@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}

}

@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}

}

@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}

}

@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}

}

@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}

}