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An Investigation of Hydro-morphology Contributory Factors in Flooding and Sedimentation Problems on the Krueng Buloh River, Indonesia

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Open civil engineering Journal 2023年 17卷

作者： Listia, Vina Munirwansyah, Munirwansyah Azmeri, Azmeri Yulianur, Alfiansyah Doctoral Program School of Engineering Post Graduate Program Universitas Syiah Kuala Banda Aceh Darussalam 23111 Indonesia Department of Civil Engineering Faculty of Engineering Universitas Syiah Kuala Banda Aceh Darussalam 23111 Indonesia

Introduction: Process-based river hydrology and morphological analyses are infrequent, especially in developing countries. Climate change and the expected occurrence of major floods and erosion that could threaten the safety of nearby and downstream settlements, especially in areas that are very sensitive and affected by global warming, have made this kind of investigation necessary. Methods: The watershed of the River Krueng Buloh is prone to severe flooding, which has many social and economic effects on the villages nearby, such as the loss of crops and the destruction of buildings. However, the hydro-morphology and fluctuation of this river have not yet been studied. This research aims to determine which factors influence the stability of a river channel in the downstream region of the Krueng Buloh watershed following flooding or erosion. Results: To achieve this objective, field, and satellite-based observations of the hydro-morphology of a Krueng Buloh watershed have been performed. The investigation reveals that floods and sediment accumulation in the floodplain were triggered by excessive rainfall, the meandering of the river, and the riverbank soil type. Conclusion: The conclusions and methods given can be used to evaluate flooding and sedimentation in rivers for future operations to protect and preserve rivers. © 2023 Listia et al.

关键词： Erosion Flood Hydrology Morphology River Sedimentation Watershed

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Study of Machine Learning Techniques for Damage Identification in a Beam 10th

Study of Machine Learning Techniques for Damage Identifica...

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10th International Conference on Wave Mechanics and Vibrations, WMVC 2022

作者： da Silva Coelho, Jefferson de Sousa, Amanda Aryda Silva Rodrigues Machado, Marcela Rodrigues Dutkiewicz, Maciej Department of Mechanical Engineering University of Brasília Campus Universitário Darcy Ribeiro Faculdade de Tecnologia - Asa Norte DF Brasília Brazil Post-Graduate Program - Integrity of Engineering Materials University of Brasília Campus Universitário Darcy Ribeiro Faculdade de Tecnologia - Asa Norte DF Brasília70910-900 Brazil Faculty of Civil Environmental Engineering and Architecture University of Science and Technology Bydgoszcz85-796 Poland

ISBN: (纸本)9783031157578

Damage is defined as any change to the material, geometry or boundary condition that can modify the structure’s properties or response. In the past, damage identification was performed through periodical inspection, non-destructive testing/non-destructive evaluation, or visual observation. Structural health monitoring (SHM) has emerged to transition from offline damage identification to near real-time and online damage assessment. Hence, SHM is a damage detection strategy to monitor a structure for a period using a series of continuous measurement devices, which then collect the system’s characteristics and subsequently perform statistical analysis to assess the current circumstances and health of the structure. One of the first steps for the study of SHM is damage detection followed by monitoring. Machine Learning (ML) techniques can be used to develop viable algorithms to make potential predictions. ML algorithms are therefore providing the tools needed to enhance the capabilities of SHM systems and provide intelligent solutions to past challenges. Preliminary studies have reviewed that the extension of ML into SHM has dramatically increased the system’s capabilities, providing innovative solutions to different research challenges. This work conducts a study of the use of ML to identify damage in a beam and discuss the challenge of usage, performance and implementation of each technique. © 2023, The Author(s), under exclusive license to Springer Nature Switzerland AG.

关键词： Decision trees

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Flood Susceptibility Mapping using GIS Based on Fuzzy AHP Method in Keureuto River Basin, Aceh

Flood Susceptibility Mapping using GIS Based on Fuzzy AHP Me...

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Science and Information Technology in Smart Administration (ICSINTESA), International Conference of

作者： Maimun Rizalihadi Alfiansyah Yulianur Yuwaldi Away Ella Meilianda Doctoral Program. Post Graduate. Program. Syiah Kuala University Banda Aceh Indonesia Civil Engineering Department Syiah Kuala University Banda Aceh Indonesia Elect. and Compt. Eng. Department Syiah Kuala University Banda Aceh Indonesia

ISBN: (数字)9798350376111

ISBN: (纸本)9798350376128

Flood susceptibility mapping become crucial for describing flood risk zones and development mitigation actions. By means of a multi-criteria decision analysis-Analytical Hierarchy Process (MCDA-AHP), this study examined flood-inundation of Keureuto watershed in North Aceh. The study employed a mixture of AHP and GIS (Geographic Information System) on a fuzzy environment, and tested with the field observation by mean of AUC-ROC method to see its accuracy. Eleven key criteria that can trigger floods were chosen: rainfall, flow accumulation, river density, distance to the river, elevation, slope, TWI, LULC, soil type, NDVI, and curvature. The significance of all of criteria was arranged based on the weights which is determined using Fuzzy-AHP (FAHP) pairwise comparison matrix (PCM). The highest flood-triggering criteria were rainfall (0.199), TWI (0.159), flow accumulation (0.143), distance to rivers (0.094), and slope (0.091). Based on fuzzy overlay, the area of $323.747 \mathrm{~km}^{2}\left(34.635 \%\right.$ of $934.745 \mathbf{k m}^{2}$ of total area) was high to very high flood susceptibility which is mostly concentrated in downstream of river basin, while the area of $610.998 \mathrm{~km}^{2}(65.365 \%$ of the total area) has moderate to very low flood susceptibility. where the model achieved a higher AUC value of $\mathbf{7 7. 8 9 \%}$, indicating better performance. It is proved that the FAHP model is very good for forecasting flood-inundation areas in the Keureuto River basin.

关键词： Phase change materials Rain Accuracy Prevention and mitigation Watersheds Soil Predictive models Rivers Floods Geographic information systems

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Assessing the Performance of Eggshell Ash as a Sustainable Bitumen Modifier

SSRN

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SSRN 2023年

作者： Syammaun, Tamalkhani Husaini, Husaini Abdullah, Abdullah Isya, Muhammad Rachman, Firmansyah Doctoral Program School of Engineering Post Graduate Program Universitas Syiah Kuala Banda Aceh23111 Indonesia Department of Civil Engineering Universitas Muhammadiyah Aceh Banda Aceh23123 Indonesia Department of Mechanical Engineering Universitas Syiah Kuala Banda Aceh23111 Indonesia Department of Civil Engineering Universitas Syiah Kuala Banda Aceh23111 Indonesia

The disposal of eggshells in landfills presents an ongoing global environmental issue that demands immediate attention. However, a promising solution lies in utilizing eggshells as modifiers in bitumen binders, offering a sustainable approach to alleviating this burden. This study focuses on crushing eggshells to produce eggshell ash, which is then explored as a potential modifier in bitumen binders. The objective is to evaluate the properties of modified bitumen binders incorporating eggshell waste sourced from the food industry and examine their application in bitumen engineering. Employing a 60/70 penetration-grade asphalt binder as the research foundation, the optimal weight percentage of eggshell ash in the bitumen is determined, considering four levels (5%, 7%, 10%, and 12%) and two different heating temperatures (100°C and 200°C). Several tests are conducted to comprehensively evaluate the eggshell ash, including SEM-EDS and FTIR analyses, providing valuable technical insights into its properties. Additionally, dynamic shear rheometer (DSR) measurements are employed to analyze the characteristics of the bitumen incorporating eggshell ash. The primary oxide group present in the eggshell ash is calcium carbonate (CaCO3). Notably, higher concentrations of eggshell ash enhance the resistance of bitumen binders to high temperatures, as indicated by the penetration index results. Furthermore, DSR testing reveals that the addition of eggshell ash significantly increases the rigidity of the bitumen binders, resulting in improved resistance to deformation. © 2023, The Authors. All rights reserved.

关键词： Binders

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Remote Sensing Applied to the Extraction of Road Geometric Features Based on Optimum Path Forest Classifiers, Northeastern Brazil

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Journal of Geographic Information System 2020年第1期12卷 15-44页

作者： Márcia Macedo Maria Maia Emilia Kohlman Rabbani Oswaldo Lima Neto Post-Graduate Program in Civil Engineering UFPE Pernambuco Brazil Post-Graduate Program in Civil Engineering UPE Pernambuco Brazil

One of the principal difficulties related to road safety management in Brazil is the lack of data on road projects, especially those on rural roads, which makes it difficult to use road safety studies and models from other countries as a reference. Updating road networks through the use of hyperspectral remote sensing images can be a good alternative. However, accurately recognizing and extracting hyperspectral images from roads has been recognized as a challenging task in the processing of hyperspectral data. In order to solve the aforementioned challenges, Hyperion hyperspectral images were combined with the Optimum Forest Path (OPF) algorithm for supervised classification of rural roads and the effectiveness of the OPF and SVM classifiers when applied to these areas was compared. Both classifiers produced reasonable results, however, the OPF algorithm outperformed SVM. The higher classification accuracy obtained by the OPF was mainly attributed to the ability to better distinguish between regions of exposed soil and unpaved roads.

关键词： Roads Multispectral Images Hyperspectral Images Optimum Path Forest Algorithm

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Numerical analysis of the influence of the contact boundary condition and specimen geometry on concrete compressive strength

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Procedia Structural Integrity 2023年 47卷 261-267页

作者： Caroline Bremm Luísa Inda Leandro Ferreira Friedrich Sabrina Vantadori Ignacio Iturrioz Luis Kosteski Engineering Post Graduation Program Federal University of Pampa Av. Tiaraju 810 Alegrete 97546-550 Brazil Civil Engineering Graduate Program Federal University of Pampa Av. Tiaraju 810 Alegrete 97546-550 Brazil Program of Mechanical Pos-Graduation Federal University of Rio Grande do Sul Sarmento Leite 425 Porto Alegre 90040-060 Brazil Department of Engineering & Architecture University of Parma Parco Area delle Scienze 181/A 43124 Parma Italy

In the present paper, the influence of the contact boundary condition and specimen geometry on the concrete compressive strength is numerically investigated by using a version of the Lattice Discrete Element Method (LDEM), implemented on Abaqus/Explicit. More precisely, two types of contact boundary conditions are considered and, for each of them, three different slenderness levels (height/width ratio - h/b) are analyzed (that is, h/b = 0.5, 1.0, and 2.0) by considering a square cross-section. Moreover, for h/b = 2.0, a circular cross-section is also examined. Two models are developed: one by using the LDEM and the other by using a hybrid model, combining Finite Elements and LDEs. The results show that both the boundary conditions and the sample geometry influence the axial compressive strength.

关键词： Abaqus concrete compressive strength Lattice Discrete Element Method (LDEM)

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Effect of Method and Duration of Curing on the Compressive Strength of the Lime-Fly Ash Geopolymer Concrete 1

Effect of Method and Duration of Curing on the Compressive S...

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1st Progress in Science and Technology Research Symposium, PSTRS 2019

作者： Adam, Andi Arham Akifa, Sri Nur Siregar, Atur P.N. Mustofa Department of Civil Engineering Tadulako University Indonesia Post-Graduate Program Tadulako University Indonesia Department of Mechanical Engineering Tadulako University Indonesia

The use of lime to produce ambient cured Geopolymer concrete is one of a practical solution to avoid heat curing in the production of geopolymer concrete. The addition of lime in the geopolymer system will add another hardened mechanism, i.e. hydration in addition to condensation-polymerisation. This research aims to determine the influence of air and water curing on the strength of geopolymer concrete which uses class F fly ash and lime as raw materials. The geopolymer concrete was produced by varying the activator (sodium silicate and sodium hydroxide) with the variation of the activator to binder ratio of 0.45, 0.50, 0.55, and 0.60. Five per cent of the fly ash was replaced by slaked lime and the water added to the mix to maintain the ratio of water to solid (activator + binder) to 0.32. The test specimens were 100 mm dia x 200 mm height cylinder. Water-immersion curing was performed for 7, 14, and 21 days and the compressive strength test was done at 28 days. The results show that there is a difference in the curing process between the geopolymer concrete and the normal concrete. In the geopolymer concrete, there is a decrease in compressive strength if soaked for seven days and recovered with the increase in the age of immersion. Whereas for normal concrete, the compressive strength continues to increase with increasing age of immersion. © Published under licence by IOP Publishing Ltd.

关键词： Compressive strength

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Assessment of Stainless Steel Tubular T-joints Under Chord Sidewall Failure Mode by a Semi-analytical Formulation

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ce/papers 2022年第4期5卷 574-583页

作者： Nogueira, Mateus M. de Lima, Luciano R. O. da S. Vellasco, Pedro C. G. Young, Ben PGECIV - Civil Engineering Post-Graduate Program UERJ – State University of Rio de Janeiro Brazil Structural Engineering Department UERJ – State University of Rio de Janeiro Brazil Department of Civil and Environmental Engineering The Hong Kong Polytechnic University Hong Kong

There are numerous benefits of tubular profiles that make them increasingly used in civil engineering. At the same time, stainless steel is a material with excellent properties and high corrosion resistance. However, stainless steel's high initial material cost has limited its use primarily to specialist and prestige applications, which makes it necessary to develop more accurate design rules for this material. When tubular profiles are used, it is necessary to assess the joint strengths, considering that they can fail by different mechanisms. The present work aims to develop a semi-analytical formulation to predict stainless steel tubular T-joint resistances. Joints with the brace-to-chord width ratio equal to 1 were considered in this study;therefore, the failure occurs in the chord sidewall. To assess the sidewall instability critical load, the exact stress fields were determined using Mathieu's theory, and then the Ritz energy method was applied. Considering that the joints are made of stainless steel, the next step is to transform the load found from linear to the non-linear regime. For that, a new formulation based on Ramberg-Osgood equations was developed. Finally, the results obtained from the proposed method were compared with the experimental results obtained by Feng and Young (2008) and the results from the main current standards and literature. It was observed that the proposed method presented satisfactory results, while the predictions from design codes were, in general, very conservative. © 2022 Ernst & Sohn GmbH.

关键词： Failure (mechanical)

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Relative importance of pathologies in the severity of facade degradation

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Journal of Building Pathology and Rehabilitation 2020年第1期5卷 1-10页

作者： Bauer, Elton Piazzarollo, Carla Bozzi de Souza, Jéssica Siqueira dos Santos, Danilo Gonçalves Post-Graduate Program in Structures and Civil Construction Civil and Environmental Engineering Department University of Brasília Campus Universitário Darcy Ribeiro Asa Norte Brasília DF Brazil

The facade is the main protective barrier against the atmospheric agents acting in a building. Many times, as a result of these agents, the facade manifests pathologies that lead to the loss of performance of the external wall claddings. This article aims to establish and score the importance of the pathologies involved in the cement mortars rendering. The probable causes and the influence on the performance decrease over time are analyzed. The methodology is based on the survey and mapping of the pathologies observed in field survey, correlating these pathologies with probable causes and implications for the system performance. Among the active pathologies, cracks had both a higher intensity of occurrence and a greater gravity compared to the others. Some pathologies, such as detachment and efflorescence, although of great importance in the degradation, are little observed in the studied buildings. As a result, is presented a scale of importance of pathologies, which has great application for the development of facade degradation models. © 2020, Springer Nature Switzerland AG.

关键词： Cement mortar Degradation External wall claddings Facades Pathologies

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Antioxidant system alterations and oxidative stress caused by polyfluoroalkyl substances (PFAS) in exposed biota: a review

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Science of the Total Environment 2025年 977卷 179395页

作者： Soares, Lorena Oliveira Souza de Araujo, Gabriel Farias Gomes, Thais Braga Júnior, Sidney Fernandes Sales Cuprys, Agnieszka Katarzyna Soares, Raquel Moraes Saggioro, Enrico Mendes Laboratory of Environmental Health Assessment and Promotion Oswaldo Cruz Institute Oswaldo Cruz Foundation Av. Brasil 4365 RJ Rio de Janeiro21045-900 Brazil Post-Graduate Program in Public Health and Environment Sergio Arouca National School of Public Health Oswaldo Cruz Foundation Av. Leopoldo Bulhões 1480 RJ Rio de Janeiro21041-210 Brazil Faculty of Science and Technology Norwegian University of Life Sciences P.O. Box 5003 Ås1432 Norway Post-Graduate Program in Environmental Technology and Water Resources Department of Civil and Environmental Engineering – FT University of Brasília Darcy Ribeiro Campus Via L3 Norte DF Brasília70910-900 Brazil

Contamination of aquatic and terrestrial organisms by Perfluoroalkyl substances (PFAS), emerging contaminants, is widespread, as these compounds are present in water, soil, air, and food, owing to their environmental persistence. PFAS exposure induces biochemical process alterations associated with the disruption of the antioxidant defense system in several species. This review aims to discuss how PFAS-induced antioxidant system alterations lead to changes in biochemical processes in different organisms exposed to these pollutants. This disruption, then leads to an imbalance in antioxidant defense systems, contributing to the formation of reactive oxidative species (ROS), which, in turn, can be exacerbate oxidative stress, induce cellular damage, enhance lipid peroxidation, destabilize lysosomal membranes, and cause genotoxic effects, ultimately compromising DNA integrity. In acute tests, PFAS have led to mortality, growth inhibition, diminished behavioral and locomotor abilities, and reproductive impairment. PFAS-induced effects differ with varying species or types of substances, and further bioaccumulation through food chains exacerbates environmental contamination, carrying considerable risks. These findings demonstrate the complex and enduring impact of PFAS on environmental health, emphasizing the importance of this review in corroborating studies on sub-lethal toxicity in exposed organisms and how these effects reflect on the environment. © 2025 Elsevier B.V.

关键词： Biotic

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