectively while the increase was lowest (0.31 %) at φ1 =34° and φ2 =46° at H/B ratio of 0.5 and Ds/B ratio of 0.5. For the skirted E-shaped footing, the lateral spread was more as in comparison to the embedded E-shaped footing. The bearing capacity of the skirted footing was equal the sum of bearing capacity of the surface footing, the skin resistance developed around the skirt surfaces and tip resistance of the skirt with coefficient of determination as 0.8739. The highest displacement was found below the unskirted and embedded E-shaped footing, and at the skirt tip in the case of the skirted E-shaped footing. Further, the displacement contours generated supports the observations of the multi-edge embedded and skirted footings regarding the ultimate bearing capacity on layered sands.\u0000Research limitations/implications: The results presented in this paper were based on the numerical study conducted on E shaped footing made from a square footing of size 1.5 m x 1.5 m. However, further validation of the results presented in this paper, is recommended using experimental study conducted on similar size E shaped footing. \u0000Practical implications: The proposed numerical study can be an advantage for the architects designing similar types of super structures requiring similar shaped footings. \u0000Originality/value: No numerical study on embedded and skirted E shaped footing resting on layered sand (loose over dense) were conducted so far. Hence, an attempt was made in","PeriodicalId":14825,"journal":{"name":"Journal of Achievements in Materials and Manufacturing Engineering","volume":"51 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84365228","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 : 2021-09-01DOI: 10.5604/01.3001.0015.4796
M. Razzaq, A. Abood
Purpose: This paper aims to investigate the effect of arc stud welding (ASW) process parameters on the microstructure and mechanical properties of AA6061-T6 and AA5086-H116 joint. Design/methodology/approach: ASW process was done with argon as a shielding gas. Optical microscope (OM), scanning electron microscope (SEM), and X-Ray Diffraction (XRD) were employed to investigate the influence of welding current, welding time, and gas flow-rate on the microstructure of the fusion zone (FZ). Torque strength and Microhardness tests were used to evaluate the mechanical properties of the welded joints. Findings: OM and SEM showed a cellular dendritic structure with equiaxed zone and columnar dendritic are forming at welding zone and weld interface. XRD analysis showed the precipitation of Mg2Si and Al3Mg2 in the similar and dissimilar joints. Similar ASW of AA6061-T6/AA6061-T6 recorded 19 N.m torque strength, while dissimilar welding of AA6061-T6/AA5086-H116 registered 23 N.m. With increasing heat input, grains in Fusion Zone (FZ) and Heat Affected Zone (HAZ) coarsen and the hardness in both zones decreased. The hardness of similar weldments indicated a remarkable softening of FZ, while lower hardness values were registered in HAZ of dissimilar weldments. Softening of both weldments is due to the dissolution of the strengthening precipitates. Hot cracks exist with similar weldments, while no cracks evidence with dissimilar weldments. Research limitations/implications: The main challenge in this work was how to minimize porosity level and how to avoid hot crack in the FZ. Practical implications: The application of ASW with ceramic ferrule has an important role in different production areas such as; automobile industry, aircraft applications, and appliances industry. Originality/value: Study the effect of welding current, welding time, and gas flow-rate of ASW process on microstructure and mechanical properties of AA6061-T6 and AA5086-H116 joint.
{"title":"Effect of arc stud welding parameters on the microstructure and mechanical properties of AA6061 and AA5086 aluminium alloys","authors":"M. Razzaq, A. Abood","doi":"10.5604/01.3001.0015.4796","DOIUrl":"https://doi.org/10.5604/01.3001.0015.4796","url":null,"abstract":"Purpose: This paper aims to investigate the effect of arc stud welding (ASW) process parameters on the microstructure and mechanical properties of AA6061-T6 and AA5086-H116 joint.\u0000Design/methodology/approach: ASW process was done with argon as a shielding gas. Optical microscope (OM), scanning electron microscope (SEM), and X-Ray Diffraction (XRD) were employed to investigate the influence of welding current, welding time, and gas flow-rate on the microstructure of the fusion zone (FZ). Torque strength and Microhardness tests were used to evaluate the mechanical properties of the welded joints.\u0000Findings: OM and SEM showed a cellular dendritic structure with equiaxed zone and columnar dendritic are forming at welding zone and weld interface. XRD analysis showed the precipitation of Mg2Si and Al3Mg2 in the similar and dissimilar joints. Similar ASW of AA6061-T6/AA6061-T6 recorded 19 N.m torque strength, while dissimilar welding of AA6061-T6/AA5086-H116 registered 23 N.m. With increasing heat input, grains in Fusion Zone (FZ) and Heat Affected Zone (HAZ) coarsen and the hardness in both zones decreased. The hardness of similar weldments indicated a remarkable softening of FZ, while lower hardness values were registered in HAZ of dissimilar weldments. Softening of both weldments is due to the dissolution of the strengthening precipitates. Hot cracks exist with similar weldments, while no cracks evidence with dissimilar weldments.\u0000Research limitations/implications: The main challenge in this work was how to minimize porosity level and how to avoid hot crack in the FZ.\u0000Practical implications: The application of ASW with ceramic ferrule has an important role in different production areas such as; automobile industry, aircraft applications, and appliances industry. \u0000Originality/value: Study the effect of welding current, welding time, and gas flow-rate of ASW process on microstructure and mechanical properties of AA6061-T6 and AA5086-H116 joint.\u0000\u0000","PeriodicalId":14825,"journal":{"name":"Journal of Achievements in Materials and Manufacturing Engineering","volume":"36 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83153050","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 : 2021-09-01DOI: 10.5604/01.3001.0015.4797
O. Kruzhilko, N. Volodchenkova, V. Maystrenko, B. Bolibrukh, V. Kalinchyk, A. Zakora, A. Feshchenko, S. Yeremenko
Purpose: To develop a more advanced methodology, the application of which will provide an informational and computational and analytical basis for planning and implementing effective preventive measures aimed at minimizing occupational risks with limited resources, as well as in the absence of organizational and technical capabilities to create absolutely safe working conditions Design/methodology/approach: For the study, statistical data were used that obtained from enterprises of the metallurgical industry of Ukraine. Research methods: analysis and generalization of known scientific results, methods of statistical analysis, mathematical modelling, expert assessments and decision theory. Findings: The results of experimental studies have confirmed the possibility of an objective assessment of various options for the OSH management strategy, which allows justifying the allocation of funds for OSH in the required amounts. It is shown that professional risk management strategies are characterized by different efficiency in the use of available financial resources, and the most effective strategy is one that allows you to minimize the level of risk (in comparison with other strategies) with the same amount of funding. Research limitations/implications: The study focuses on enterprises of the metallurgical industry in Ukraine. Practical implications: The application of the developed mathematical models demonstrates the effectiveness of financing certain preventive and protective measures, and stimulates the head to ensure industrial safety. Originality/value: The developed mathematical models allow justifying the allocation of funds for OSH in the required amounts.
{"title":"Mathematical modelling of professional risk at Ukrainian metallurgical industry enterprises","authors":"O. Kruzhilko, N. Volodchenkova, V. Maystrenko, B. Bolibrukh, V. Kalinchyk, A. Zakora, A. Feshchenko, S. Yeremenko","doi":"10.5604/01.3001.0015.4797","DOIUrl":"https://doi.org/10.5604/01.3001.0015.4797","url":null,"abstract":"Purpose: To develop a more advanced methodology, the application of which will provide an informational and computational and analytical basis for planning and implementing effective preventive measures aimed at minimizing occupational risks with limited resources, as well as in the absence of organizational and technical capabilities to create absolutely safe working conditions\u0000Design/methodology/approach: For the study, statistical data were used that obtained from enterprises of the metallurgical industry of Ukraine. Research methods: analysis and generalization of known scientific results, methods of statistical analysis, mathematical modelling, expert assessments and decision theory.\u0000Findings: The results of experimental studies have confirmed the possibility of an objective assessment of various options for the OSH management strategy, which allows justifying the allocation of funds for OSH in the required amounts. It is shown that professional risk management strategies are characterized by different efficiency in the use of available financial resources, and the most effective strategy is one that allows you to minimize the level of risk (in comparison with other strategies) with the same amount of funding.\u0000Research limitations/implications: The study focuses on enterprises of the metallurgical industry in Ukraine.\u0000Practical implications: The application of the developed mathematical models demonstrates the effectiveness of financing certain preventive and protective measures, and stimulates the head to ensure industrial safety.\u0000Originality/value: The developed mathematical models allow justifying the allocation of funds for OSH in the required amounts.\u0000\u0000","PeriodicalId":14825,"journal":{"name":"Journal of Achievements in Materials and Manufacturing Engineering","volume":"111 3-4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72470431","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 : 2021-08-01DOI: 10.5604/01.3001.0015.3585
V. Volovetskyi, Ya. Doroshenko, G. Kogut, A. P. Dzhus, I. Rybitskyi, J. I. Doroshenko, O. Shchyrba
Purpose: The article implies theoretical and experimental studies of the liquid pollution accumulations impact on the efficiency of gathering gas pipelines operation at the Yuliivskyi oil and gas condensate production facility (OGCPF). Research of efficiency of gas pipelines cleaning by various methods. Design/methodology/approach: The research methodology consists of determining the hydraulic efficiency of gathering gas pipelines before and after cleaning of their internal cavity by different methods and comparing the obtained results, which allows to objectively evaluate the efficiency of any cleaning method. CFD simulation of gas-dynamic processes in low sections of gas pipelines with liquid contaminants. Findings: Experimental studies of cleaning efficiency in the inner cavity of the gas gathering pipelines of the Yuliivskyi OGCPF by various methods, including: supply of surfactant solution, creating a high-speed gas flow, use of foam pistons were performed. It was established that cleaning the inner cavity of gas gathering pipelines by supplying a surfactant solution leads to an increase in the coefficient of hydraulic efficiency by 2%-4.5%, creating a high-speed gas flow by 4%-7%, and under certain conditions by 8%-10 % and more. However, for two gas pipelines the use of foam pistons allowed to increase the coefficient of hydraulic efficiency from 5.7 % to 10.5 % with a multiplicity of foam from 50 to 90. be recommended for other deposits.The results of CFD simulation showed that the accumulation of liquid contaminants in the lowered sections of gas pipelines affects gas-dynamic processes and leads to pressure losses above the values provided by the technological regime. With the increase in liquid contaminants volume the pressure losses occur. Moreover, with a small amount of contamination (up to 0.006 m3), liquid contaminants do not have a significant effect on pressure loss. If the contaminants volume in the lowered section of the pipeline is greater than the specified value, the pressure loss increases by parabolic dependence. The increase in mass flow leads to an increase in the value of pressure loss at the site of liquid contamination. Moreover, the greater the mass flow, the greater the impact of its changes on the pressure loss. The CFD simulation performed made it possible not only to determine the patterns of pressure loss in places of liquid contaminants accumulation in the inner cavity of gas pipelines, but also to understand the gas-dynamic processes in such places, which is an unconditional advantage of this method over experimental. Research limitations/implications: The obtained simulation results showed that the increase in the volume of liquid contaminants in the inner cavity of gas gathering pipelines leads to an increase in pressure losses above the value provided by the technological regime. To achieve maximum cleaning of gas gathering pipelines, it is necessary to develop a new method that will combine the considered.
目的:本文对Yuliivskyioil and gas condensate production facility (OGCPF)的液体污染积聚对集输管道运行效率的影响进行了理论和实验研究。不同方法对天然气管道清洗效率的研究。设计/方法/方法:研究方法包括用不同的方法清洗内腔前后测定集气管道的水力效率，并比较得到的结果，从而可以客观地评价任何清洗方法的效率。含液体污染物输气管道低段气体动力学过程的CFD模拟。研究结果:对Yuliivskyi OGCPF集气管道内腔的清洗效率进行了实验研究，包括:提供表面活性剂溶液、形成高速气流、使用泡沫活塞等。结果表明，用表面活性剂溶液清洗集气管道内腔，可使水力效率系数提高2% ~ 4.5%，使气体高速流动提高4% ~ 7%，在一定条件下可提高8% ~ 10%以上。然而，对于两条天然气管道，泡沫活塞的使用允许将液压效率系数从5.7%提高到10.5%，泡沫倍数从50到90。推荐用于其他存款。CFD模拟结果表明，液体污染物在输气管道下段的积累影响了气体动力学过程，导致压力损失超过了技术制度提供的值。随着液体污染物体积的增大，压力损失也随之发生。此外，在少量污染(高达0.006 m3)的情况下，液体污染物对压力损失没有显著影响。当管道下段污染物体积大于规定值时，压力损失呈抛物线关系增加。质量流量的增加导致液体污染部位的压力损失值的增加。质量流量越大，其变化对压力损失的影响越大。CFD模拟不仅可以确定管道内腔液体污染物积聚处的压力损失模式，而且可以了解这些地方的气体动力学过程，这是该方法相对于实验的无条件优势。研究局限/启示:获得的模拟结果表明，气体集输管道内腔液体污染物体积的增加导致压力损失增加，超过技术制度提供的值。为了最大限度地清洁集气管道，有必要开发将所考虑的方法结合起来的新方法。实际意义:实验结果可以对集气管道内腔的清洗采取更彻底的方法，并可以提前预测集气管道水力效率的提高程度。独创性/价值:对含液体污染物的输气管道下半段气体动力学过程进行CFD模拟所得结果，对各种集气管道内腔清洗方法的有效性进行实验研究，具有独创性价值。
{"title":"Investigation of gas gathering pipelines\u0000operation efficiency and selection\u0000of improvement methods","authors":"V. Volovetskyi, Ya. Doroshenko, G. Kogut, A. P. Dzhus, I. Rybitskyi, J. I. Doroshenko, O. Shchyrba","doi":"10.5604/01.3001.0015.3585","DOIUrl":"https://doi.org/10.5604/01.3001.0015.3585","url":null,"abstract":"Purpose: The article implies theoretical and experimental studies of the liquid pollution\u0000accumulations impact on the efficiency of gathering gas pipelines operation at the Yuliivskyi\u0000oil and gas condensate production facility (OGCPF). Research of efficiency of gas pipelines\u0000cleaning by various methods.\u0000Design/methodology/approach: The research methodology consists of determining\u0000the hydraulic efficiency of gathering gas pipelines before and after cleaning of their internal\u0000cavity by different methods and comparing the obtained results, which allows to objectively\u0000evaluate the efficiency of any cleaning method. CFD simulation of gas-dynamic processes\u0000in low sections of gas pipelines with liquid contaminants.\u0000Findings: Experimental studies of cleaning efficiency in the inner cavity of the gas\u0000gathering pipelines of the Yuliivskyi OGCPF by various methods, including: supply of\u0000surfactant solution, creating a high-speed gas flow, use of foam pistons were performed.\u0000It was established that cleaning the inner cavity of gas gathering pipelines by supplying a\u0000surfactant solution leads to an increase in the coefficient of hydraulic efficiency by 2%-4.5%,\u0000creating a high-speed gas flow by 4%-7%, and under certain conditions by 8%-10 %\u0000and more. However, for two gas pipelines the use of foam pistons allowed to increase the\u0000coefficient of hydraulic efficiency from 5.7 % to 10.5 % with a multiplicity of foam from 50\u0000to 90. be recommended for other deposits.The results of CFD simulation showed that the accumulation of liquid contaminants in the\u0000lowered sections of gas pipelines affects gas-dynamic processes and leads to pressure\u0000losses above the values provided by the technological regime. With the increase in\u0000liquid contaminants volume the pressure losses occur. Moreover, with a small amount of\u0000contamination (up to 0.006 m3), liquid contaminants do not have a significant effect on\u0000pressure loss. If the contaminants volume in the lowered section of the pipeline is greater\u0000than the specified value, the pressure loss increases by parabolic dependence. The\u0000increase in mass flow leads to an increase in the value of pressure loss at the site of liquid\u0000contamination. Moreover, the greater the mass flow, the greater the impact of its changes\u0000on the pressure loss.\u0000The CFD simulation performed made it possible not only to determine the patterns of\u0000pressure loss in places of liquid contaminants accumulation in the inner cavity of gas\u0000pipelines, but also to understand the gas-dynamic processes in such places, which is an\u0000unconditional advantage of this method over experimental.\u0000Research limitations/implications: The obtained simulation results showed that the\u0000increase in the volume of liquid contaminants in the inner cavity of gas gathering pipelines\u0000leads to an increase in pressure losses above the value provided by the technological\u0000regime. To achieve maximum cleaning of gas gathering pipelines, it is necessary to develop\u0000a new method that will combine the considered.","PeriodicalId":14825,"journal":{"name":"Journal of Achievements in Materials and Manufacturing Engineering","volume":"33 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86307800","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 : 2021-08-01DOI: 10.5604/01.3001.0015.3583
M. Chomiak
Purpose: of this paper is to develop a new generation of polymer composite materials that would ensure the use of residual and serious environmental problems of polyester-glass laminate waste. Design/methodology/approach: The glass reinforced polyester waste was ground and added to produce new composites. Thermoplastic - high impact polystyrene was selected for the composite matrix. Composites containing 10, 20, 30% by weight of the filler of polyester-glass laminate powder were made. The process of extrusion and subsequent injection was used to prepare the test samples. The influence of the filler on selected properties of composites was evaluated. The physical properties of the filler as well as the processing properties of the mixture as well as the mechanical properties - impact strength and tensile strength of the obtained composites were investigated. Findings: A decrease in tensile strength and impact strength was observed along with an increase in the amount of filler. Research limitations/implications: It would be interesting to carry out further analyzes, in particular with a higher volume fraction of the filler or with a different composite structure, e.g. using PVC as a matrix. The developed research topic is a good material for the preparation of publications of a practical and scientific nature, especially useful in the research and industrial environment. Practical implications: The shredded glass-polyester waste can be used as a filler of polystyrene, however, the resulting composite could be used to produce parts with slightly less responsible functions such as artificial jewelery or toy elements. Originality/value: Obtained results are a new solution a global waste management solution for glass reinforced polyester waste, which may contribute to the sustainable development of the composite materials industry through the partial utilization of waste composites with a duroplastic matrix.
{"title":"Reuse of polyester-glass laminate waste in polymer composites","authors":"M. Chomiak","doi":"10.5604/01.3001.0015.3583","DOIUrl":"https://doi.org/10.5604/01.3001.0015.3583","url":null,"abstract":"Purpose: of this paper is to develop a new generation of polymer composite materials that\u0000would ensure the use of residual and serious environmental problems of polyester-glass\u0000laminate waste.\u0000Design/methodology/approach: The glass reinforced polyester waste was ground and\u0000added to produce new composites. Thermoplastic - high impact polystyrene was selected\u0000for the composite matrix. Composites containing 10, 20, 30% by weight of the filler of\u0000polyester-glass laminate powder were made. The process of extrusion and subsequent\u0000injection was used to prepare the test samples. The influence of the filler on selected\u0000properties of composites was evaluated. The physical properties of the filler as well as the\u0000processing properties of the mixture as well as the mechanical properties - impact strength\u0000and tensile strength of the obtained composites were investigated.\u0000Findings: A decrease in tensile strength and impact strength was observed along with an\u0000increase in the amount of filler.\u0000Research limitations/implications: It would be interesting to carry out further\u0000analyzes, in particular with a higher volume fraction of the filler or with a different composite\u0000structure, e.g. using PVC as a matrix. The developed research topic is a good material for\u0000the preparation of publications of a practical and scientific nature, especially useful in the\u0000research and industrial environment.\u0000Practical implications: The shredded glass-polyester waste can be used as a filler of\u0000polystyrene, however, the resulting composite could be used to produce parts with slightly\u0000less responsible functions such as artificial jewelery or toy elements.\u0000Originality/value: Obtained results are a new solution a global waste management solution\u0000for glass reinforced polyester waste, which may contribute to the sustainable development\u0000of the composite materials industry through the partial utilization of waste composites with\u0000a duroplastic matrix.\u0000\u0000","PeriodicalId":14825,"journal":{"name":"Journal of Achievements in Materials and Manufacturing Engineering","volume":"26 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79069457","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 : 2021-08-01DOI: 10.5604/01.3001.0015.3584
J. S. Yadav, Kamalesh Kumar, R. Dutta, A. Garg
Purpose: This study aims to study the load – settlement behaviour of circular footing rested on encased single stone column. Design/methodology/approach: The effect of vertical, horizontal and combined verticalhorizontal encasement of stone column on the load carrying capacity were examined numerically. The effect of stone column dimension (80 mm and 100 mm), length (400 mm and 500 mm), and spacing of reinforcement on the load carrying capacity and reinforcement ratio were assessed. Findings: The obtained results revealed that the load carrying capacity of geotextile encased stone columns are more than ordinary stone columns. For vertically encased stone columns as the diameter increases, the advantage of encasement decreases. Whereas, for horizontally encased stone column and combined vertical- horizontal encased stone column, the performance of encasement intensifies as the diameter of stone column increases. The improvement in the load carrying capacity of clay bed reinforced with combined verticalhorizontal encased stone columns are higher than vertical encased stone columns or horizontal encased stone column. The maximum performance of encasement was observed for VHESC1 of D = 80 mm. Research limitations/implications: For this study, the diameter of footing and stone column was kept same. The interface strength factor between stone column and clay bed was not considered. Practical implications: The encased stone column could be use improve the laod bearing capacity of weak soils. Originality/value: Many studies are available in literature regarding use of geosynthetic as vertical encasement and horizontal encasement of stone column. The study on combined effect of vertical and horizontal encasement of stone column on load carrying capacity of weak soil is very minimal. Keeping this in view, the present work was carried out.
{"title":"Influence of positions of the geotextile on\u0000the load-settlement behaviour of circular\u0000footing resting on single stone column by\u00002D Plaxis software","authors":"J. S. Yadav, Kamalesh Kumar, R. Dutta, A. Garg","doi":"10.5604/01.3001.0015.3584","DOIUrl":"https://doi.org/10.5604/01.3001.0015.3584","url":null,"abstract":"Purpose: This study aims to study the load – settlement behaviour of circular footing rested\u0000on encased single stone column.\u0000Design/methodology/approach: The effect of vertical, horizontal and combined verticalhorizontal\u0000encasement of stone column on the load carrying capacity were examined\u0000numerically. The effect of stone column dimension (80 mm and 100 mm), length (400 mm\u0000and 500 mm), and spacing of reinforcement on the load carrying capacity and reinforcement\u0000ratio were assessed.\u0000Findings: The obtained results revealed that the load carrying capacity of geotextile\u0000encased stone columns are more than ordinary stone columns. For vertically encased stone\u0000columns as the diameter increases, the advantage of encasement decreases. Whereas, for\u0000horizontally encased stone column and combined vertical- horizontal encased stone column,\u0000the performance of encasement intensifies as the diameter of stone column increases. The\u0000improvement in the load carrying capacity of clay bed reinforced with combined verticalhorizontal\u0000encased stone columns are higher than vertical encased stone columns or\u0000horizontal encased stone column. The maximum performance of encasement was observed\u0000for VHESC1 of D = 80 mm.\u0000Research limitations/implications: For this study, the diameter of footing and stone\u0000column was kept same. The interface strength factor between stone column and clay bed\u0000was not considered.\u0000Practical implications: The encased stone column could be use improve the laod\u0000bearing capacity of weak soils.\u0000Originality/value: Many studies are available in literature regarding use of geosynthetic as\u0000vertical encasement and horizontal encasement of stone column. The study on combined\u0000effect of vertical and horizontal encasement of stone column on load carrying capacity of\u0000weak soil is very minimal. Keeping this in view, the present work was carried out.\u0000\u0000","PeriodicalId":14825,"journal":{"name":"Journal of Achievements in Materials and Manufacturing Engineering","volume":"188 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72718335","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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