1.
Mochammad Qomaruddin; Han Ay Lie; Purwanto; Widayat
Chemical and Microstructural Changes in Reclaimed Asphalt Pavement Aggregates by Pyrolysis Journal Article
In: Arabian Journal for Science and Engineering, 2024.
@article{nokey,
title = {Chemical and Microstructural Changes in Reclaimed Asphalt Pavement Aggregates by Pyrolysis},
author = {Mochammad Qomaruddin and Han Ay Lie and Purwanto and Widayat},
url = {https://link.springer.com/journal/13369},
year = {2024},
date = {2024-01-25},
urldate = {2024-01-25},
journal = { Arabian Journal for Science and Engineering},
abstract = {The utilization of reclaimed asphalt pavement (RAP) aggregates as an alternative for rigid pavements is limited. The main objective of this study is to explore and improve the utilization of RAP aggregates as an alternative material for rigid pavement. Specifically, this study focuses on addressing a significant challenge associated with RAP aggregates, which is their poor bond with cementitious binders. The poor bonding results in low compressive and tensile strengths of concrete or mortar. The poor bonding is mainly due to the presence of a thin oily layer of asphalt residue. A proposed method was carried out to reduce the negative impact on the bond between the aggregate and mortar by exposing the RAP aggregates to the pyrolysis process. The research focused on the analyses of the physical and chemical behavior of the aggregates, using the SEM, EDX, and FTIR approaches, as well as reviewing the mortar in both compressive and flexural tensile strength. The pyrolysis affected the physical and mechanical properties positively and the chemical composition of the RAP showed significant changes. The chemical constituents of asphalt attached to RAP aggregates are hydrocarbons. The thin layer of RAP asphalt is the cause of weak bonding, but this layer was altered by the pyrolysis procedure. As a result, water absorption decreased, which had a positive impact on the hydraulic synergy of cement. It is shown that the pyrolyzing RAP improves the compressive strength and flexural tensile strength through modification of the asphalt residue covering the aggregates.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The utilization of reclaimed asphalt pavement (RAP) aggregates as an alternative for rigid pavements is limited. The main objective of this study is to explore and improve the utilization of RAP aggregates as an alternative material for rigid pavement. Specifically, this study focuses on addressing a significant challenge associated with RAP aggregates, which is their poor bond with cementitious binders. The poor bonding results in low compressive and tensile strengths of concrete or mortar. The poor bonding is mainly due to the presence of a thin oily layer of asphalt residue. A proposed method was carried out to reduce the negative impact on the bond between the aggregate and mortar by exposing the RAP aggregates to the pyrolysis process. The research focused on the analyses of the physical and chemical behavior of the aggregates, using the SEM, EDX, and FTIR approaches, as well as reviewing the mortar in both compressive and flexural tensile strength. The pyrolysis affected the physical and mechanical properties positively and the chemical composition of the RAP showed significant changes. The chemical constituents of asphalt attached to RAP aggregates are hydrocarbons. The thin layer of RAP asphalt is the cause of weak bonding, but this layer was altered by the pyrolysis procedure. As a result, water absorption decreased, which had a positive impact on the hydraulic synergy of cement. It is shown that the pyrolyzing RAP improves the compressive strength and flexural tensile strength through modification of the asphalt residue covering the aggregates.
2.
Laurencius Nugrohoa; Yanuar Haryanto; Hsuan-Teh Hu; and Ay Lie Han; Fu-Pei Hsiao; Chia-Chen Lin; Pu-Wen Weng; Endah Purwaningsih Widiastuti
NSM-CFRP rods with varied embedment depths for strengthening RC T-beams in the negative moment region: Investigation on high cyclic response Journal Article
In: Composite Structures, vol. 331, 2024.
@article{nokey,
title = {NSM-CFRP rods with varied embedment depths for strengthening RC T-beams in the negative moment region: Investigation on high cyclic response},
author = {Laurencius Nugrohoa and Yanuar Haryanto and Hsuan-Teh Hu and and Ay Lie Han and Fu-Pei Hsiao and Chia-Chen Lin and Pu-Wen Weng and Endah Purwaningsih Widiastuti},
url = {https://www.sciencedirect.com/science/article/abs/pii/S0263822324000199},
doi = {10.1016/j.compstruct.2024.117891},
year = {2024},
date = {2024-01-06},
journal = {Composite Structures},
volume = {331},
abstract = {Throughout its service life, structural reinforced concrete (RC) encounters cyclic loads and the load amplitude might always vary, leading to a mixed high and low-cycle failure. This research investigates the high cyclic response of RC T-beams strengthened in the negative moment region using near-surface mounted (NSM) Carbon Fiber Reinforced Polymer (CFRP) rods. The distinctive aspect lies in exploring varied embedment depths, including the introduction of half-embedded configurations as an alternative NSM technique. The study comprehensively analyzes load-carrying capacity, failure modes, energy dissipation, ductility, stiffness degradation, and strain behavior, providing insights into the effects of loading rates on structural response. Through an experimental program comparing fully-embedded (BF-D) and half-embedded (BH-D) CFRP rods with a control beam (BN-D) under high-rate cyclic loading, significant increases in ultimate load capacity (21.23% for BH-D and 30.86% for BF-D) are demonstrated despite debonding occurrences. The findings highlight a trade-off between benefits (enhanced ultimate load capacities, improved energy dissipation, and increased stiffness) and drawbacks (reduced ductility and tendencies toward brittle behavior) under high loading rates. Furthermore, a rate-dependent material formula is developed and validated, predicting the flexural strength of the negative moment region in good agreement with experimental results. Finally, this research contributes practical solutions to RC element strengthening challenges and advances understanding of NSM-CFRP-strengthened beam, emphasizing the impact of loading rates on structural response.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Throughout its service life, structural reinforced concrete (RC) encounters cyclic loads and the load amplitude might always vary, leading to a mixed high and low-cycle failure. This research investigates the high cyclic response of RC T-beams strengthened in the negative moment region using near-surface mounted (NSM) Carbon Fiber Reinforced Polymer (CFRP) rods. The distinctive aspect lies in exploring varied embedment depths, including the introduction of half-embedded configurations as an alternative NSM technique. The study comprehensively analyzes load-carrying capacity, failure modes, energy dissipation, ductility, stiffness degradation, and strain behavior, providing insights into the effects of loading rates on structural response. Through an experimental program comparing fully-embedded (BF-D) and half-embedded (BH-D) CFRP rods with a control beam (BN-D) under high-rate cyclic loading, significant increases in ultimate load capacity (21.23% for BH-D and 30.86% for BF-D) are demonstrated despite debonding occurrences. The findings highlight a trade-off between benefits (enhanced ultimate load capacities, improved energy dissipation, and increased stiffness) and drawbacks (reduced ductility and tendencies toward brittle behavior) under high loading rates. Furthermore, a rate-dependent material formula is developed and validated, predicting the flexural strength of the negative moment region in good agreement with experimental results. Finally, this research contributes practical solutions to RC element strengthening challenges and advances understanding of NSM-CFRP-strengthened beam, emphasizing the impact of loading rates on structural response.
3.
Yanuar Haryanto; Nor Intang Setyo Hermanto; Fu-Pei Hsiao; Hsuan-Teh Hu; Ay Lie Han; Laurencius Nugroho; Fernando Salim
In: The 2nd International Conference on Disaster Mitigation and Management (2nd ICDMM 2023), vol. 464, 2023.
@article{nokey,
title = {Predicting the behavior of RC T-beams strengthened with NSM- CFRP rods in the negative moment region: A finite element approach for low cyclic loading},
author = {Yanuar Haryanto and Nor Intang Setyo Hermanto and Fu-Pei Hsiao and Hsuan-Teh Hu and Ay Lie Han and Laurencius Nugroho and Fernando Salim},
url = {https://www.e3s-conferences.org/articles/e3sconf/abs/2023/101/e3sconf_icdmm2023_06001/e3sconf_icdmm2023_06001.html},
doi = {10.1051/e3sconf/202346406001},
year = {2023},
date = {2023-12-18},
journal = {The 2nd International Conference on Disaster Mitigation and Management (2nd ICDMM 2023)},
volume = {464},
abstract = {In this study, a finite element (FE) model for nonlinear FE analysis was developed to evaluate the performance of reinforced concrete (RC) T-beams, which were strengthened in the negative moment region by near-surface mounted (NSM) carbon fiber reinforced polymer (CFRP) rods under low cyclic loading. Furthermore, the rods' depth of embedment was the research variable. Every component of the beam is considered in the model, including the concrete, steel rebars, CFRP rod, CFRP sheet, adhesive, and stirrups. The nonlinear properties of concrete, steel rebars, and adhesive were taken into account, while that of the CFRP was assumed to be linearly elastic till rupture. In addition, the user-programmable capabilities of ABAQUS were used to define the degradation of each material under low cyclic loading. The developed FE model was then compared to some experimental measurements comprising two specimens strengthened with NSM-CFRP rods and one un-strengthened control specimen. Overall, the predicted FE mid-span deflection responses were in line with the corresponding measured experimentally tested data. Finally, the research findings were summarized.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
In this study, a finite element (FE) model for nonlinear FE analysis was developed to evaluate the performance of reinforced concrete (RC) T-beams, which were strengthened in the negative moment region by near-surface mounted (NSM) carbon fiber reinforced polymer (CFRP) rods under low cyclic loading. Furthermore, the rods' depth of embedment was the research variable. Every component of the beam is considered in the model, including the concrete, steel rebars, CFRP rod, CFRP sheet, adhesive, and stirrups. The nonlinear properties of concrete, steel rebars, and adhesive were taken into account, while that of the CFRP was assumed to be linearly elastic till rupture. In addition, the user-programmable capabilities of ABAQUS were used to define the degradation of each material under low cyclic loading. The developed FE model was then compared to some experimental measurements comprising two specimens strengthened with NSM-CFRP rods and one un-strengthened control specimen. Overall, the predicted FE mid-span deflection responses were in line with the corresponding measured experimentally tested data. Finally, the research findings were summarized.
4.
Laurencius Nugroho; Yanuar Haryanto; Hsuan-Teh Hu; Fu-Pei Hsiao; Ay Lie Han; Arnie Widyaningrum; Hari Prasetijo
Flexural capacity of negative moment region NSM-CFRP strengthened RC T-beam under high loading rate: an analytical prediction Journal Article
In: The 2nd International Conference on Disaster Mitigation and Management (2nd ICDMM 2023), vol. 464, 2023.
@article{nokey,
title = {Flexural capacity of negative moment region NSM-CFRP strengthened RC T-beam under high loading rate: an analytical prediction},
author = {Laurencius Nugroho and Yanuar Haryanto and Hsuan-Teh Hu and Fu-Pei Hsiao and Ay Lie Han and Arnie Widyaningrum and Hari Prasetijo},
url = {https://www.e3s-conferences.org/articles/e3sconf/abs/2023/101/e3sconf_icdmm2023_06004/e3sconf_icdmm2023_06004.html},
doi = {10.1051/e3sconf/202346406004},
year = {2023},
date = {2023-12-18},
journal = {The 2nd International Conference on Disaster Mitigation and Management (2nd ICDMM 2023)},
volume = {464},
abstract = {In the design phase of strengthening a reinforced concrete (RC) beam, it is necessary to determine its capacity. Response-2000 software offers efficient analysis for determining the capacity of a beam, including its flexural capacity. The aim of this study is to assess the predictive accuracy of Response-2000 software in determining the flexural capacity of the negative moment region of NSM-FRP strengthened RC T-beams under high loading rates. The validation of the static material model was initially conducted and then several combinations of established empirical formulations were utilized to express the corresponding dynamic properties of relevant materials. The findings of the study suggest that the compressive and tensile strength of concrete have a significant impact on the flexural capacity of the strengthened beams. Furthermore, empirical evidence supports the idea that Response-2000 possesses the capability to effectively predict the flexural capacity, utilizing a rate-dependent material approach.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
In the design phase of strengthening a reinforced concrete (RC) beam, it is necessary to determine its capacity. Response-2000 software offers efficient analysis for determining the capacity of a beam, including its flexural capacity. The aim of this study is to assess the predictive accuracy of Response-2000 software in determining the flexural capacity of the negative moment region of NSM-FRP strengthened RC T-beams under high loading rates. The validation of the static material model was initially conducted and then several combinations of established empirical formulations were utilized to express the corresponding dynamic properties of relevant materials. The findings of the study suggest that the compressive and tensile strength of concrete have a significant impact on the flexural capacity of the strengthened beams. Furthermore, empirical evidence supports the idea that Response-2000 possesses the capability to effectively predict the flexural capacity, utilizing a rate-dependent material approach.
5.
Purwanto; AyLie Han; B H W Hadikusomo
The influence of reverse loading sequence on the behaviour of beam-column joints Journal Article
In: IOP Conf. Series: Earth and Environmental Science, 2023.
@article{nokey,
title = {The influence of reverse loading sequence on the behaviour of beam-column joints},
author = {Purwanto and AyLie Han and B H W Hadikusomo},
url = {https://iopscience.iop.org/article/10.1088/1755-1315/1244/1/012006},
doi = {10.1088/1755-1315/1244/1/012006},
year = {2023},
date = {2023-10-07},
journal = {IOP Conf. Series: Earth and Environmental Science},
abstract = {The formation of plastic joints in the reinforced beam-to-column joint is influenced by a number of factors. The behaviour and location of this joint is of major importance since it defines the overall performance of the rigid framework when subjected to loading. Mandated by the majority of codes and standards, the strong-column weak-beam philosophy is used and recognized by the formation of this joint in the beam. This study looked into the effect of reverse loading to the behaviour of plastic joints as compared to a monotonic loading protocol. The study analysed the load-deformation behaviour and ultimate load carrying capacity while additional information is collected through visual observation on the failure and cracking pattern. The study concluded that the reverse loading negatively influenced the load carrying capacity, but negligibly affected the overall behaviour of the joint.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The formation of plastic joints in the reinforced beam-to-column joint is influenced by a number of factors. The behaviour and location of this joint is of major importance since it defines the overall performance of the rigid framework when subjected to loading. Mandated by the majority of codes and standards, the strong-column weak-beam philosophy is used and recognized by the formation of this joint in the beam. This study looked into the effect of reverse loading to the behaviour of plastic joints as compared to a monotonic loading protocol. The study analysed the load-deformation behaviour and ultimate load carrying capacity while additional information is collected through visual observation on the failure and cracking pattern. The study concluded that the reverse loading negatively influenced the load carrying capacity, but negligibly affected the overall behaviour of the joint.
6.
Bobby Rio Indriyantho; Aylie Han; Purwanto Purwanto; Nuroji Nuroji; Banu Ardi Hidayat; Buntara Sthenly Gan; Chairul Umam
The Strain Energy Dissipation Behavior of Concrete Tension by Composite Action Journal Article
In: International Journal on Engineering Application (IREA), vol. 11, no. 4, 2023.
@article{nokey,
title = {The Strain Energy Dissipation Behavior of Concrete Tension by Composite Action},
author = {Bobby Rio Indriyantho and Aylie Han and Purwanto Purwanto and Nuroji Nuroji and Banu Ardi Hidayat and Buntara Sthenly Gan and Chairul Umam},
doi = {10.15866/irea.v11i4.23767},
year = {2023},
date = {2023-07-21},
journal = {International Journal on Engineering Application (IREA)},
volume = {11},
number = {4},
abstract = {The concrete tensile deformation energy dissipation is of major interest for reinforced concrete uncracked section design. Extensive research, numerical and experimental, is dedicated on the concrete tension stiffening and its cracking behavior, but limited studies center on the deformation energy dissipation. A steel bar embedded in a cylindrical concrete specimen has been subjected to an axial tensile load, and the load-displacement responses recorded. A variation in concrete compression strength ranging from 32 MPa to 47 MPa has been observed. The focus of this study has been to analyze and formulate the deformation energy dissipation behavior as a function of concrete compression strength and reinforcement ratio. The experimental data have showed that the relationship followed a nonlinear ascending path with a bifurcation point, after which the curve’s gradient has gradually declined. A 3D finite element model has been constructed and validated to the experimental data. The model has been developed to generate the influence of a broad range of reinforcement ratios. An equation for predicting the tensile deformation energy dissipation has been proposed based on experimental and numerical data. The equation is valid for reinforcement ratios ranging from 0.001 to 0.1 and a compression strength of 47 MPa. The equation can be utilized for section optimization purposes. },
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The concrete tensile deformation energy dissipation is of major interest for reinforced concrete uncracked section design. Extensive research, numerical and experimental, is dedicated on the concrete tension stiffening and its cracking behavior, but limited studies center on the deformation energy dissipation. A steel bar embedded in a cylindrical concrete specimen has been subjected to an axial tensile load, and the load-displacement responses recorded. A variation in concrete compression strength ranging from 32 MPa to 47 MPa has been observed. The focus of this study has been to analyze and formulate the deformation energy dissipation behavior as a function of concrete compression strength and reinforcement ratio. The experimental data have showed that the relationship followed a nonlinear ascending path with a bifurcation point, after which the curve’s gradient has gradually declined. A 3D finite element model has been constructed and validated to the experimental data. The model has been developed to generate the influence of a broad range of reinforcement ratios. An equation for predicting the tensile deformation energy dissipation has been proposed based on experimental and numerical data. The equation is valid for reinforcement ratios ranging from 0.001 to 0.1 and a compression strength of 47 MPa. The equation can be utilized for section optimization purposes.
7.
Bagus Hario Setiadji; M. Agung Wibowo; H.M. Jonkers; M. Ottele; Mochammad Qomaruddin; Felix Hariyanto Sugianto; Han Ay Lie
Pyrolysis of Reclaimed Asphalt Aggregates in Mortar Journal Article
In: 2023, ISSN: 2086-9614.
@article{nokey,
title = { Pyrolysis of Reclaimed Asphalt Aggregates in Mortar},
author = {Bagus Hario Setiadji and M. Agung Wibowo and H.M. Jonkers and M. Ottele and Mochammad Qomaruddin and Felix Hariyanto Sugianto and Han Ay Lie
},
url = {https://repository.tudelft.nl/islandora/object/uuid%3Aa9d1b41c-626b-4e64-bcab-41627a2f82e1},
doi = {10.14716/ijtech.v13i4.5621},
issn = {2086-9614},
year = {2023},
date = {2023-07-01},
abstract = {Asphalt pavement consists of aggregates resulting in a waste material at end of its life. The aggregates can be reused as basic material for asphalt or cementitious binding agents. In both scenarios, the recycled aggregates should provide a good bond with the binder to achieve strength. This study focuses on reusing recycled asphalt aggregates (RAA) in mortar. The major weakness of RAA is the thin oily film originating from the asphalt residue, weakening the bond with cement. The pyrolysis method is accessed in an attempt to overcome this weakness. Three scenarios were investigated; the use of virgin aggregates (VA), RAA, and pyrolysis recycled asphalt aggregate (PRAA) as constituent in mortar. All variables were set a constant except for the aggregate type, the VA mortar function as controlling element. This research is methodologically based on experimental data conducted in the laboratory, while aggregate samples were taken from the field. To analyze the influence of pyrolysis to the aggregate-to-cement bond behaviour, qualitative and quantitative data were collected. The quantitative data were the mechanical properties, the mortar tensile, and compression strength. The qualitative data were obtained from scanning electron microscope readings to visually observe the aggregate surface roughness and voids, including the aggregates cross-section and pre-existing micro-cracks in the aggregate-to-cement interface. Supporting data were the aggregates‘ abrasion rate and absorption. The RAA resulted in a significant mortar strength decrease. This conclusion was supported by the findings of pre-existing cracks in the interfacial transition zone. The pyrolysis method improved the compression strength but negligibly affected the tensile behavior. The compression and tensile strength increased as a function of time for both RAA and PRAA, and a strength convergence was reached at 28 days. The PRAA is considered an option for reuse in mortar, supporting nature conservation.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Asphalt pavement consists of aggregates resulting in a waste material at end of its life. The aggregates can be reused as basic material for asphalt or cementitious binding agents. In both scenarios, the recycled aggregates should provide a good bond with the binder to achieve strength. This study focuses on reusing recycled asphalt aggregates (RAA) in mortar. The major weakness of RAA is the thin oily film originating from the asphalt residue, weakening the bond with cement. The pyrolysis method is accessed in an attempt to overcome this weakness. Three scenarios were investigated; the use of virgin aggregates (VA), RAA, and pyrolysis recycled asphalt aggregate (PRAA) as constituent in mortar. All variables were set a constant except for the aggregate type, the VA mortar function as controlling element. This research is methodologically based on experimental data conducted in the laboratory, while aggregate samples were taken from the field. To analyze the influence of pyrolysis to the aggregate-to-cement bond behaviour, qualitative and quantitative data were collected. The quantitative data were the mechanical properties, the mortar tensile, and compression strength. The qualitative data were obtained from scanning electron microscope readings to visually observe the aggregate surface roughness and voids, including the aggregates cross-section and pre-existing micro-cracks in the aggregate-to-cement interface. Supporting data were the aggregates‘ abrasion rate and absorption. The RAA resulted in a significant mortar strength decrease. This conclusion was supported by the findings of pre-existing cracks in the interfacial transition zone. The pyrolysis method improved the compression strength but negligibly affected the tensile behavior. The compression and tensile strength increased as a function of time for both RAA and PRAA, and a strength convergence was reached at 28 days. The PRAA is considered an option for reuse in mortar, supporting nature conservation.
8.
Yanuar Haryanto; Ay Lie Han; Hsuan-Teh Hu; Fu-Pei Hsiao; Buntara Sthenly Gan; Laurencius Nugroho; Chia-Chen Lin
In: Proceedings of the Thirty-third (2023) International Ocean and Polar Engineering Conference, 2023, ISSN: 1098-6189.
@article{nokey,
title = {Impact of Non-Reversed Low Cyclic Loading on the Seismic Response of RC T-Beams Strengthened in the Hogging Zone Using NSM-CFRP Rods with Different Embedment Depth},
author = {Yanuar Haryanto and Ay Lie Han and Hsuan-Teh Hu and Fu-Pei Hsiao and Buntara Sthenly Gan and Laurencius Nugroho and Chia-Chen Lin},
url = {https://onepetro.org/ISOPEIOPEC/proceedings-abstract/ISOPE23/All-ISOPE23/ISOPE-I-23-457/524355?redirectedFrom=PDF},
issn = {1098-6189},
year = {2023},
date = {2023-06-19},
journal = {Proceedings of the Thirty-third (2023) International Ocean and Polar Engineering Conference},
abstract = {It is crucial to preserve the serviceability of offshore structures due to the rise in their numbers. These structures include offshore airports, fortifications, offshore wind power, island reefs, sea light-houses, radar stations, as well as civil and military terminals. Therefore, the initial goal of this study is to present an exploratory campaign on the flexural failure behavior of reinforced concrete (RC) T-beams strengthened in the hogging zone with the near-surface mounted (NSM) technique utilizing carbon fiber-reinforced polymer (CFRP) rods under non-reversed cyclic loading, and second, to determine the impact of the rods’ depth of embedment on the specimens’ overall seismic properties. Additionally, two series of geometrically similar RC T-beams consisting of two strengthened specimens having CFRP rods embedded to various depths as well as an un-strengthened specimen were experimentally tested. The results show that the presence of strengthening materials in the hogging zone influences the flexural failure of the RC T-beams, which experience non-reversed low cyclic loading. In particular, the hysteretic behavior, stiffness deterioration, ductility, and failure modes, as well as the beams’ energy dissipation capacity resulting from the embedment depth of the CFRP rods, were evaluated specifically and in-depth.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
It is crucial to preserve the serviceability of offshore structures due to the rise in their numbers. These structures include offshore airports, fortifications, offshore wind power, island reefs, sea light-houses, radar stations, as well as civil and military terminals. Therefore, the initial goal of this study is to present an exploratory campaign on the flexural failure behavior of reinforced concrete (RC) T-beams strengthened in the hogging zone with the near-surface mounted (NSM) technique utilizing carbon fiber-reinforced polymer (CFRP) rods under non-reversed cyclic loading, and second, to determine the impact of the rods’ depth of embedment on the specimens’ overall seismic properties. Additionally, two series of geometrically similar RC T-beams consisting of two strengthened specimens having CFRP rods embedded to various depths as well as an un-strengthened specimen were experimentally tested. The results show that the presence of strengthening materials in the hogging zone influences the flexural failure of the RC T-beams, which experience non-reversed low cyclic loading. In particular, the hysteretic behavior, stiffness deterioration, ductility, and failure modes, as well as the beams’ energy dissipation capacity resulting from the embedment depth of the CFRP rods, were evaluated specifically and in-depth.
9.
Purwanto Purwanto; Januarti Jaya Ekaputri; Nuroji Nuroji; Bobby Rio Indriyantho; Buntara Sthenly Gan; Ay Lie Han
Geopolymer Haunch Beam‒Column Connection Behavior Journal Article
In: Arabian Journal for Science and Engineering, 2023.
@article{nokey,
title = {Geopolymer Haunch Beam‒Column Connection Behavior},
author = {Purwanto Purwanto and Januarti Jaya Ekaputri and Nuroji Nuroji and Bobby Rio Indriyantho and Buntara Sthenly Gan and Ay Lie Han},
url = {https://link.springer.com/article/10.1007/s13369-023-07921-7},
doi = {10.1007/s13369-023-07921-7},
year = {2023},
date = {2023-05-27},
urldate = {2023-05-27},
journal = {Arabian Journal for Science and Engineering},
abstract = {A haunch system improves the performance of a beam-to-column structure, in combination with a geopolymer haunch, the green-concrete concept is supported by reducing the Portland cement use. The energy dissipation, load‒deformation behavior, failure mode, residual deformation, and plastic hinge formation under a loading‒unloading scheme were studied based on experimental full-scale specimens. The responses of the loading‒unloading protocol were compared to the monotonic loading results. A geopolymer and conventional concrete haunch having similar compressive strengths were analyzed. It was shown that the geopolymer haunch performed excellently and that a concrete haunch remarkably improves the performance of a structure regardless of the haunch material. The geopolymer haunch enhanced the load level at first cracking for 10%, and the formation of plastic hinges 0.7% and 4.5% for the monotonic and loading–unloading, respectively, but slightly reduced the ultimate load by 1%. The loading‒unloading protocol had a negative impact of 3% to 7% on the overall performance, the reduction was lower for the geopolymer haunch underlining the superiority of this material. The loading–unloading scheme resulted in a monotonic strength degradation and deviation in failure mode. A finite element model was constructed to generate and analyze the relation of the haunch’s concrete strength to the load‒deformation response. It was found that the haunch’s compressive strength had no influence on the behavior of the beam-to-column joint, even for a haunch with a compressive strength as low as 25 MPa. },
keywords = {},
pubstate = {published},
tppubtype = {article}
}
A haunch system improves the performance of a beam-to-column structure, in combination with a geopolymer haunch, the green-concrete concept is supported by reducing the Portland cement use. The energy dissipation, load‒deformation behavior, failure mode, residual deformation, and plastic hinge formation under a loading‒unloading scheme were studied based on experimental full-scale specimens. The responses of the loading‒unloading protocol were compared to the monotonic loading results. A geopolymer and conventional concrete haunch having similar compressive strengths were analyzed. It was shown that the geopolymer haunch performed excellently and that a concrete haunch remarkably improves the performance of a structure regardless of the haunch material. The geopolymer haunch enhanced the load level at first cracking for 10%, and the formation of plastic hinges 0.7% and 4.5% for the monotonic and loading–unloading, respectively, but slightly reduced the ultimate load by 1%. The loading‒unloading protocol had a negative impact of 3% to 7% on the overall performance, the reduction was lower for the geopolymer haunch underlining the superiority of this material. The loading–unloading scheme resulted in a monotonic strength degradation and deviation in failure mode. A finite element model was constructed to generate and analyze the relation of the haunch’s concrete strength to the load‒deformation response. It was found that the haunch’s compressive strength had no influence on the behavior of the beam-to-column joint, even for a haunch with a compressive strength as low as 25 MPa.
10.
Laurencius Nugroho; Fu-Pei Hsiao; Hsuan-Teh Hu; Ay Lie Han; Yanuar Haryanto; Gathot Heri Sudibyo; Banu Ardi Hidayat
Residual strength of normal concrete reinforced with aluminum fiber at elevated temperatures Journal Article
In: THE 3RD INTERNATIONAL CONFERENCE ON ENGINEERING, TECHNOLOGY AND INNOVATIVE RESEARCHES, vol. 2482, iss. 1, 2023.
@article{nokey,
title = {Residual strength of normal concrete reinforced with aluminum fiber at elevated temperatures},
author = {Laurencius Nugroho and Fu-Pei Hsiao and Hsuan-Teh Hu and Ay Lie Han and Yanuar Haryanto and Gathot Heri Sudibyo and Banu Ardi Hidayat},
url = {https://pubs.aip.org/aip/acp/article/2482/1/050004/2867340/Residual-strength-of-normal-concrete-reinforced},
doi = {10.1063/5.0110869},
year = {2023},
date = {2023-02-21},
urldate = {2023-02-21},
journal = {THE 3RD INTERNATIONAL CONFERENCE ON ENGINEERING, TECHNOLOGY AND INNOVATIVE RESEARCHES},
volume = {2482},
issue = {1},
abstract = {Civil construction faces an immense challenge due to the damages caused by fire during the construction and service phases. Therefore, it is important to study fire being one of the most severe environmental conditions affecting structures in order to mitigate its effects. Moreover, fiber has been generally discovered to be effective as a reinforced material to improve the strength of concretes. This research was conducted to analyze the residual strength of concretes reinforced with aluminum fibers when exposed to high temperatures. This involved the preparation of 25 MPa concrete specimens with the addition of 0.2% fiber contents exposed to 400 °C and 800 °C temperature for 30 minutes after which their compressive and split cylinder strengths were measured. The result showed the fiber increased the compressive strength by 14.37%, 14.90%, and 2.00%, and the split cylinder strength by 47.27%, 44.29%, and 32.09% at 25°C, 400°C, and 800°C respectively in comparison with the normal concrete.},
keywords = {},
pubstate = {published},
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Civil construction faces an immense challenge due to the damages caused by fire during the construction and service phases. Therefore, it is important to study fire being one of the most severe environmental conditions affecting structures in order to mitigate its effects. Moreover, fiber has been generally discovered to be effective as a reinforced material to improve the strength of concretes. This research was conducted to analyze the residual strength of concretes reinforced with aluminum fibers when exposed to high temperatures. This involved the preparation of 25 MPa concrete specimens with the addition of 0.2% fiber contents exposed to 400 °C and 800 °C temperature for 30 minutes after which their compressive and split cylinder strengths were measured. The result showed the fiber increased the compressive strength by 14.37%, 14.90%, and 2.00%, and the split cylinder strength by 47.27%, 44.29%, and 32.09% at 25°C, 400°C, and 800°C respectively in comparison with the normal concrete.