The Experts below are selected from a list of 114132 Experts worldwide ranked by ideXlab platform
Xiao Qing Zhou - One of the best experts on this subject based on the ideXlab platform.
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Variation of structural vibration characteristics versus non-Uniform Temperature distribution
Engineering Structures, 2011Co-Authors: Yong Xia, Ze Long Wei, Hongping Zhu, Xiao Qing ZhouAbstract:In vibration-based condition assessment exercises, it is necessary to discriminate the variation of structural properties due to environmental changes from those caused by structural damages. Some efforts have been made to correlate the structural vibration characteristics and the air Temperature or Temperatures at the structural surface. As the Temperature of an entire structure is generally non-Uniformly distributed, using the air Temperature or surface Temperatures alone may not sufficiently capture the relation between the structural responses and Temperatures. The present paper aims to investigate the variation of the structural vibration characteristics versus the non-Uniform Temperature field of the structure. Thermodynamic models are employed to estimate the Temperature at different components of the structure at different times. As the material mechanical properties are Temperature dependent, the structure can be regarded as a composite structure consisting of elements with different Young’s moduli. Consequently, the natural frequencies of the structure can be calculated with the finite element method. The procedures are repeated for different times and thus variation of the frequencies with respect to time is obtained. A simply supported RC slab was constructed and used as a proof-of-concept example. The Temperatures at different points of the slab were recorded continuously in one day, together with a series of forced modal testing to extract its modal properties. On the other hand, a finite element model was established to conduct a transient thermal analysis and estimate the Temperature distribution of the slab, which shows a good agreement with the measurement counterpart. The Temperature data at all components and thermal properties of the material were then inputted to the model to calculate the frequencies, which also matched the measured frequencies very well. Moreover, a good linear correlation between the natural frequencies measured and the structural Temperatures other than the air Temperature or surface Temperatures is observed. The present study provides a new approach to quantifying the environmental effect on the structural vibration characteristics.Department of Civil and Environmental EngineeringAuthor name used in this manuscript: You-Lin X
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variation of structural vibration characteristics versus non Uniform Temperature distribution
Engineering Structures, 2011Co-Authors: Yong Xia, Ze Long Wei, Hongping Zhu, Xiao Qing ZhouAbstract:Abstract In vibration-based condition assessment exercises, it is necessary to discriminate the variation of structural properties due to environmental changes from those caused by structural damages. Some efforts have been made to correlate the structural vibration characteristics and the air Temperature or Temperatures at the structural surface. As the Temperature of an entire structure is generally non-Uniformly distributed, using the air Temperature or surface Temperatures alone may not sufficiently capture the relation between the structural responses and Temperatures. The present paper aims to investigate the variation of the structural vibration characteristics versus the non-Uniform Temperature field of the structure. Thermodynamic models are employed to estimate the Temperature at different components of the structure at different times. As the material mechanical properties are Temperature dependent, the structure can be regarded as a composite structure consisting of elements with different Young’s moduli. Consequently, the natural frequencies of the structure can be calculated with the finite element method. The procedures are repeated for different times and thus variation of the frequencies with respect to time is obtained. A simply supported RC slab was constructed and used as a proof-of-concept example. The Temperatures at different points of the slab were recorded continuously in one day, together with a series of forced modal testing to extract its modal properties. On the other hand, a finite element model was established to conduct a transient thermal analysis and estimate the Temperature distribution of the slab, which shows a good agreement with the measurement counterpart. The Temperature data at all components and thermal properties of the material were then inputted to the model to calculate the frequencies, which also matched the measured frequencies very well. Moreover, a good linear correlation between the natural frequencies measured and the structural Temperatures other than the air Temperature or surface Temperatures is observed. The present study provides a new approach to quantifying the environmental effect on the structural vibration characteristics.
Yong Xia - One of the best experts on this subject based on the ideXlab platform.
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Variation of structural vibration characteristics versus non-Uniform Temperature distribution
Engineering Structures, 2011Co-Authors: Yong Xia, Ze Long Wei, Hongping Zhu, Xiao Qing ZhouAbstract:In vibration-based condition assessment exercises, it is necessary to discriminate the variation of structural properties due to environmental changes from those caused by structural damages. Some efforts have been made to correlate the structural vibration characteristics and the air Temperature or Temperatures at the structural surface. As the Temperature of an entire structure is generally non-Uniformly distributed, using the air Temperature or surface Temperatures alone may not sufficiently capture the relation between the structural responses and Temperatures. The present paper aims to investigate the variation of the structural vibration characteristics versus the non-Uniform Temperature field of the structure. Thermodynamic models are employed to estimate the Temperature at different components of the structure at different times. As the material mechanical properties are Temperature dependent, the structure can be regarded as a composite structure consisting of elements with different Young’s moduli. Consequently, the natural frequencies of the structure can be calculated with the finite element method. The procedures are repeated for different times and thus variation of the frequencies with respect to time is obtained. A simply supported RC slab was constructed and used as a proof-of-concept example. The Temperatures at different points of the slab were recorded continuously in one day, together with a series of forced modal testing to extract its modal properties. On the other hand, a finite element model was established to conduct a transient thermal analysis and estimate the Temperature distribution of the slab, which shows a good agreement with the measurement counterpart. The Temperature data at all components and thermal properties of the material were then inputted to the model to calculate the frequencies, which also matched the measured frequencies very well. Moreover, a good linear correlation between the natural frequencies measured and the structural Temperatures other than the air Temperature or surface Temperatures is observed. The present study provides a new approach to quantifying the environmental effect on the structural vibration characteristics.Department of Civil and Environmental EngineeringAuthor name used in this manuscript: You-Lin X
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variation of structural vibration characteristics versus non Uniform Temperature distribution
Engineering Structures, 2011Co-Authors: Yong Xia, Ze Long Wei, Hongping Zhu, Xiao Qing ZhouAbstract:Abstract In vibration-based condition assessment exercises, it is necessary to discriminate the variation of structural properties due to environmental changes from those caused by structural damages. Some efforts have been made to correlate the structural vibration characteristics and the air Temperature or Temperatures at the structural surface. As the Temperature of an entire structure is generally non-Uniformly distributed, using the air Temperature or surface Temperatures alone may not sufficiently capture the relation between the structural responses and Temperatures. The present paper aims to investigate the variation of the structural vibration characteristics versus the non-Uniform Temperature field of the structure. Thermodynamic models are employed to estimate the Temperature at different components of the structure at different times. As the material mechanical properties are Temperature dependent, the structure can be regarded as a composite structure consisting of elements with different Young’s moduli. Consequently, the natural frequencies of the structure can be calculated with the finite element method. The procedures are repeated for different times and thus variation of the frequencies with respect to time is obtained. A simply supported RC slab was constructed and used as a proof-of-concept example. The Temperatures at different points of the slab were recorded continuously in one day, together with a series of forced modal testing to extract its modal properties. On the other hand, a finite element model was established to conduct a transient thermal analysis and estimate the Temperature distribution of the slab, which shows a good agreement with the measurement counterpart. The Temperature data at all components and thermal properties of the material were then inputted to the model to calculate the frequencies, which also matched the measured frequencies very well. Moreover, a good linear correlation between the natural frequencies measured and the structural Temperatures other than the air Temperature or surface Temperatures is observed. The present study provides a new approach to quantifying the environmental effect on the structural vibration characteristics.
Deshen Chen - One of the best experts on this subject based on the ideXlab platform.
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Non-Uniform Temperature field and effects of large-span spatial truss structure under construction: Field monitoring and numerical analysis
Structures, 2021Co-Authors: Deshen Chen, Hongliang Qian, Wenjie ChenAbstract:Abstract The large-span spatial truss structure under construction can produce significant non-Uniform Temperature effect due to strong solar radiation, and it directly affects the quality of structural closure and even leads to potential safety hazards. In order to study the non-Uniform Temperature field, the steel roof of Xi'an Silk Road International Convention and Exhibition Center under construction was selected as the studied structure, the real-time Temperatures of test points and thermal boundary conditions were monitored for 30 days. The numerical simulation method of Temperature field of spatial truss structure was established considering real-time shadow effect, which can be effectively analyzed by the proposed shadow analysis algorithm. During monitoring period, the structural Temperature field under strong solar radiation is significantly non-Uniform with maximum Temperature difference between test points of 15.6℃, and the maximum Temperature rise of test point compared with atmospheric Temperature is 16.9℃. By comparison with test results, the accuracy of numerical method is verified, and the daily root mean square of error rates for all monitored members is lower than 6.5% during the monitoring period. Through the analysis of test and simulation results, the non-Uniform features of Temperature field of large-span spatial truss structure was studied. In addition, the Temperature effect was calculated for different healing times considering non-Uniform Temperature field of large-span spatial truss structure under construction. Then some construction suggestions for healing time were also given. The research method and conclusions of this paper can provide valuable references for thermal design, monitoring and control of large-span spatial truss structure.
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Non-Uniform Temperature Fields and Effects of Steel Structures: Review and Outlook
Applied Sciences, 2020Co-Authors: Deshen Chen, Hongliang QianAbstract:Due to the dynamic coupling effects of solar radiation, longwave radiation, convective heat transfer, shadows, and other factors, the Temperature field and effect of steel structures are significantly non-Uniform, differing from traditional concepts that regard the Temperature variation of steel structures as a slow and Uniform progress. This difference can hinder the correct understanding of the thermal behavior of steel structures and ignore some potential safety hazards. This paper provides a review of the studies for the non-Uniform Temperature field and effect of steel structures, and presents some outlooks on future developments on the basis of the current research situation. A summary of research on the Temperature field and effect of space structures, bridges and radio telescopes initially establishes the basic cognitive framework for this field. In addition, then, the basic principles of the numerical simulation of Temperature fields are introduced through heat transfer mechanism, and the experimental test methods of Temperature and its effects are described based on typical test cases. Finally, with a view to the future, some suggestions and opinions are provided in consideration of deficiencies in the current research status. This paper hopes to provide some valuable references for future research in this field through research summary, method introduction and outlook.
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Non-Uniform Temperature Field of Spatial Grid Structure under Construction Induced by Solar Radiation
Applied Sciences, 2020Co-Authors: Deshen Chen, Hongliang Qian, Huajie WangAbstract:The Temperature of spatial structures under construction can have a significant non-Uniform distribution induced by intense solar radiation. This Temperature distribution affects the component assembly and results in closure difficulties, potentially causing safety hazards. A spatial grid structure model was designed and subjected to Temperature field test under sunlight to study the Temperature distribution of the structure and for comparison with numerical simulation methods. The distribution characteristics and the time-varying laws were analyzed based on the test data. Then, the ray-casting algorithm was introduced to analyze the shadow influence between members, so that the Temperature distribution of the model was simulated accurately, which was verified by the test data. The results show that the spatial grid structure had an obvious non-Uniform Temperature distribution, with a maximum Temperature rise of 16 °C when compared with ambient Temperature and a maximum Temperature difference between members of 11 °C. The variation laws were gained both from the test and the numerical simulation. The numerical simulation method proposed herein can be used to calculate the shadow distribution and the Temperature field of the structure effectively. The research methods and conclusions can provide valuable references for thermal design, monitoring, and control of spatial grid structures.
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Experimental and numerical investigation on the non-Uniform Temperature distribution of thin-walled steel members under solar radiation
Thin-Walled Structures, 2018Co-Authors: Deshen Chen, Hongliang Qian, Huajie Wang, You Chen, Feng Fan, Shizhao ShenAbstract:Abstract The Temperature effect often significantly affects the performance of large-span spatial structure and even becomes one of the controlling loads. To obtain the non-Uniform Temperature field distribution of the thin-walled steel members under solar radiation and the influence rules of various factors, in this paper, experimental studies are carried out with three groups of specimens including rectangular steel tube, I-shaped steel and circular steel tube. Based on the test data, the non-Uniform Temperature field distributions considering the influence of solar radiation intensity, member size and surface coating are analyzed in detail. Then, numerical methods for the Temperature field of steel members are studied considering multiple environmental factors. The validity of the numerical method is evaluated with test results. Finally, based on the parametrical studies of the major influence factors, a simplified calculation approach is presented for practical engineering applications. The experimental study demonstrates that the non-Uniform Temperature distribution of steel members truly exists and cannot be overlooked. The numerical method for the Temperature field in this paper is effective, and the simplified calculation approach can meet the required engineering precision. The research methods and conclusions of this work can provide valuable references for thermal design, monitoring and control of steel structures.
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Non-Uniform Temperature field measurement and simulation of a radio telescope’s main reflector under solar radiation
Applied Thermal Engineering, 2017Co-Authors: Deshen Chen, Hongliang Qian, Huajie Wang, Feng Fan, Gang Zhang, Shizhao ShenAbstract:Abstract To improve the ability of deep-space exploration, many astronomers around the world are actively engaged in the construction of large-aperture and high-precision radio telescopes. The Temperature effect is one of three main factors affecting the reflector accuracy of radio telescopes. To study the daily non-Uniform Temperature field of the main reflector, experimental studies are first carried out with a 3-m-aperture radio telescope model. According to the test results for 16 working conditions, the distribution rule and time-varying regularity of the daily Temperature field are summarized initially. Next, theoretical methods for the Temperature field of the main reflector are studied considering multiple environmental parameters and self-shadows. Finally, the validity of the theoretical methods is evaluated with test results. The experimental study demonstrates that the non-Uniform Temperature distribution of the main reflector truly exists and should not be overlooked, and that the theoretical methods for the reflector Temperature field proposed in this paper are effective. The research methods and conclusions can provide valuable references for thermal design, monitoring and control of similar high-precision radio telescopes.
Hongliang Qian - One of the best experts on this subject based on the ideXlab platform.
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Non-Uniform Temperature field and effects of large-span spatial truss structure under construction: Field monitoring and numerical analysis
Structures, 2021Co-Authors: Deshen Chen, Hongliang Qian, Wenjie ChenAbstract:Abstract The large-span spatial truss structure under construction can produce significant non-Uniform Temperature effect due to strong solar radiation, and it directly affects the quality of structural closure and even leads to potential safety hazards. In order to study the non-Uniform Temperature field, the steel roof of Xi'an Silk Road International Convention and Exhibition Center under construction was selected as the studied structure, the real-time Temperatures of test points and thermal boundary conditions were monitored for 30 days. The numerical simulation method of Temperature field of spatial truss structure was established considering real-time shadow effect, which can be effectively analyzed by the proposed shadow analysis algorithm. During monitoring period, the structural Temperature field under strong solar radiation is significantly non-Uniform with maximum Temperature difference between test points of 15.6℃, and the maximum Temperature rise of test point compared with atmospheric Temperature is 16.9℃. By comparison with test results, the accuracy of numerical method is verified, and the daily root mean square of error rates for all monitored members is lower than 6.5% during the monitoring period. Through the analysis of test and simulation results, the non-Uniform features of Temperature field of large-span spatial truss structure was studied. In addition, the Temperature effect was calculated for different healing times considering non-Uniform Temperature field of large-span spatial truss structure under construction. Then some construction suggestions for healing time were also given. The research method and conclusions of this paper can provide valuable references for thermal design, monitoring and control of large-span spatial truss structure.
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Non-Uniform Temperature Fields and Effects of Steel Structures: Review and Outlook
Applied Sciences, 2020Co-Authors: Deshen Chen, Hongliang QianAbstract:Due to the dynamic coupling effects of solar radiation, longwave radiation, convective heat transfer, shadows, and other factors, the Temperature field and effect of steel structures are significantly non-Uniform, differing from traditional concepts that regard the Temperature variation of steel structures as a slow and Uniform progress. This difference can hinder the correct understanding of the thermal behavior of steel structures and ignore some potential safety hazards. This paper provides a review of the studies for the non-Uniform Temperature field and effect of steel structures, and presents some outlooks on future developments on the basis of the current research situation. A summary of research on the Temperature field and effect of space structures, bridges and radio telescopes initially establishes the basic cognitive framework for this field. In addition, then, the basic principles of the numerical simulation of Temperature fields are introduced through heat transfer mechanism, and the experimental test methods of Temperature and its effects are described based on typical test cases. Finally, with a view to the future, some suggestions and opinions are provided in consideration of deficiencies in the current research status. This paper hopes to provide some valuable references for future research in this field through research summary, method introduction and outlook.
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Non-Uniform Temperature Field of Spatial Grid Structure under Construction Induced by Solar Radiation
Applied Sciences, 2020Co-Authors: Deshen Chen, Hongliang Qian, Huajie WangAbstract:The Temperature of spatial structures under construction can have a significant non-Uniform distribution induced by intense solar radiation. This Temperature distribution affects the component assembly and results in closure difficulties, potentially causing safety hazards. A spatial grid structure model was designed and subjected to Temperature field test under sunlight to study the Temperature distribution of the structure and for comparison with numerical simulation methods. The distribution characteristics and the time-varying laws were analyzed based on the test data. Then, the ray-casting algorithm was introduced to analyze the shadow influence between members, so that the Temperature distribution of the model was simulated accurately, which was verified by the test data. The results show that the spatial grid structure had an obvious non-Uniform Temperature distribution, with a maximum Temperature rise of 16 °C when compared with ambient Temperature and a maximum Temperature difference between members of 11 °C. The variation laws were gained both from the test and the numerical simulation. The numerical simulation method proposed herein can be used to calculate the shadow distribution and the Temperature field of the structure effectively. The research methods and conclusions can provide valuable references for thermal design, monitoring, and control of spatial grid structures.
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Experimental and numerical investigation on the non-Uniform Temperature distribution of thin-walled steel members under solar radiation
Thin-Walled Structures, 2018Co-Authors: Deshen Chen, Hongliang Qian, Huajie Wang, You Chen, Feng Fan, Shizhao ShenAbstract:Abstract The Temperature effect often significantly affects the performance of large-span spatial structure and even becomes one of the controlling loads. To obtain the non-Uniform Temperature field distribution of the thin-walled steel members under solar radiation and the influence rules of various factors, in this paper, experimental studies are carried out with three groups of specimens including rectangular steel tube, I-shaped steel and circular steel tube. Based on the test data, the non-Uniform Temperature field distributions considering the influence of solar radiation intensity, member size and surface coating are analyzed in detail. Then, numerical methods for the Temperature field of steel members are studied considering multiple environmental factors. The validity of the numerical method is evaluated with test results. Finally, based on the parametrical studies of the major influence factors, a simplified calculation approach is presented for practical engineering applications. The experimental study demonstrates that the non-Uniform Temperature distribution of steel members truly exists and cannot be overlooked. The numerical method for the Temperature field in this paper is effective, and the simplified calculation approach can meet the required engineering precision. The research methods and conclusions of this work can provide valuable references for thermal design, monitoring and control of steel structures.
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Non-Uniform Temperature field measurement and simulation of a radio telescope’s main reflector under solar radiation
Applied Thermal Engineering, 2017Co-Authors: Deshen Chen, Hongliang Qian, Huajie Wang, Feng Fan, Gang Zhang, Shizhao ShenAbstract:Abstract To improve the ability of deep-space exploration, many astronomers around the world are actively engaged in the construction of large-aperture and high-precision radio telescopes. The Temperature effect is one of three main factors affecting the reflector accuracy of radio telescopes. To study the daily non-Uniform Temperature field of the main reflector, experimental studies are first carried out with a 3-m-aperture radio telescope model. According to the test results for 16 working conditions, the distribution rule and time-varying regularity of the daily Temperature field are summarized initially. Next, theoretical methods for the Temperature field of the main reflector are studied considering multiple environmental parameters and self-shadows. Finally, the validity of the theoretical methods is evaluated with test results. The experimental study demonstrates that the non-Uniform Temperature distribution of the main reflector truly exists and should not be overlooked, and that the theoretical methods for the reflector Temperature field proposed in this paper are effective. The research methods and conclusions can provide valuable references for thermal design, monitoring and control of similar high-precision radio telescopes.
Ze Long Wei - One of the best experts on this subject based on the ideXlab platform.
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Variation of structural vibration characteristics versus non-Uniform Temperature distribution
Engineering Structures, 2011Co-Authors: Yong Xia, Ze Long Wei, Hongping Zhu, Xiao Qing ZhouAbstract:In vibration-based condition assessment exercises, it is necessary to discriminate the variation of structural properties due to environmental changes from those caused by structural damages. Some efforts have been made to correlate the structural vibration characteristics and the air Temperature or Temperatures at the structural surface. As the Temperature of an entire structure is generally non-Uniformly distributed, using the air Temperature or surface Temperatures alone may not sufficiently capture the relation between the structural responses and Temperatures. The present paper aims to investigate the variation of the structural vibration characteristics versus the non-Uniform Temperature field of the structure. Thermodynamic models are employed to estimate the Temperature at different components of the structure at different times. As the material mechanical properties are Temperature dependent, the structure can be regarded as a composite structure consisting of elements with different Young’s moduli. Consequently, the natural frequencies of the structure can be calculated with the finite element method. The procedures are repeated for different times and thus variation of the frequencies with respect to time is obtained. A simply supported RC slab was constructed and used as a proof-of-concept example. The Temperatures at different points of the slab were recorded continuously in one day, together with a series of forced modal testing to extract its modal properties. On the other hand, a finite element model was established to conduct a transient thermal analysis and estimate the Temperature distribution of the slab, which shows a good agreement with the measurement counterpart. The Temperature data at all components and thermal properties of the material were then inputted to the model to calculate the frequencies, which also matched the measured frequencies very well. Moreover, a good linear correlation between the natural frequencies measured and the structural Temperatures other than the air Temperature or surface Temperatures is observed. The present study provides a new approach to quantifying the environmental effect on the structural vibration characteristics.Department of Civil and Environmental EngineeringAuthor name used in this manuscript: You-Lin X
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variation of structural vibration characteristics versus non Uniform Temperature distribution
Engineering Structures, 2011Co-Authors: Yong Xia, Ze Long Wei, Hongping Zhu, Xiao Qing ZhouAbstract:Abstract In vibration-based condition assessment exercises, it is necessary to discriminate the variation of structural properties due to environmental changes from those caused by structural damages. Some efforts have been made to correlate the structural vibration characteristics and the air Temperature or Temperatures at the structural surface. As the Temperature of an entire structure is generally non-Uniformly distributed, using the air Temperature or surface Temperatures alone may not sufficiently capture the relation between the structural responses and Temperatures. The present paper aims to investigate the variation of the structural vibration characteristics versus the non-Uniform Temperature field of the structure. Thermodynamic models are employed to estimate the Temperature at different components of the structure at different times. As the material mechanical properties are Temperature dependent, the structure can be regarded as a composite structure consisting of elements with different Young’s moduli. Consequently, the natural frequencies of the structure can be calculated with the finite element method. The procedures are repeated for different times and thus variation of the frequencies with respect to time is obtained. A simply supported RC slab was constructed and used as a proof-of-concept example. The Temperatures at different points of the slab were recorded continuously in one day, together with a series of forced modal testing to extract its modal properties. On the other hand, a finite element model was established to conduct a transient thermal analysis and estimate the Temperature distribution of the slab, which shows a good agreement with the measurement counterpart. The Temperature data at all components and thermal properties of the material were then inputted to the model to calculate the frequencies, which also matched the measured frequencies very well. Moreover, a good linear correlation between the natural frequencies measured and the structural Temperatures other than the air Temperature or surface Temperatures is observed. The present study provides a new approach to quantifying the environmental effect on the structural vibration characteristics.
