Lijun Wang, Yongxing Dai, Zekun Chen, Huijian Zhang, Gongning Liu
In this paper, relying on the Tianhe East Station project of Guangzhou Subway Line 11, the deformation and mechanical evolution rules about the existing adjacent stations with the pile-beam-arch (PBA) method in the all excavation stages about the new foundation pit is evaluated through numerical calculation method. It was revealed that that the largest displacement about the existing station’s side wall and the middle column reaches 2.1mm and 1.5mm respectively during the excavation about the foundation pit. Due to the impact about construction of the foundation pit, the uplifting phenomenon occurs on the side of the foundation pit, and the maximum uplifting value reaches 0.4mm. When the construction about foundation pit is finished, the whole station floor shows a deformation form of “left lower torsion”, and the largest compressive stresses as well as tensile stresses about the side wall and the bottom plate do not reach the standard limiting value, and the whole is being a relative safe status. With the increase about the excavation depths, the axial forces about the middle column gradually increase to 7016kN, and the incremental axial forces about the middle column after the construction is completed accounts for about 11.7% of the axial force of initial construction. Therefore, the disturbance effect about foundation pit construction on the adjacent station with the PBA method can not be ignored. The research result in this paper may offer some important references for the construction and design of similar cases.
{"title":"Evaluation of the dynamic additional impact about foundation pit construction on the existing adjacent subway station with the PBA method","authors":"Lijun Wang, Yongxing Dai, Zekun Chen, Huijian Zhang, Gongning Liu","doi":"10.56748/ejse.23525","DOIUrl":"https://doi.org/10.56748/ejse.23525","url":null,"abstract":"In this paper, relying on the Tianhe East Station project of Guangzhou Subway Line 11, the deformation and mechanical evolution rules about the existing adjacent stations with the pile-beam-arch (PBA) method in the all excavation stages about the new foundation pit is evaluated through numerical calculation method. It was revealed that that the largest displacement about the existing station’s side wall and the middle column reaches 2.1mm and 1.5mm respectively during the excavation about the foundation pit. Due to the impact about construction of the foundation pit, the uplifting phenomenon occurs on the side of the foundation pit, and the maximum uplifting value reaches 0.4mm. When the construction about foundation pit is finished, the whole station floor shows a deformation form of “left lower torsion”, and the largest compressive stresses as well as tensile stresses about the side wall and the bottom plate do not reach the standard limiting value, and the whole is being a relative safe status. With the increase about the excavation depths, the axial forces about the middle column gradually increase to 7016kN, and the incremental axial forces about the middle column after the construction is completed accounts for about 11.7% of the axial force of initial construction. Therefore, the disturbance effect about foundation pit construction on the adjacent station with the PBA method can not be ignored. The research result in this paper may offer some important references for the construction and design of similar cases.","PeriodicalId":52513,"journal":{"name":"Electronic Journal of Structural Engineering","volume":"51 6","pages":""},"PeriodicalIF":0.6,"publicationDate":"2023-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139005094","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}
Ultra-high-performance concrete commonly known as UHPC is rising curiosity among structural engineers all over. Though early research on this material dates back to a couple of decades, some initial knowledge about this material, its behavior, and its properties is largely limited to a few research circles in a handful of advanced countries. This paper introduces UHPC as a material, elaborates on its ingredients, and describes its properties. A detailed review of available research literature about UHPC is made. The contributions made by several researchers have been discussed in detail. Following this, the structural behavior and strength of the material are reviewed comprehensively. Comparisons are made between conventional concrete and UHPC with respect to their properties, stress-strain relation, cracking behavior, compressive, tensile, and shear strengths. A detailed evaluation is made of the enhanced properties of the material with respect to its durability and long-term performance. The resistance of this material to moisture permeability, chloride ingress, and chemical attacks is understood. The impact resistance and energy absorption characteristics of the material are compared with conventional concrete. The study documented the structural applications of UHPC as well as the potential applications in the field of civil engineering. Finally, the authors enlisted the impacts of this new material (UHPC) on the future direction of structural engineering and the innovative solutions it can provide to structural engineering problems
{"title":"Ultra-High-Performance Concrete (UHPC): A state-of-the-art review of material behavior, structural applications and future","authors":"Srimaruthi Jonnalagadda, Srinivas Chava","doi":"10.56748/ejse.23426","DOIUrl":"https://doi.org/10.56748/ejse.23426","url":null,"abstract":"Ultra-high-performance concrete commonly known as UHPC is rising curiosity among structural engineers all over. Though early research on this material dates back to a couple of decades, some initial knowledge about this material, its behavior, and its properties is largely limited to a few research circles in a handful of advanced countries. This paper introduces UHPC as a material, elaborates on its ingredients, and describes its properties. A detailed review of available research literature about UHPC is made. The contributions made by several researchers have been discussed in detail. Following this, the structural behavior and strength of the material are reviewed comprehensively. Comparisons are made between conventional concrete and UHPC with respect to their properties, stress-strain relation, cracking behavior, compressive, tensile, and shear strengths. A detailed evaluation is made of the enhanced properties of the material with respect to its durability and long-term performance. The resistance of this material to moisture permeability, chloride ingress, and chemical attacks is understood. The impact resistance and energy absorption characteristics of the material are compared with conventional concrete. The study documented the structural applications of UHPC as well as the potential applications in the field of civil engineering. Finally, the authors enlisted the impacts of this new material (UHPC) on the future direction of structural engineering and the innovative solutions it can provide to structural engineering problems","PeriodicalId":52513,"journal":{"name":"Electronic Journal of Structural Engineering","volume":"58 5","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135037253","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}
El-Sayed Z. El-Bayome, Ahmed M. Abd El-Salam, Osama O. El-Mahdy, Hala.M Refaat
This paper investigates the seismic behavior of high-rise buildings having transfer elements. Three constructed reinforced concrete (RC) buildings having either transfer slabs or transfer girders were analyzed using the response spectrum (RS) and time-history (TH) methods. For each building, the story shear, bending moment, displacement, drift, and time period were obtained. Furthermore, pushover analysis (POA) method was conducted to evaluate the capability of these buildings to resist the expected seismic loads. Results of the studied buildings showed that, the base shears obtained using pushover analysis are ranging between 50% to 83% of those calculated using the static approach. In addition, the response modification factors (R) for these buildings were calculated to show their sensitivity due to the irregularity of buildings. For the studied cases in this research, the R values given in the building codes were overestimated for the cases with transfer slabs and underestimated for cases with transfer girders.
{"title":"Seismic Assessment of High-Rise Buildings Having Transfer Elements","authors":"El-Sayed Z. El-Bayome, Ahmed M. Abd El-Salam, Osama O. El-Mahdy, Hala.M Refaat","doi":"10.56748/ejse.23433","DOIUrl":"https://doi.org/10.56748/ejse.23433","url":null,"abstract":"This paper investigates the seismic behavior of high-rise buildings having transfer elements. Three constructed reinforced concrete (RC) buildings having either transfer slabs or transfer girders were analyzed using the response spectrum (RS) and time-history (TH) methods. For each building, the story shear, bending moment, displacement, drift, and time period were obtained. Furthermore, pushover analysis (POA) method was conducted to evaluate the capability of these buildings to resist the expected seismic loads. Results of the studied buildings showed that, the base shears obtained using pushover analysis are ranging between 50% to 83% of those calculated using the static approach. In addition, the response modification factors (R) for these buildings were calculated to show their sensitivity due to the irregularity of buildings. For the studied cases in this research, the R values given in the building codes were overestimated for the cases with transfer slabs and underestimated for cases with transfer girders.","PeriodicalId":52513,"journal":{"name":"Electronic Journal of Structural Engineering","volume":"65 9","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135036612","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}
Abdelmalek Abdelhamid, Baizid Benahmed, Mehmet Palanci, Lakhdar Aidaoui
Structure's damping force during an earthquake is very different from what was anticipated during design. This adds uncertainty to the process of designing structures exposed to seismic loads which may be a major cause of significant variation in the seismic response reliability of these structures. This work is focused on the investigation of the structural damping uncertainties effect on the structure’s response spectra through the assessment of uncertainties in the damping reduction factors (DRF) derived from the acceleration, velocity and displacement spectra. An Artificial Neural Networks (ANN) was also developed for the stochastic DRF calculation. The Monte Carlo method, one of the methods of computational algorithms that rely on repeated random sampling to obtain numerical results, is used for the estimation of the stochastic DRF. The obtained results indicates that the difference between the deterministic and the stochastic DRF are around of 21 % for displacement and velocity and 28.7 % for acceleration spectra. As a consequence, the DRF derived from the acceleration spectra is more sensible to the uncertainties inherent on damping than the DRF obtained from displacement and velocity. Therefore, it is important to take this conclusion into account when using these factors previously. The ANN constitutes a sample and efficiency method to predict the stochastic DRF since the error obtained is always less than 6 %. Practice oriented results are searched for, to be incorporated in future seismic standards.
{"title":"Assessment of uncertainties in damping reduction factors using ANN for acceleration, velocity and displacement spectra","authors":"Abdelmalek Abdelhamid, Baizid Benahmed, Mehmet Palanci, Lakhdar Aidaoui","doi":"10.56748/ejse.23395","DOIUrl":"https://doi.org/10.56748/ejse.23395","url":null,"abstract":"Structure's damping force during an earthquake is very different from what was anticipated during design. This adds uncertainty to the process of designing structures exposed to seismic loads which may be a major cause of significant variation in the seismic response reliability of these structures. This work is focused on the investigation of the structural damping uncertainties effect on the structure’s response spectra through the assessment of uncertainties in the damping reduction factors (DRF) derived from the acceleration, velocity and displacement spectra. An Artificial Neural Networks (ANN) was also developed for the stochastic DRF calculation. The Monte Carlo method, one of the methods of computational algorithms that rely on repeated random sampling to obtain numerical results, is used for the estimation of the stochastic DRF. The obtained results indicates that the difference between the deterministic and the stochastic DRF are around of 21 % for displacement and velocity and 28.7 % for acceleration spectra. As a consequence, the DRF derived from the acceleration spectra is more sensible to the uncertainties inherent on damping than the DRF obtained from displacement and velocity. Therefore, it is important to take this conclusion into account when using these factors previously. The ANN constitutes a sample and efficiency method to predict the stochastic DRF since the error obtained is always less than 6 %. Practice oriented results are searched for, to be incorporated in future seismic standards.","PeriodicalId":52513,"journal":{"name":"Electronic Journal of Structural Engineering","volume":"174 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136185865","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}
Statistics of human losses and financial casualties induced progressive collapse, as one of the new and modern concepts in the field of civil engineering, have doubled the importance of having knowledge about this phenomenon and strategies to reduce its effect. Progressive collapse starts with a local failure with loss of local load-carrying capacity of a small portion of the structure and spreads throughout the structure from element to element. These consecutive failures may cause the collapse of either the entire structure or a major part of it. This paper studies the effect of adding a bracing system to the steel moment frames designed for seismic loads through a nonlinear dynamic method according to GSA-2003 and UFC-4-023-03 criteria. The study was conducted using computational simulation of building models with two different elevations of three and six floors located in a moderate seismicity region. The simulation results showed higher resistance against the progressive collapse of the structure in the braced steel moment frames and less sensitivity to the removal of the column in the braced spans in comparison to the spans without bracing. The prediction of possible progressive collapse in the UFC-4-023-03 criterion is more conservative than the GSA-2003 criterion. Although, generally there is no significant difference between the analysis results of these two criteria.
{"title":"Effects of Structural Bracing on the Progressive Collapse Occurrence","authors":"Emad Raminfar, Ardavan Izadi","doi":"10.56748/ejse.23448","DOIUrl":"https://doi.org/10.56748/ejse.23448","url":null,"abstract":"Statistics of human losses and financial casualties induced progressive collapse, as one of the new and modern concepts in the field of civil engineering, have doubled the importance of having knowledge about this phenomenon and strategies to reduce its effect. Progressive collapse starts with a local failure with loss of local load-carrying capacity of a small portion of the structure and spreads throughout the structure from element to element. These consecutive failures may cause the collapse of either the entire structure or a major part of it. This paper studies the effect of adding a bracing system to the steel moment frames designed for seismic loads through a nonlinear dynamic method according to GSA-2003 and UFC-4-023-03 criteria. The study was conducted using computational simulation of building models with two different elevations of three and six floors located in a moderate seismicity region. The simulation results showed higher resistance against the progressive collapse of the structure in the braced steel moment frames and less sensitivity to the removal of the column in the braced spans in comparison to the spans without bracing. The prediction of possible progressive collapse in the UFC-4-023-03 criterion is more conservative than the GSA-2003 criterion. Although, generally there is no significant difference between the analysis results of these two criteria.","PeriodicalId":52513,"journal":{"name":"Electronic Journal of Structural Engineering","volume":" ","pages":""},"PeriodicalIF":0.6,"publicationDate":"2023-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45660042","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This study investigates the effect of spans length, reinforcement ratio and continuity of flexural reinforcement on the progressive collapse performance of double span beams over failed columns. The investigations focus on initial flexural resisting mechanism to prevent the progressive collapse. Detailed nonlinear finite element simulation of double span beam-column sub-assemblages subjected to residual gravity loads that initially carried by the failed column is adopted for the investigations. Nonlinear static pushover analysis is conducted in which capacity curves are derived and compared with demanded capacities. The effect of spans length, reinforcement ratio and number of continuous bottom flexural reinforcement on progressive collapse are considered in the investigations. Analysis results show that the strength to resist progressive collapse has decreased by 25.4 % and the ductility increased by 103 % following the increasing in span length from 5 m to 7 m. On the other hand, increasing reinforcement ratio of top flexural reinforcement from 0.447 to 1.089 leads to 26.27 % increasing in strength accompanied with a decrease in ductility equal to 16.42 %. In addition, extending all bottom bars rather than the minimum specified two bars resulted in 12 % increasing in strength and 40.28 % decreasing in ductility.
{"title":"Parameters Affect Flexural Mechanism to Prevent Progressive Collapse of RC Buildings","authors":"Z. Najem, Thaer Alrudaini","doi":"10.56748/ejse.234403","DOIUrl":"https://doi.org/10.56748/ejse.234403","url":null,"abstract":"This study investigates the effect of spans length, reinforcement ratio and continuity of flexural reinforcement on the progressive collapse performance of double span beams over failed columns. The investigations focus on initial flexural resisting mechanism to prevent the progressive collapse. Detailed nonlinear finite element simulation of double span beam-column sub-assemblages subjected to residual gravity loads that initially carried by the failed column is adopted for the investigations. Nonlinear static pushover analysis is conducted in which capacity curves are derived and compared with demanded capacities. The effect of spans length, reinforcement ratio and number of continuous bottom flexural reinforcement on progressive collapse are considered in the investigations. Analysis results show that the strength to resist progressive collapse has decreased by 25.4 % and the ductility increased by 103 % following the increasing in span length from 5 m to 7 m. On the other hand, increasing reinforcement ratio of top flexural reinforcement from 0.447 to 1.089 leads to 26.27 % increasing in strength accompanied with a decrease in ductility equal to 16.42 %. In addition, extending all bottom bars rather than the minimum specified two bars resulted in 12 % increasing in strength and 40.28 % decreasing in ductility.","PeriodicalId":52513,"journal":{"name":"Electronic Journal of Structural Engineering","volume":" ","pages":""},"PeriodicalIF":0.6,"publicationDate":"2023-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43533409","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}
In order to analyze the interaction between the operating subway tunnel and the utility tunnel under construction during the utility tunnel under-passing the subway tunnel, an operating tunnel-stratum-utility shield tunnel coupled dynamic calculation model is established taking the utility tunnel under construction under-passing the Guangzhou-Foshan line subway project as an example. And the interaction between the existing tunnel and utility tunnel was studied. The results show that the amplitude change of the vertical displacement, acceleration and additional vertical stress are most influenced by the under-passing shield tunnel when the train operating on one line, and the max changes are 0.01 mm, 0.03m/s2 and 1.5kPa, respectively. The vertical displacement and acceleration response generated by the train operation during the excavation of the new tunnel can be neglected, but the vertical additional stress will have the max change of 2.1kPa. The closer the distance between the train load to the new and old tunnel structures are, the greater the displacement, acceleration and additional stresses of the new and old tunnel structures are when the trains are running in different lines. Structural safety calculations show that the old and new tunnel structures are safe during the utility shield tunnel under-passing. The study can provide useful reference for the construction and operation of similar tunnels.
{"title":"Dynamic response analysis of the process of the utility shield tunnel under-passing the operating subway tunnel","authors":"Jingyao Sun, Xingkai Pei, Cheng Yang, Binzhong Zhu","doi":"10.56748/ejse.234433","DOIUrl":"https://doi.org/10.56748/ejse.234433","url":null,"abstract":"In order to analyze the interaction between the operating subway tunnel and the utility tunnel under construction during the utility tunnel under-passing the subway tunnel, an operating tunnel-stratum-utility shield tunnel coupled dynamic calculation model is established taking the utility tunnel under construction under-passing the Guangzhou-Foshan line subway project as an example. And the interaction between the existing tunnel and utility tunnel was studied. The results show that the amplitude change of the vertical displacement, acceleration and additional vertical stress are most influenced by the under-passing shield tunnel when the train operating on one line, and the max changes are 0.01 mm, 0.03m/s2 and 1.5kPa, respectively. The vertical displacement and acceleration response generated by the train operation during the excavation of the new tunnel can be neglected, but the vertical additional stress will have the max change of 2.1kPa. The closer the distance between the train load to the new and old tunnel structures are, the greater the displacement, acceleration and additional stresses of the new and old tunnel structures are when the trains are running in different lines. Structural safety calculations show that the old and new tunnel structures are safe during the utility shield tunnel under-passing. The study can provide useful reference for the construction and operation of similar tunnels.","PeriodicalId":52513,"journal":{"name":"Electronic Journal of Structural Engineering","volume":" ","pages":""},"PeriodicalIF":0.6,"publicationDate":"2023-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47939694","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This work is based on Winkler’s theory to analyze laterally loaded single piles using the finite element method. Soil nonlinearity is taken into account via nonlinear springs “p-y” curves. Exact element displacement shape functions and stiffness matrix are used for the element in the case of linear Winkler’s modulus of subgrade reaction. In the nonlinear stage, an averaging technique for the element secant Winkler modulus is used to calculate the shape functions and stiffness matrix. An iterative technique is used to take into account the non-linearity of the soil. Few elements are required to simulate the pile efficiently. Unlike other analytical methods, the current method can be used to analyze piles with any load-transfer curves with arbitrary variation with depth.
{"title":"Nonlinear finite element Analysis of laterally loaded piles in Layered Soils","authors":"Haitham Saeed, Huda Saad Abed","doi":"10.56748/ejse.234003","DOIUrl":"https://doi.org/10.56748/ejse.234003","url":null,"abstract":"This work is based on Winkler’s theory to analyze laterally loaded single piles using the finite element method. Soil nonlinearity is taken into account via nonlinear springs “p-y” curves. Exact element displacement shape functions and stiffness matrix are used for the element in the case of linear Winkler’s modulus of subgrade reaction. In the nonlinear stage, an averaging technique for the element secant Winkler modulus is used to calculate the shape functions and stiffness matrix. An iterative technique is used to take into account the non-linearity of the soil. Few elements are required to simulate the pile efficiently. Unlike other analytical methods, the current method can be used to analyze piles with any load-transfer curves with arbitrary variation with depth.","PeriodicalId":52513,"journal":{"name":"Electronic Journal of Structural Engineering","volume":" ","pages":""},"PeriodicalIF":0.6,"publicationDate":"2023-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47486450","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}
The impact factor (IF) assessment of a four-span non-prismatic continuous and an equivalent integral railway bridge under the action of high-speed moving train loads is conducted in this study. Critical analysis of the full-scale three-dimensional finite element (FE) bridge models is done to investigate the differences in the IFs of all the spans of the two-track railway bridge under various loading conditions. A simplified approach is proposed to identify the dynamic IF values. The results show that for a continuous bridge, with the increase in the load on the bridge, IF coefficients reduce from 0.195 to 0.102. However, for the integral bridge, and considered loading conditions, almost similar IF coefficients (0.100) are obtained. For the intermediate spans, the resonance phenomenon for the integral bridge is achieved at lower speeds compared to the equivalent continuous bridge.
{"title":"Study of dynamic impact factors of two-track continuous and integral railway bridge subjected to high-speed loads","authors":"Anand M. Gharad, Ranjan S. Sonparote","doi":"10.56748/ejse.234203","DOIUrl":"https://doi.org/10.56748/ejse.234203","url":null,"abstract":"The impact factor (IF) assessment of a four-span non-prismatic continuous and an equivalent integral railway bridge under the action of high-speed moving train loads is conducted in this study. Critical analysis of the full-scale three-dimensional finite element (FE) bridge models is done to investigate the differences in the IFs of all the spans of the two-track railway bridge under various loading conditions. A simplified approach is proposed to identify the dynamic IF values. The results show that for a continuous bridge, with the increase in the load on the bridge, IF coefficients reduce from 0.195 to 0.102. However, for the integral bridge, and considered loading conditions, almost similar IF coefficients (0.100) are obtained. For the intermediate spans, the resonance phenomenon for the integral bridge is achieved at lower speeds compared to the equivalent continuous bridge.","PeriodicalId":52513,"journal":{"name":"Electronic Journal of Structural Engineering","volume":" ","pages":""},"PeriodicalIF":0.6,"publicationDate":"2023-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45068295","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}
The axial load-carrying capacity for a wide range of short concrete-filled steel tubular (CFST) members having different section profiles is evaluated in the presented work. A numerical study has been carried out through Finite-Element based demonstration and it has been accomplished in the ABAQUS package for relevancy of analytically predicted axial load carrying capacity by unified formula as suggested by Yu M. et al. (2010). To validate the results from the unified formula and the experimentally available literature, finite element-based models for hollow and solid sections of CFST columns with circular, octagonal, and square section profiles have been generated. A total of 31 hollow and 24 solid circular columns, 9 hollow, and 9 solid octagonal columns, and in the last 9 hollows and 38 solid square CFST columns are examined for the persistence of the results. After evaluation of obtained results from the modeling existing results are validated, and it is found that the proposed unified formula predicts satisfactory results when compared with the result of established models. Further, it is concluded that displacement in the direction of applied load is not uniform throughout the length of CFST columns thereby using the ring confinement technique for the region of applied force may be reasonable.
{"title":"Numerical Study on the Various Profile Sections of Concrete Filled Steel Tubular Columns Under Compression","authors":"Vinay Singh, Pramod Kumar Gupta, S. M. Ali Jawaid","doi":"10.56748/ejse.234083","DOIUrl":"https://doi.org/10.56748/ejse.234083","url":null,"abstract":"The axial load-carrying capacity for a wide range of short concrete-filled steel tubular (CFST) members having different section profiles is evaluated in the presented work. A numerical study has been carried out through Finite-Element based demonstration and it has been accomplished in the ABAQUS package for relevancy of analytically predicted axial load carrying capacity by unified formula as suggested by Yu M. et al. (2010). To validate the results from the unified formula and the experimentally available literature, finite element-based models for hollow and solid sections of CFST columns with circular, octagonal, and square section profiles have been generated. A total of 31 hollow and 24 solid circular columns, 9 hollow, and 9 solid octagonal columns, and in the last 9 hollows and 38 solid square CFST columns are examined for the persistence of the results. After evaluation of obtained results from the modeling existing results are validated, and it is found that the proposed unified formula predicts satisfactory results when compared with the result of established models. Further, it is concluded that displacement in the direction of applied load is not uniform throughout the length of CFST columns thereby using the ring confinement technique for the region of applied force may be reasonable.","PeriodicalId":52513,"journal":{"name":"Electronic Journal of Structural Engineering","volume":" ","pages":""},"PeriodicalIF":0.6,"publicationDate":"2023-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48936780","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}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：