1.
Hanna Chintya Febriani Gunawan; John Thedy; Bagus Hario Setiadji; Ay Lie Han; Marc Ottele
In: Journal of Building Engineering, vol. 108, 2025.
@article{nokey,
title = {A novel Pareto Front Symbiotic Organism Search (PF-SOS) combined with metaheuristic-optimized machine learning for optimal recycled aggregate concrete mixtures},
author = {Hanna Chintya Febriani Gunawan and John Thedy and Bagus Hario Setiadji and Ay Lie Han and Marc Ottele },
url = {https://www.sciencedirect.com/science/article/abs/pii/S2352710225012288},
doi = {10.1016/j.jobe.2025.112991},
year = {2025},
date = {2025-08-15},
journal = {Journal of Building Engineering},
volume = {108},
abstract = {Recycled Aggregate Concrete (RAC) represents a significant innovation aimed at reducing the carbon footprint in the construction industry. Over the past few decades, numerous investigations and experiments have confirmed the viability of RAC as a construction material when the optimal combination of recycled and natural aggregates is used. This study seeks to further enhance the application of RAC by providing a robust framework for determining the optimal RAC mixture. To achieve this, machine learning is developed to predict the compressive strength of RAC by considering various mixture properties. To improve the accuracy of these predictions, the Symbiotic Organism Search (SOS) metaheuristic algorithm is employed, not only to fine-tune the machine learning hyperparameters but also to select the most suitable model. In this study, the SOS algorithm is tasked with choosing between Artificial Neural Networks (ANN), Support Vector Machines (SVM), or Random Forests (RF), based on predefined upper and lower bounds for their hyperparameters. The resulting machine learning model is then integrated with the novel Pareto Front Symbiotic Organism Search (PF-SOS) to generate a Pareto front of optimal mixtures, with compressive strength and production cost as the objectives. To validate the efficiency of the proposed method, the PF-SOS results are compared with those from other well-known multi-objective optimization algorithms. The findings demonstrate that PF-SOS offers faster convergence and a broader range of mixture options within the same function evaluation limit. },
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Recycled Aggregate Concrete (RAC) represents a significant innovation aimed at reducing the carbon footprint in the construction industry. Over the past few decades, numerous investigations and experiments have confirmed the viability of RAC as a construction material when the optimal combination of recycled and natural aggregates is used. This study seeks to further enhance the application of RAC by providing a robust framework for determining the optimal RAC mixture. To achieve this, machine learning is developed to predict the compressive strength of RAC by considering various mixture properties. To improve the accuracy of these predictions, the Symbiotic Organism Search (SOS) metaheuristic algorithm is employed, not only to fine-tune the machine learning hyperparameters but also to select the most suitable model. In this study, the SOS algorithm is tasked with choosing between Artificial Neural Networks (ANN), Support Vector Machines (SVM), or Random Forests (RF), based on predefined upper and lower bounds for their hyperparameters. The resulting machine learning model is then integrated with the novel Pareto Front Symbiotic Organism Search (PF-SOS) to generate a Pareto front of optimal mixtures, with compressive strength and production cost as the objectives. To validate the efficiency of the proposed method, the PF-SOS results are compared with those from other well-known multi-objective optimization algorithms. The findings demonstrate that PF-SOS offers faster convergence and a broader range of mixture options within the same function evaluation limit.
2.
Bobby Rio Indriyantho; Blinka Hernawan Prasetya; Banu Ardi Hidayat; Herry Puguh Prasetya; Ay Lie Han; Michael Kaliske
Tensile behavior of self-compacting geopolymer concrete considering tension stiffening Author links open overlay panel Journal Article
In: Journal of Building Engineering, vol. 105, 2025.
@article{nokey,
title = {Tensile behavior of self-compacting geopolymer concrete considering tension stiffening Author links open overlay panel},
author = {Bobby Rio Indriyantho and Blinka Hernawan Prasetya and Banu Ardi Hidayat and Herry Puguh Prasetya and Ay Lie Han and Michael Kaliske},
url = {https://www.sciencedirect.com/science/article/abs/pii/S2352710225006394},
doi = {10.1016/j.jobe.2025.112402},
year = {2025},
date = {2025-07-01},
journal = {Journal of Building Engineering},
volume = {105},
abstract = {When it comes to lowering carbon emissions due to the production of cement, geopolymer concrete holds great promise as an environmentally friendly alternative to conventional cement-based concrete. Due to the variation in its material constituents, building codes do not yet mandate any specific norm for its mechanical properties. In the meantime, since reinforced concrete with steel reinforcements has taken up the tensile contribution, the behavior of concrete under tension has little bearing on construction designs. However, it might not be accurate to disregard concrete’s tensile strength for analyses meant to identify structural responses. With reference to the tension stiffening phenomenon of reinforcing steel embedded in a cylindrical self-compacting geopolymer concrete (SCGC) with certain dimensions, the goal of this work is to examine the tensile behavior of SCGC. The behavior of this specimen under tension, including its strength and the relationship between stress and strain, as well as its crack pattern and failure mechanism, is determined via uniaxial tensile testing, considering tension stiffening phenomena. Following normalization, the results are compared to the tensile performance of conventional concrete under identical circumstances and evaluated against the standard building code.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
When it comes to lowering carbon emissions due to the production of cement, geopolymer concrete holds great promise as an environmentally friendly alternative to conventional cement-based concrete. Due to the variation in its material constituents, building codes do not yet mandate any specific norm for its mechanical properties. In the meantime, since reinforced concrete with steel reinforcements has taken up the tensile contribution, the behavior of concrete under tension has little bearing on construction designs. However, it might not be accurate to disregard concrete’s tensile strength for analyses meant to identify structural responses. With reference to the tension stiffening phenomenon of reinforcing steel embedded in a cylindrical self-compacting geopolymer concrete (SCGC) with certain dimensions, the goal of this work is to examine the tensile behavior of SCGC. The behavior of this specimen under tension, including its strength and the relationship between stress and strain, as well as its crack pattern and failure mechanism, is determined via uniaxial tensile testing, considering tension stiffening phenomena. Following normalization, the results are compared to the tensile performance of conventional concrete under identical circumstances and evaluated against the standard building code.
3.
Malik Mushthofa; John Thedy; Mochamad Teguh; Purwanto; Adjie Gemilang Pratama; Ay Lie Han
Artificial Intelligence in Geopolymer Concrete Mix Design: A Comprehensive Review of Techniques and Applications Journal Article
In: Iranian Journal of Science and Technology, Transactions of Civil Engineering , 2025.
@article{nokey,
title = {Artificial Intelligence in Geopolymer Concrete Mix Design: A Comprehensive Review of Techniques and Applications},
author = {Malik Mushthofa and John Thedy and Mochamad Teguh and Purwanto and Adjie Gemilang Pratama and Ay Lie Han },
url = {https://link.springer.com/article/10.1007/s40996-025-01873-8},
year = {2025},
date = {2025-05-13},
journal = { Iranian Journal of Science and Technology, Transactions of Civil Engineering },
abstract = {This systematic review explores the application of Artificial Intelligence (AI) in optimizing the mix design of fly ash-based geopolymer concrete (FABGC). Analyzing studies published between 2014 and 2025, it examines key methodologies, including machine learning models, optimization algorithms, and multi-criteria decision-making approaches. Critical aspects such as data preprocessing, AI model selection, hyperparameter tuning, explainable AI (XAI), and optimization strategies are synthesized to provide a comprehensive perspective on AI-driven FABGC research. The review identifies Deep Residual Networks (ResNet) and Extreme Gradient Boosting (XGB) as the most accurate models for predicting FABGC strength, consistently outperforming others due to their lower error metrics. Backpropagation Neural Networks (BPNN) and Adaptive Neuro-Fuzzy Inference Systems (ANFIS) also demonstrate competitive performance, while Random Forest (RF) and Decision Tree (DT) models excel in computational efficiency with shorter training times. Despite being the most widely implemented, Artificial Neural Networks (ANN) rarely achieve the highest predictive accuracy. Traditional regression methods, though straightforward, lag behind in performance. These findings underscore the need for standardized datasets, enhanced collaboration, and innovative AI-driven approaches to improve FABGC mix design optimization. Addressing these challenges will facilitate more reliable and efficient AI applications in sustainable concrete technology.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
This systematic review explores the application of Artificial Intelligence (AI) in optimizing the mix design of fly ash-based geopolymer concrete (FABGC). Analyzing studies published between 2014 and 2025, it examines key methodologies, including machine learning models, optimization algorithms, and multi-criteria decision-making approaches. Critical aspects such as data preprocessing, AI model selection, hyperparameter tuning, explainable AI (XAI), and optimization strategies are synthesized to provide a comprehensive perspective on AI-driven FABGC research. The review identifies Deep Residual Networks (ResNet) and Extreme Gradient Boosting (XGB) as the most accurate models for predicting FABGC strength, consistently outperforming others due to their lower error metrics. Backpropagation Neural Networks (BPNN) and Adaptive Neuro-Fuzzy Inference Systems (ANFIS) also demonstrate competitive performance, while Random Forest (RF) and Decision Tree (DT) models excel in computational efficiency with shorter training times. Despite being the most widely implemented, Artificial Neural Networks (ANN) rarely achieve the highest predictive accuracy. Traditional regression methods, though straightforward, lag behind in performance. These findings underscore the need for standardized datasets, enhanced collaboration, and innovative AI-driven approaches to improve FABGC mix design optimization. Addressing these challenges will facilitate more reliable and efficient AI applications in sustainable concrete technology.
4.
Dinar Gumilang Jati; Mhd Rony Asshidiqie; Bobby Rio Indriyantho; Viktor Mechtcherine; Buntara Sthenly Gan; Ay Lie Han
Stress–strain behavior of CFRP-bond to steel in tension Journal Article
In: Materials and Structures , vol. 58, no. 123, 2025.
@article{nokey,
title = {Stress–strain behavior of CFRP-bond to steel in tension},
author = {Dinar Gumilang Jati and Mhd Rony Asshidiqie and Bobby Rio Indriyantho and Viktor Mechtcherine and Buntara Sthenly Gan and Ay Lie Han },
url = {https://link.springer.com/article/10.1617/s11527-025-02666-1},
year = {2025},
date = {2025-04-24},
journal = {Materials and Structures },
volume = {58},
number = {123},
abstract = {Carbon fiber reinforced polymer (CFRP) sheets are used to externally reinforce structural elements. Compatibility is of major importance to transfer stresses and strains from the reinforced member to the CFRP through the bond. This bond is a contribution of three layers: the adhesive-to-structure, the adhesive-to-CFRP bond, and the properties of the adhesive-impregnated CFRP. While in modeling, the CFRP is assumed to be fully bonded; test results suggested that this assumption overestimated post-peak responses in particular. Defining accurate CFRP bond behavior is therefore obligatory in modeling. This research aimed to construct accurate stress–strain responses of CFRP bond layers. The study acquired this by investigating the strain-gauge responses at each layer as a function of incremental loading. CFRP sheets with a variation in length ranging from 40 to 120 mm were attached to a 300 mm steel plate subjected to flexural stresses. The CFRP was situated in the tensile zone. The steel plate was favored to ensure the failure mode occurred in the CFRP layer. It was concluded that bond length significantly influenced the transfer mechanism, concluding a minimum effective CFRP length of 100 mm. All stress–strain bond relationships are characterized by bilinear responses, with almost identical adhesive-to-CFRP and impregnated CFRP behavior. The adhesive-to-structural layer had a lower ultimate stress and post-peak response; initial stiffnesses were undifferentiated. An implementation of the obtained stress–strain response into a finite element analysis (FEA) demonstrated the accuracy of the results and the significant deviation when a full bond is assumed through the toughness of the strengthened member.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Carbon fiber reinforced polymer (CFRP) sheets are used to externally reinforce structural elements. Compatibility is of major importance to transfer stresses and strains from the reinforced member to the CFRP through the bond. This bond is a contribution of three layers: the adhesive-to-structure, the adhesive-to-CFRP bond, and the properties of the adhesive-impregnated CFRP. While in modeling, the CFRP is assumed to be fully bonded; test results suggested that this assumption overestimated post-peak responses in particular. Defining accurate CFRP bond behavior is therefore obligatory in modeling. This research aimed to construct accurate stress–strain responses of CFRP bond layers. The study acquired this by investigating the strain-gauge responses at each layer as a function of incremental loading. CFRP sheets with a variation in length ranging from 40 to 120 mm were attached to a 300 mm steel plate subjected to flexural stresses. The CFRP was situated in the tensile zone. The steel plate was favored to ensure the failure mode occurred in the CFRP layer. It was concluded that bond length significantly influenced the transfer mechanism, concluding a minimum effective CFRP length of 100 mm. All stress–strain bond relationships are characterized by bilinear responses, with almost identical adhesive-to-CFRP and impregnated CFRP behavior. The adhesive-to-structural layer had a lower ultimate stress and post-peak response; initial stiffnesses were undifferentiated. An implementation of the obtained stress–strain response into a finite element analysis (FEA) demonstrated the accuracy of the results and the significant deviation when a full bond is assumed through the toughness of the strengthened member.
5.
Yanuar Haryanto; Nanang Gunawan Wariyatno; Fu-Pei Hsiao; Hsuan-Teh Hu; Ay Lie Han; Laurencius Nugroho; Hioe Hartono
RC T-beams with flexural strengthening in the negative moment region under different configurations of NSM CFRP rods Journal Article
In: Engineering Failure Analysis, vol. 173, 2025.
@article{nokey,
title = {RC T-beams with flexural strengthening in the negative moment region under different configurations of NSM CFRP rods},
author = {Yanuar Haryanto and Nanang Gunawan Wariyatno and Fu-Pei Hsiao and Hsuan-Teh Hu and Ay Lie Han and Laurencius Nugroho and Hioe Hartono },
url = {https://www.sciencedirect.com/science/article/abs/pii/S1350630725001992?via%3Dihub},
doi = {10.1016/j.engfailanal.2025.109458},
year = {2025},
date = {2025-02-27},
journal = {Engineering Failure Analysis},
volume = {173},
abstract = {This study employed a near-surface mounted (NSM) technique to enhance the flexural performance of reinforced concrete (RC) T-beams in the negative moment region, using carbon fiber reinforced polymer (CFRP) rods embedded at varying depths. An experimental investigation was conducted, supported by analytical calculations and finite element (FE) simulations, to validate the results. The experiments revealed that beams with half-embedded CFRP rods experienced partial debonding at significant crack locations, a problem potentially mitigated by fully embedded rods. Strengthening with NSM-CFRP rods increased cracking, yield, and ultimate loads by 10–21%, 36–38%, and 30–40%, respectively, compared to control beams, while also enhancing stiffness. However, these methods may have a twofold impact on the specimen by decreasing its ductility and energy absorption capacity. The analytical approach provided accurate and conservative predictions, with a coefficient of variation of 4.5%, while the FE model demonstrated high accuracy, achieving a coefficient of variation of 3.5% when compared to experimental flexural load capacity results.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
This study employed a near-surface mounted (NSM) technique to enhance the flexural performance of reinforced concrete (RC) T-beams in the negative moment region, using carbon fiber reinforced polymer (CFRP) rods embedded at varying depths. An experimental investigation was conducted, supported by analytical calculations and finite element (FE) simulations, to validate the results. The experiments revealed that beams with half-embedded CFRP rods experienced partial debonding at significant crack locations, a problem potentially mitigated by fully embedded rods. Strengthening with NSM-CFRP rods increased cracking, yield, and ultimate loads by 10–21%, 36–38%, and 30–40%, respectively, compared to control beams, while also enhancing stiffness. However, these methods may have a twofold impact on the specimen by decreasing its ductility and energy absorption capacity. The analytical approach provided accurate and conservative predictions, with a coefficient of variation of 4.5%, while the FE model demonstrated high accuracy, achieving a coefficient of variation of 3.5% when compared to experimental flexural load capacity results.
6.
Muhammad Farhan; Han Ay Lie; Purwanto; Bonaventura Harimurti W. Hadikusumo
Mechanical And Physical Behavior Of Self-healing Concrete Using Bacillus Megaterium Bacteria Journal Article
In: International Journal of GEOMATE, vol. 28, no. 125, pp. 83-91, 2025, ISSN: 2186-2982 .
@article{nokey,
title = {Mechanical And Physical Behavior Of Self-healing Concrete Using Bacillus Megaterium Bacteria },
author = {Muhammad Farhan and Han Ay Lie and Purwanto and Bonaventura Harimurti W. Hadikusumo},
url = {https://geomatejournal.com/geomate/article/view/4715/3551},
issn = { 2186-2982 },
year = {2025},
date = {2025-01-17},
journal = {International Journal of GEOMATE},
volume = {28},
number = {125},
pages = {83-91},
abstract = {The Bacillus megaterium bacteria synergy on concrete mechanical and physical properties to enhance durability and strength through self-healing is studied. Two Bacillus megaterium concentration variations, variations of 4% and 8% to water volume, were added to fresh concrete based on the substitution method. NC0 stands for 0% bacteria and functions as a control specimen, while SHC4 and SHC8 represented 4% and 8% bacteria content, respectively. The primary focus was to analyze the compressive strength, density, permeable voids, and water absorption behavior at ages 28 and 56 days. Results indicated that the bacteria significantly improved the mechanical properties of hardened concrete. SHC4 and SHC8 exhibited a compressive strength increase of 8% and 14% at 28 days and 15% and 19% at 56 days compared to NC0. This strength increase resulted from permeable voids and water absorption reduction, as well as an improved aggregate-to-mortar ITZ bond due to the formation of bacteria-produced CaCO3, which filled the voids. Reduction in permeable voids and water absorption were 7% to 17%, while density improvement was up to 10% at 28 days. A higher bacteria content consequently produced a better void-filling mechanism. The SHC8 with 8% Bacillus megaterium was proven more effective than SHC4. The 56-day specimens revealed that a significant concrete performance enhancement resulted from the development of CaCO3 deposits over time. It is interesting for further studies to determine the bacteria effectiveness convergence as a function of hardening time. This research highlights the potential of biological approach methods for developing sustainable and resilient construction materials.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The Bacillus megaterium bacteria synergy on concrete mechanical and physical properties to enhance durability and strength through self-healing is studied. Two Bacillus megaterium concentration variations, variations of 4% and 8% to water volume, were added to fresh concrete based on the substitution method. NC0 stands for 0% bacteria and functions as a control specimen, while SHC4 and SHC8 represented 4% and 8% bacteria content, respectively. The primary focus was to analyze the compressive strength, density, permeable voids, and water absorption behavior at ages 28 and 56 days. Results indicated that the bacteria significantly improved the mechanical properties of hardened concrete. SHC4 and SHC8 exhibited a compressive strength increase of 8% and 14% at 28 days and 15% and 19% at 56 days compared to NC0. This strength increase resulted from permeable voids and water absorption reduction, as well as an improved aggregate-to-mortar ITZ bond due to the formation of bacteria-produced CaCO3, which filled the voids. Reduction in permeable voids and water absorption were 7% to 17%, while density improvement was up to 10% at 28 days. A higher bacteria content consequently produced a better void-filling mechanism. The SHC8 with 8% Bacillus megaterium was proven more effective than SHC4. The 56-day specimens revealed that a significant concrete performance enhancement resulted from the development of CaCO3 deposits over time. It is interesting for further studies to determine the bacteria effectiveness convergence as a function of hardening time. This research highlights the potential of biological approach methods for developing sustainable and resilient construction materials.
7.
Bobby Rio Indriyantho; Joko Purnomo; Purwanto; Marc Ottele; Ay Lie Han; Buntara Sthenly Gan
Multicriteria Sensitivity Analysis for Numerical Model Validation of Experimental Data Journal Article
In: International Journal of Technology (IJTech) , vol. 15, no. 6, 2024.
@article{nokey,
title = {Multicriteria Sensitivity Analysis for Numerical Model Validation of Experimental Data},
author = {Bobby Rio Indriyantho and Joko Purnomo and Purwanto and Marc Ottele and Ay Lie Han and Buntara Sthenly Gan
},
url = {https://ijtech.eng.ui.ac.id/article/view/7146#abstract},
year = {2024},
date = {2024-11-01},
journal = {International Journal of Technology (IJTech) },
volume = {15},
number = {6},
abstract = {Sensitivity analysis is a decisive step in experimental and numerical structural mechanics. The analysis of structural model quantifies the importance of each input parameter, potential interaction and effects on structural response. Therefore, this study aimed to help reduce the uncertainty surrounding major variables, providing valuable guidance for conducting future experiments. During the investigation, numerically deterministic sensitivity analysis based on multicriteria model evaluations of load-displacement curves representing actual behavior of the member correctly, were reviewed. Multicriteria model combined the evaluation of peak load, energy dissipation before ultimate loading, and toughness of load-displacement response. The methodology led to a strong sensitivity analysis method, generating an agreement between numerical and experimental responses. Moreover, an investigation of the method was presented for a geopolymer haunch, the numerical model was based on rigid body spring model (RBSM), which enabled precise behavior simulation of reinforced concrete structures. RBSM was refined, enabling in-depth evaluation of stress-strain contours, plasticity index, initial crack formation and crack propagation, as well as RBSM-spring failure modes. The proposed multicriteria sensitivity analysis can be implemented with other simulation methods, such as finite element analysis (FEA) and structural simulation software. The recommended method is applicable to any structural member, where laboratory-tested full-scale specimens were functioning as validation tools. Following the proposed multicriteria sensitivity analysis, experimental load-displacement curves of this study supported the results of numerical RBSM in an acceptable range of error predictions.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Sensitivity analysis is a decisive step in experimental and numerical structural mechanics. The analysis of structural model quantifies the importance of each input parameter, potential interaction and effects on structural response. Therefore, this study aimed to help reduce the uncertainty surrounding major variables, providing valuable guidance for conducting future experiments. During the investigation, numerically deterministic sensitivity analysis based on multicriteria model evaluations of load-displacement curves representing actual behavior of the member correctly, were reviewed. Multicriteria model combined the evaluation of peak load, energy dissipation before ultimate loading, and toughness of load-displacement response. The methodology led to a strong sensitivity analysis method, generating an agreement between numerical and experimental responses. Moreover, an investigation of the method was presented for a geopolymer haunch, the numerical model was based on rigid body spring model (RBSM), which enabled precise behavior simulation of reinforced concrete structures. RBSM was refined, enabling in-depth evaluation of stress-strain contours, plasticity index, initial crack formation and crack propagation, as well as RBSM-spring failure modes. The proposed multicriteria sensitivity analysis can be implemented with other simulation methods, such as finite element analysis (FEA) and structural simulation software. The recommended method is applicable to any structural member, where laboratory-tested full-scale specimens were functioning as validation tools. Following the proposed multicriteria sensitivity analysis, experimental load-displacement curves of this study supported the results of numerical RBSM in an acceptable range of error predictions.
8.
Yanuar Haryanto; Gathot Heri Sudibyo; Laurencius Nugroho; Hsuan-Teh Hu; Ay Lie Han; Fu-Pei Hsiao; Arnie Widyaningrum; Yudi Susetyo
In: Sage Journals, 2024.
@article{nokey,
title = {Flexural performance of the negative moment region in bonded steel-wire-rope-strengthened reinforced concrete T-beams at different prestressing levels},
author = {Yanuar Haryanto and Gathot Heri Sudibyo and Laurencius Nugroho and Hsuan-Teh Hu and Ay Lie Han and Fu-Pei Hsiao and Arnie Widyaningrum and Yudi Susetyo},
url = {https://journals.sagepub.com/doi/10.1177/13694332241268186},
doi = {10.1177/13694332241268186},
year = {2024},
date = {2024-07-30},
journal = {Sage Journals},
abstract = {This work examines the performance of reinforced concrete (RC) beams strengthened using bonded steel wire rope (SWR) at various prestressing levels. The strengthening approach has, however, been applied to the flexural strengthening of RC T-beams in the negative moment region, in order to determine its advantages. For this purpose, four RC T-beams were fabricated and tested under monotonic four-point bending: one control beam (S00), one beam strengthened with non-prestressed SWR (S20), and two beams strengthened with SWR (prestressed at 10% and 20% of their ultimate tensile strength: S21 and S22). The results indicate that the strengthened beams exhibit higher load-carrying capacities. Specifically, the cracking load, yield load, and ultimate load of S20, S21, and S22 increase by 10%–30%, 30%–50%, and 50%–90%, respectively, compared to S00. Additionally, there is an improvement in stiffness and energy absorption capacity. However, these strategies may have a dual effect on the specimens, resulting in a reduction in their ductility index. Finally, the tested beams were replicated using a three-dimensional finite element model, which has proved effective in predicting the behavior of such structures and, therefore, was found to be appropriate for use in future studies.
},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
This work examines the performance of reinforced concrete (RC) beams strengthened using bonded steel wire rope (SWR) at various prestressing levels. The strengthening approach has, however, been applied to the flexural strengthening of RC T-beams in the negative moment region, in order to determine its advantages. For this purpose, four RC T-beams were fabricated and tested under monotonic four-point bending: one control beam (S00), one beam strengthened with non-prestressed SWR (S20), and two beams strengthened with SWR (prestressed at 10% and 20% of their ultimate tensile strength: S21 and S22). The results indicate that the strengthened beams exhibit higher load-carrying capacities. Specifically, the cracking load, yield load, and ultimate load of S20, S21, and S22 increase by 10%–30%, 30%–50%, and 50%–90%, respectively, compared to S00. Additionally, there is an improvement in stiffness and energy absorption capacity. However, these strategies may have a dual effect on the specimens, resulting in a reduction in their ductility index. Finally, the tested beams were replicated using a three-dimensional finite element model, which has proved effective in predicting the behavior of such structures and, therefore, was found to be appropriate for use in future studies.
9.
Henda Febrian Egatama; Nanang Gunawan Wariyatno; Han Ay Lie; Muhammad Zulfikar Adhi Muliawan; Buntara Shently Gan
Quantitative Shaking Evaluation of Bracing-Strengthened and Base-Isolated Buildings Using Seismic Intensity Level Journal Article
In: Proceeding of Engineering and Technology Innovation (PETI), vol. 27, 2024.
@article{nokey,
title = {Quantitative Shaking Evaluation of Bracing-Strengthened and Base-Isolated Buildings Using Seismic Intensity Level },
author = {Henda Febrian Egatama and Nanang Gunawan Wariyatno and Han Ay Lie and Muhammad Zulfikar Adhi Muliawan and Buntara Shently Gan},
url = {https://ojs.imeti.org/index.php/PETI/article/view/13578},
doi = {10.46604/peti.2024.13578 },
year = {2024},
date = {2024-06-30},
journal = {Proceeding of Engineering and Technology Innovation (PETI)},
volume = {27},
abstract = {In current design practice, the seismic strength design of buildings is commonly based on the strength concept, lacking a quantitative evaluation tool that can show the performance of the buildings during earthquakes. This paper demonstrates the application of seismic intensity level (SIL) as a quantitative evaluation tool for aseismic building performance. A simulation test is conducted on three categories of building-frame: non-strengthened (NA), bracing-strengthened (BS), and base-isolated (BI), subjected to a north-south (N-S) 1940 El Centro seismic wave. The criteria evaluated include maximum acceleration, energy dissipation, and the measured seismic intensity level (m-SIL). The effect of strengthening methods is compared based on those criteria. The results show that despite the apparent reduction in structural response metrics, the SIL value diminishes more substantially for base isolators (4.5 level decrease) than bracing (0.4 level decrease). This confirms that SIL provides higher consistency results and is straightforward to comprehend.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
In current design practice, the seismic strength design of buildings is commonly based on the strength concept, lacking a quantitative evaluation tool that can show the performance of the buildings during earthquakes. This paper demonstrates the application of seismic intensity level (SIL) as a quantitative evaluation tool for aseismic building performance. A simulation test is conducted on three categories of building-frame: non-strengthened (NA), bracing-strengthened (BS), and base-isolated (BI), subjected to a north-south (N-S) 1940 El Centro seismic wave. The criteria evaluated include maximum acceleration, energy dissipation, and the measured seismic intensity level (m-SIL). The effect of strengthening methods is compared based on those criteria. The results show that despite the apparent reduction in structural response metrics, the SIL value diminishes more substantially for base isolators (4.5 level decrease) than bracing (0.4 level decrease). This confirms that SIL provides higher consistency results and is straightforward to comprehend.
10.
Henda Febrian Egatama; Bobby Rio Indriyantho; Ay Lie Han; Eiji Nouchi; Emy Shinta Wijayaningsih; Buntara Sthenly Gan
Quantification of Shaking-based Criteria for Evaluating Aseismic Performance of House and Building Journal Article
In: Iranian Journal of Science and Technology, Transactions of Civil Engineering, 2024.
@article{nokey,
title = {Quantification of Shaking-based Criteria for Evaluating Aseismic Performance of House and Building},
author = {Henda Febrian Egatama and Bobby Rio Indriyantho and Ay Lie Han and Eiji Nouchi and Emy Shinta Wijayaningsih and Buntara Sthenly Gan },
url = {https://link.springer.com/article/10.1007/s40996-024-01411-y},
doi = {https://doi.org/10.1007/s40996-024-01411-y},
year = {2024},
date = {2024-04-17},
journal = {Iranian Journal of Science and Technology, Transactions of Civil Engineering},
abstract = {Based on the 22-year (1996–2018) Japan Meteorological Agency periodical data, the number of human injuries exceeded those deaths due to earthquakes. Similarly, the number of collapsed houses number and buildings is below the number of partly damaged ones. Investigations showed that the cause of human casualties was shaking when strong earthquakes occurred. The collapse of non-structural components, bookcases, machinery equipment, or ceilings as a result of severe shaking is the primary cause of human mortality. The report indicates that the houses and buildings designed by the up-to-date seismic code revisions show adequate resistance against the earthquake. However, the latest codes fail to protect the human casualties inside the houses and buildings. Present works proposed quantifying shaking-based criteria for evaluating houses and buildings’ seismic intensity scale (SIS). Using SIS could benefit the designer in selecting the appropriate aseismic methods. This SIS-based criterion is verified by evaluating a 5-story earthquake-proof frame structure equipped with two aseismic devices. The results show that the maximum acceleration reduction was 77.7% and 88.6% for a frame with a tuned mass damper (TMD) and a base isolator (BI) consecutively. The decrease in SIS number for a frame with BI is more significant compared to TMD. The study concluded that BI is more effective than TMD in reducing the shaking of houses and buildings. The objective of SIS computing is to find measures or actions that can minimize the risk of human casualties and evaluate the best performances of aseismic devices in houses and buildings during earthquakes.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Based on the 22-year (1996–2018) Japan Meteorological Agency periodical data, the number of human injuries exceeded those deaths due to earthquakes. Similarly, the number of collapsed houses number and buildings is below the number of partly damaged ones. Investigations showed that the cause of human casualties was shaking when strong earthquakes occurred. The collapse of non-structural components, bookcases, machinery equipment, or ceilings as a result of severe shaking is the primary cause of human mortality. The report indicates that the houses and buildings designed by the up-to-date seismic code revisions show adequate resistance against the earthquake. However, the latest codes fail to protect the human casualties inside the houses and buildings. Present works proposed quantifying shaking-based criteria for evaluating houses and buildings’ seismic intensity scale (SIS). Using SIS could benefit the designer in selecting the appropriate aseismic methods. This SIS-based criterion is verified by evaluating a 5-story earthquake-proof frame structure equipped with two aseismic devices. The results show that the maximum acceleration reduction was 77.7% and 88.6% for a frame with a tuned mass damper (TMD) and a base isolator (BI) consecutively. The decrease in SIS number for a frame with BI is more significant compared to TMD. The study concluded that BI is more effective than TMD in reducing the shaking of houses and buildings. The objective of SIS computing is to find measures or actions that can minimize the risk of human casualties and evaluate the best performances of aseismic devices in houses and buildings during earthquakes.