The novelty of this study is on the combined experimental and statistical methodology-based approach, which is showcased to predict and optimise bamboo-mortar bond strength, incorporating the effect of various material factors affecting it. Design of experiments was used to quantify the impact of multiple factors affecting the bond strength. Firstly, different experimental pull-out tests were conducted in the laboratory to determine the effect of various factors such as water-cement ratio, curing days, cement to sand ratio, fly ash content and bamboo treatment on bond strength development. Three failure patterns, namely bamboo failure, bond failure, and failure of mortar, were observed. Secondly, using a two-level full factorial design method, different statistical models were formulated. These models (M1- Untreated, M2 - Both treated and untreated) were developed based on bamboo surface treatment. The effect of single factors and their interactions were quantified on bond strength development. The developed models were validated to predict bond strength based on different factors. It was concluded that the developed statistical models predicted and simulated the experimental behaviour of bond strength with sufficient accuracy.
{"title":"Performance Assessment of Bamboo Bond Strength in Fly Ash Replaced Cement Mortar","authors":"V. Puri, P. Chakrabortty, S. Majumdar","doi":"10.1680/jstbu.21.00121","DOIUrl":"https://doi.org/10.1680/jstbu.21.00121","url":null,"abstract":"The novelty of this study is on the combined experimental and statistical methodology-based approach, which is showcased to predict and optimise bamboo-mortar bond strength, incorporating the effect of various material factors affecting it. Design of experiments was used to quantify the impact of multiple factors affecting the bond strength. Firstly, different experimental pull-out tests were conducted in the laboratory to determine the effect of various factors such as water-cement ratio, curing days, cement to sand ratio, fly ash content and bamboo treatment on bond strength development. Three failure patterns, namely bamboo failure, bond failure, and failure of mortar, were observed. Secondly, using a two-level full factorial design method, different statistical models were formulated. These models (M1- Untreated, M2 - Both treated and untreated) were developed based on bamboo surface treatment. The effect of single factors and their interactions were quantified on bond strength development. The developed models were validated to predict bond strength based on different factors. It was concluded that the developed statistical models predicted and simulated the experimental behaviour of bond strength with sufficient accuracy.","PeriodicalId":54570,"journal":{"name":"Proceedings of the Institution of Civil Engineers-Structures and Buildings","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2022-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80648747","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The effects of corrosion in two serviceability and capacity state on the failure contingency, life cycle cost, and optimum repair time of reinforced concrete beams are evaluated in this study. Gradual corrosion-induced crack width is obtained by employing the cohesive crack model. Flexural capacity deterioration is examined through a simplified 3D finite element model. Considering the crack width and capacity as random variables in the gamma process, the life cycle cost, and optimum repair time are investigated using a renewal process. Analysis of the effective parameters indicates that corrosion rate in the serviceability state and tensile rebar ratio in the capacity state has the most significant effect on the failure probability, life cycle cost, and optimum repair time. As the corrosion rate decreases, the failure probability reduces, and the repair time increases. With an increase in the aspect ratio of the section, failure cost increases, and the optimum repair time declines.
{"title":"Failure contingency assessment of corroded beams based on structural parameters","authors":"Masoumeh Taghipour, M. Dehestani","doi":"10.1680/jstbu.22.00047","DOIUrl":"https://doi.org/10.1680/jstbu.22.00047","url":null,"abstract":"The effects of corrosion in two serviceability and capacity state on the failure contingency, life cycle cost, and optimum repair time of reinforced concrete beams are evaluated in this study. Gradual corrosion-induced crack width is obtained by employing the cohesive crack model. Flexural capacity deterioration is examined through a simplified 3D finite element model. Considering the crack width and capacity as random variables in the gamma process, the life cycle cost, and optimum repair time are investigated using a renewal process. Analysis of the effective parameters indicates that corrosion rate in the serviceability state and tensile rebar ratio in the capacity state has the most significant effect on the failure probability, life cycle cost, and optimum repair time. As the corrosion rate decreases, the failure probability reduces, and the repair time increases. With an increase in the aspect ratio of the section, failure cost increases, and the optimum repair time declines.","PeriodicalId":54570,"journal":{"name":"Proceedings of the Institution of Civil Engineers-Structures and Buildings","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2022-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77870425","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Recently, Basalt Fiber Reinforced Polymer (BFRP) is expected to be a new excellent material for repair and rehabilitation of civil infrastructure due to its benefit of sound mechanical properties, high corrosion resistant, and low cost. However, studies investigating RC beam externally strengthened with BFRP are still limited in the literature. The objective of this study is to determine the effect of BFRP strengthening on flexural performance of RC beam. Four RC beams with rectangular cross section were produced and strengthened using different BFRP reinforcement techniques and tested under four-point bending until failure. The failure mode, crack width, number of cracks, load-deflection response curves, and ductility of overall beam system were recorded and analyzed. Experimental results showed that the stiffness and the ultimate capacity of the strengthened beam were increased 8%-23% and 14%-30%, respectively, over the control beam. To predict load-carrying capacity and deflection of tested specimens, three-dimension finite element (FE) modeling was performed using ABAQUS software to simulate the behavior of the RC beam strengthened with FRP plates. Prediction with the FE model matched well with experimental results in terms of mid-span deflection and load-carrying capacity.
{"title":"Flexural Strengthening of Reinforced Concrete Beam Bonded with Built-in T Type BFRP Plate","authors":"Buntheng Chhorn, Viriyavudh Sim, Sangmoon Lee, WooYoung Jung","doi":"10.1680/jstbu.22.00026","DOIUrl":"https://doi.org/10.1680/jstbu.22.00026","url":null,"abstract":"Recently, Basalt Fiber Reinforced Polymer (BFRP) is expected to be a new excellent material for repair and rehabilitation of civil infrastructure due to its benefit of sound mechanical properties, high corrosion resistant, and low cost. However, studies investigating RC beam externally strengthened with BFRP are still limited in the literature. The objective of this study is to determine the effect of BFRP strengthening on flexural performance of RC beam. Four RC beams with rectangular cross section were produced and strengthened using different BFRP reinforcement techniques and tested under four-point bending until failure. The failure mode, crack width, number of cracks, load-deflection response curves, and ductility of overall beam system were recorded and analyzed. Experimental results showed that the stiffness and the ultimate capacity of the strengthened beam were increased 8%-23% and 14%-30%, respectively, over the control beam. To predict load-carrying capacity and deflection of tested specimens, three-dimension finite element (FE) modeling was performed using ABAQUS software to simulate the behavior of the RC beam strengthened with FRP plates. Prediction with the FE model matched well with experimental results in terms of mid-span deflection and load-carrying capacity.","PeriodicalId":54570,"journal":{"name":"Proceedings of the Institution of Civil Engineers-Structures and Buildings","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2022-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74516432","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
For detection of cracks in rail sections, various experiments using the acoustic emission technique are carried out by earlier researchers. However, the literature suggests that the study on the optimum location of acoustic emission sensors for the detection of cracks in the railway track is rare. It is difficult to detect defects without the optimal placement of the sensor, due to the complex geometry of the rail section as well as the high cost of sensors. Hence an attempt was made toward the optimum placement of a single sensor on the rail section to detect cracks precisely. Pencil lead break, which simulates a crack, was applied in the rail section to initiate such a crack. The obtained signal was analysed using wavelet transformation to establish a relationship with the group velocity to localise the simulated crack. From the investigation, it was found that the optimum placement of the sensor was between 75 mm to 375 mm for a 1.9 m length of rail section in laboratory conditions.
{"title":"Optimal location of acoustic emission sensors for detecting rail damage","authors":"Tamal Kundu, A. Datta, P. Topdar, S. Sengupta","doi":"10.1680/jstbu.21.00074","DOIUrl":"https://doi.org/10.1680/jstbu.21.00074","url":null,"abstract":"For detection of cracks in rail sections, various experiments using the acoustic emission technique are carried out by earlier researchers. However, the literature suggests that the study on the optimum location of acoustic emission sensors for the detection of cracks in the railway track is rare. It is difficult to detect defects without the optimal placement of the sensor, due to the complex geometry of the rail section as well as the high cost of sensors. Hence an attempt was made toward the optimum placement of a single sensor on the rail section to detect cracks precisely. Pencil lead break, which simulates a crack, was applied in the rail section to initiate such a crack. The obtained signal was analysed using wavelet transformation to establish a relationship with the group velocity to localise the simulated crack. From the investigation, it was found that the optimum placement of the sensor was between 75 mm to 375 mm for a 1.9 m length of rail section in laboratory conditions.","PeriodicalId":54570,"journal":{"name":"Proceedings of the Institution of Civil Engineers-Structures and Buildings","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2022-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73321630","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Xue Li, Lian-guang Wang, Yao-sheng Zhang, Ni Zhang
An experimental and numerical study of the hollow reinforced concrete-filled glass-fibre- reinforced-polymer tubular beams was carried out. Based on the bending tests, the working mechanism and failure modes were studied. A finite-element model was established and the validity was assessed by comparing the experimental and numerical results. The main parameters included the wall thickness of fibreglass tube, the reinforcement ratio, the hollow ratio, the concrete strength and the fibre winding angle. The results indicated that the composite beams failed gradually with considerable ductility. The bending capacity increased by about 12% with every 1 mm increment of the fibreglass tube thickness; increased about 40% as the reinforcement ratio increasing from 2.28% to 4.56%; and increased about 6% with every 5 MPa increment of the concrete strength. The bending capacity decreased and then increased as the fibre winding angles ranging from 10° to 90°, and small fibre winding angle was preferable for the flexural member. The hollow ratio of 0.375 is proved to be applicable to obtain lighter member self-weight with minimal strength decrease.
{"title":"Flexural behaviour of hollow reinforced concrete-filled fibreglass tubular beams","authors":"Xue Li, Lian-guang Wang, Yao-sheng Zhang, Ni Zhang","doi":"10.1680/jstbu.21.00128","DOIUrl":"https://doi.org/10.1680/jstbu.21.00128","url":null,"abstract":"An experimental and numerical study of the hollow reinforced concrete-filled glass-fibre- reinforced-polymer tubular beams was carried out. Based on the bending tests, the working mechanism and failure modes were studied. A finite-element model was established and the validity was assessed by comparing the experimental and numerical results. The main parameters included the wall thickness of fibreglass tube, the reinforcement ratio, the hollow ratio, the concrete strength and the fibre winding angle. The results indicated that the composite beams failed gradually with considerable ductility. The bending capacity increased by about 12% with every 1 mm increment of the fibreglass tube thickness; increased about 40% as the reinforcement ratio increasing from 2.28% to 4.56%; and increased about 6% with every 5 MPa increment of the concrete strength. The bending capacity decreased and then increased as the fibre winding angles ranging from 10° to 90°, and small fibre winding angle was preferable for the flexural member. The hollow ratio of 0.375 is proved to be applicable to obtain lighter member self-weight with minimal strength decrease.","PeriodicalId":54570,"journal":{"name":"Proceedings of the Institution of Civil Engineers-Structures and Buildings","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2022-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79117973","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In order to investigate the influence of substructures on the seismic performance of the suspen-dome structure, taking the suspen-dome roof structure of the Lanzhou Olympic Sports Center Complex as the prototype, a method that replaces complex concrete substructures of the prototype structure with steel substructures in shaking table test was proposed and a scale model considering substructures was established. Firstly, the natural frequencies of the test model were compared with the modal analysis results of the prototype structure considering the scale ratio. After that, an integral numerical model considering substructures was established by ABAQUS, the results of modal analysis and dynamic time history analysis were compared with the test results. Finally, two simplified numerical models with boundary conditions of fixed bearings and three-directional hinged bearings were established. The seismic performances of simplified models and the integral model were compared. It is observed that the method of considering complex concrete substructures of the prototype structure in the shaking table test is accurate and effective. Besides, the numerical model and the modeling method are correct. Moreover, the substructure has a significant impact on the seismic performance of the suspen-dome. The substructure should be considered in the analysis and design stages.
{"title":"Influence of considering substructures on seismic performances of suspen-dome structure","authors":"Zetao Zhao, X. Li, Renjie Liu, Suduo Xue, Tifeng Liu, Qinxin Fan, Hui Jing, Majid Dezhkam","doi":"10.1680/jstbu.21.00187","DOIUrl":"https://doi.org/10.1680/jstbu.21.00187","url":null,"abstract":"In order to investigate the influence of substructures on the seismic performance of the suspen-dome structure, taking the suspen-dome roof structure of the Lanzhou Olympic Sports Center Complex as the prototype, a method that replaces complex concrete substructures of the prototype structure with steel substructures in shaking table test was proposed and a scale model considering substructures was established. Firstly, the natural frequencies of the test model were compared with the modal analysis results of the prototype structure considering the scale ratio. After that, an integral numerical model considering substructures was established by ABAQUS, the results of modal analysis and dynamic time history analysis were compared with the test results. Finally, two simplified numerical models with boundary conditions of fixed bearings and three-directional hinged bearings were established. The seismic performances of simplified models and the integral model were compared. It is observed that the method of considering complex concrete substructures of the prototype structure in the shaking table test is accurate and effective. Besides, the numerical model and the modeling method are correct. Moreover, the substructure has a significant impact on the seismic performance of the suspen-dome. The substructure should be considered in the analysis and design stages.","PeriodicalId":54570,"journal":{"name":"Proceedings of the Institution of Civil Engineers-Structures and Buildings","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2022-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80474142","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The seismic performance of a ring-beam connection system that integrates concrete-filled steel tubular columns and reinforced concrete frames was studied. Physical experiments on two fabricated specimens were conducted under monotonic and cyclic loading. The results showed the connection system had a displacement ductility ratio of 4.68 and an energy dissipation coefficient over 2.0. A finite-element model was established and the numerical and experimental results were compared in terms of skeleton curve and stiffness degradation trend. Parametric studies were then performed to evaluate the effects of axial compressive force ratio, concrete strength and reinforcement ratio for the ring-beam joint, and reinforcement ratio for the frame beam, on the seismic performance of the proposed connection system. The results indicated that the increase in the axial compression ratio or strength of the concrete material would improve the initial stiffness and strength of the connection system. However, the effect of the ring-beam joint reinforcement ratio and frame beam reinforcement ratio of the connection system on the seismic performance was negligible.
{"title":"Seismic performance of a ring beam connecting filled-tube columns with concrete frames","authors":"K. Dai, Qianqian Li, Jianze Wang, Zhenhua Huang","doi":"10.1680/jstbu.21.00173","DOIUrl":"https://doi.org/10.1680/jstbu.21.00173","url":null,"abstract":"The seismic performance of a ring-beam connection system that integrates concrete-filled steel tubular columns and reinforced concrete frames was studied. Physical experiments on two fabricated specimens were conducted under monotonic and cyclic loading. The results showed the connection system had a displacement ductility ratio of 4.68 and an energy dissipation coefficient over 2.0. A finite-element model was established and the numerical and experimental results were compared in terms of skeleton curve and stiffness degradation trend. Parametric studies were then performed to evaluate the effects of axial compressive force ratio, concrete strength and reinforcement ratio for the ring-beam joint, and reinforcement ratio for the frame beam, on the seismic performance of the proposed connection system. The results indicated that the increase in the axial compression ratio or strength of the concrete material would improve the initial stiffness and strength of the connection system. However, the effect of the ring-beam joint reinforcement ratio and frame beam reinforcement ratio of the connection system on the seismic performance was negligible.","PeriodicalId":54570,"journal":{"name":"Proceedings of the Institution of Civil Engineers-Structures and Buildings","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2022-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77825166","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Single-column continuous-curved-beam bridges are often used in earthquake-prone areas, but their design characteristics make it difficult to predict structural damage during an earthquake. A large-scale model of a single-column, continuous-curbed-beam overpass that was damaged during the Wenchuan earthquake was created and tested on a shaking table. After the pier suffered seismic damage it was repaired using a polyurethane cement and re-tested. The results of the study revealed that polyurethane cement repair can improve the structural performance of this type of bridge and is a valid new method for the quick repair of earthquake-damaged bridge piers.
{"title":"Earthquake repair of a single-column continuous-beam bridge with polyurethane cement","authors":"Haoyang Zhang, Quansheng Sun, Hongxiang Xia, Dezhang Sun, Yong Huang","doi":"10.1680/jstbu.21.00167","DOIUrl":"https://doi.org/10.1680/jstbu.21.00167","url":null,"abstract":"Single-column continuous-curved-beam bridges are often used in earthquake-prone areas, but their design characteristics make it difficult to predict structural damage during an earthquake. A large-scale model of a single-column, continuous-curbed-beam overpass that was damaged during the Wenchuan earthquake was created and tested on a shaking table. After the pier suffered seismic damage it was repaired using a polyurethane cement and re-tested. The results of the study revealed that polyurethane cement repair can improve the structural performance of this type of bridge and is a valid new method for the quick repair of earthquake-damaged bridge piers.","PeriodicalId":54570,"journal":{"name":"Proceedings of the Institution of Civil Engineers-Structures and Buildings","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2022-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91037903","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Chaofeng Liu, B. Zhou, Qianqian Liu, Cai‐wei Liu, Lingui Wang, Fei Xing
In order to study the effect of high temperatures on the thermomechanical properties of RC beams, fire and mechanical tests were carried out on four fully-dimensioned simply supported beams. A numerical analysis model based on the measured information was developed, and it was validated through experimental tests and theoretical calculations. The effects of fire exposure time, different physical parameters and concrete spalling parameters on the thermodynamic properties were further analyzed. The results show that the measured vibration frequencies appear a fluctuating trend of decay with increasing fire exposure time. The simulated frequency decays as a power function of fire exposure time. The frequency decreases with increasing span-to-height ratio and increases with section width, elasticity modulus of concrete and reinforcement ratio, respectively. Cross-sectional temperature field is most significantly affected by spalling depth, which increases rapidly with its increasing. With the increase in spalling area ratio, the increase in the temperature field gradually becomes smaller. The effect of spalling area ratio was relatively stable after more than 15%. The flexural bearing capacity shows a linear decrease trend with the increase in spalling depth. With the increase in spalling area ratio, it shows a power function of the decreasing trend.
{"title":"Study on thermodynamic properties of RC beams considering elevated temperature and spalling effect","authors":"Chaofeng Liu, B. Zhou, Qianqian Liu, Cai‐wei Liu, Lingui Wang, Fei Xing","doi":"10.1680/jstbu.21.00201","DOIUrl":"https://doi.org/10.1680/jstbu.21.00201","url":null,"abstract":"In order to study the effect of high temperatures on the thermomechanical properties of RC beams, fire and mechanical tests were carried out on four fully-dimensioned simply supported beams. A numerical analysis model based on the measured information was developed, and it was validated through experimental tests and theoretical calculations. The effects of fire exposure time, different physical parameters and concrete spalling parameters on the thermodynamic properties were further analyzed. The results show that the measured vibration frequencies appear a fluctuating trend of decay with increasing fire exposure time. The simulated frequency decays as a power function of fire exposure time. The frequency decreases with increasing span-to-height ratio and increases with section width, elasticity modulus of concrete and reinforcement ratio, respectively. Cross-sectional temperature field is most significantly affected by spalling depth, which increases rapidly with its increasing. With the increase in spalling area ratio, the increase in the temperature field gradually becomes smaller. The effect of spalling area ratio was relatively stable after more than 15%. The flexural bearing capacity shows a linear decrease trend with the increase in spalling depth. With the increase in spalling area ratio, it shows a power function of the decreasing trend.","PeriodicalId":54570,"journal":{"name":"Proceedings of the Institution of Civil Engineers-Structures and Buildings","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2022-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79673008","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Iqrar Hussain, M. Yaqub, M. Mortazavi, Muhammad Adeel Ehsan, Mudasir Hussain
This paper presents numerical and regression modeling of 21 undamaged, fire-damaged, and repaired fire-damaged reinforced circular concrete (RC) columns. The columns were exposed to three different temperatures of 300°C, 500°C, and 900°C and tested for axial residual capacity. It was found that concrete loses its strength after exposure to a temperature of 300°C or above. Fire-damaged columns were then repaired using various composite confinement techniques. Strength was regained when CFRP confinement was applied to fire-damaged columns but it increased the deformation as well and thus reduced the stiffness which is not desirable. To overcome this challenge, steel wire mesh, filled with cement sand mortar and wrapped with CFRP was employed. Further, a numerical model was developed that could precisely predict the residual capacity of these columns. The paper briefly reviewed and summarised the development of numerical techniques, including material properties, geometry, elements, loading, boundary conditions, and contact algorithm for undamaged, fire-damaged, and repaired fire-damaged columns. Moreover, analytical equations were developed using linear, multiple, and quadratic regression modeling. The results obtained using the proposed model and regression equations showed that these models offered a better alternative to the experimental testing for the prediction of the post-fire performance of damaged and repaired RC columns.
{"title":"Analytical and Numerical Study of Fire-Damaged Circular Concrete Columns Repaired Using Composite Confinement Techniques","authors":"Iqrar Hussain, M. Yaqub, M. Mortazavi, Muhammad Adeel Ehsan, Mudasir Hussain","doi":"10.1680/jstbu.21.00017","DOIUrl":"https://doi.org/10.1680/jstbu.21.00017","url":null,"abstract":"This paper presents numerical and regression modeling of 21 undamaged, fire-damaged, and repaired fire-damaged reinforced circular concrete (RC) columns. The columns were exposed to three different temperatures of 300°C, 500°C, and 900°C and tested for axial residual capacity. It was found that concrete loses its strength after exposure to a temperature of 300°C or above. Fire-damaged columns were then repaired using various composite confinement techniques. Strength was regained when CFRP confinement was applied to fire-damaged columns but it increased the deformation as well and thus reduced the stiffness which is not desirable. To overcome this challenge, steel wire mesh, filled with cement sand mortar and wrapped with CFRP was employed. Further, a numerical model was developed that could precisely predict the residual capacity of these columns. The paper briefly reviewed and summarised the development of numerical techniques, including material properties, geometry, elements, loading, boundary conditions, and contact algorithm for undamaged, fire-damaged, and repaired fire-damaged columns. Moreover, analytical equations were developed using linear, multiple, and quadratic regression modeling. The results obtained using the proposed model and regression equations showed that these models offered a better alternative to the experimental testing for the prediction of the post-fire performance of damaged and repaired RC columns.","PeriodicalId":54570,"journal":{"name":"Proceedings of the Institution of Civil Engineers-Structures and Buildings","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2022-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81897578","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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