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Unsaturated Strength of Tage Tuff and Its Water Retention Drying Curve

Zairyo/Journal of the Society of Materials Science, Japan 2024年第3期73卷 212-219页

作者： Kotabe, Haruhiko Togashi, Yota Hatakeyama, Ken Osada, Masahiko Civil and Environmental Engineering Program Graduate School of Science and Engineering Saitama University Shimo-Okubo Sakura-ku Saitama338-8570 Japan Integrated Technical Support Center Research Organization Saitama University Shimo-Okubo Sakura-ku Saitama338-8570 Japan

Strength loss of sedimentary rocks due to water content changes is an important issue in the civil engineering field. Assuming disasters associated with rainfall and drying, it is important to identify unsaturated strength properties for gradually varying moisture contents. Water retention curves are needed to describe unsaturated strength properties. The high suction acting in the case of rock presents a challenge in identifying the suction. In particular, identifying the water retention drying path is difficult. This study propose a method to identify the drying paths using uniaxial compressive strength and tensile strength of Brazilian test. Uniaxial compression and Brazilian tests were performed on specimens with varying water content in the drying pass to investigate changes in their mechanical properties. Strength and stiffness were found to be approximately halved in the wet condition compared to the dry condition. Simplified Mohr-Coulomb failure criteria are also identified using uniaxial compressive and tensile strength. The cohesion decreases with increasing water content, while the angle of shear resistance is independent of changes in water content. Suction at each saturation level was back-analyzed using the detected cohesion and shear resistance angles to identify the water retention drying curve. The water retention drying curves identified were compared with the water retention wetting curve identified by another method to confirm the validity of the proposed method. ©2024 The Society of Materials Science, Japan.

关键词： Sedimentary rocks

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Insights on the irrigation conveyance efficiency of three canal systems for improving agricultural sustainability in Sri Lanka

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Water Supply 2025年第5期25卷 807-824页

作者： Sumanasekara, Harindu S. Jayasinghe, Ananda Herath, Anjana B. Siriwardhana, Kushan D. Imbulana, Indra L. Mullegamgoda, Kithsiri Herath, Ruchiru Paranavithana, Ganila Rathnayake, Upaka 07 Colombo Sri Lanka Improving System Efficiencies and Water Productivity Project Mahaweli Water Security Investment Program 10 Colombo Sri Lanka Engineering and Design Center Faculty of Engineering University of Peradeniya Peradeniya20400 Sri Lanka Water Resources Management and Soft Computing Research Laboratory Millennium City Athurugiriya10150 Sri Lanka Department of Civil Engineering Faculty of Engineering Technology The Open University of Sri Lanka Nugegoda10250 Sri Lanka Department of Civil Engineering and Construction Faculty of Engineering and Design Atlantic Technological University SligoF91 YW50 Ireland

System conveyance efficiency of the canals is highly important in planning new irrigation development schemes. Enhancing the efficiencies directly influences sustainable agricultural practices. This study, conducted in 2022–2023, assessed conveyance losses in three major irrigation schemes in Sri Lanka: Maduru Oya, Hurulu Wewa, and Minipe Left Bank Canal. The research aimed to quantify current conveyance losses and identify factors influencing efficiency to inform rehabilitation efforts. Field measurements were taken using the float method to determine flow rates at multiple points along selected canals. Conveyance losses were calculated as the percentage difference in flow between measurement points. Results showed significant variations in losses across the three systems: Maduru Oya averaged 27.8% (standard deviation (SD) = 6.03%), Hurulu Wewa 26.5% (SD = 20.4%), and Minipe Left Bank Canal 33.1% (SD = 15.4%) for the D47 canal and 27.7% (SD = 23.7%) for the D32 canal. Factors observed to influence conveyance losses included canal lining condition, soil texture, and topographical features such as elevation differences between drainage and field canals. The study concludes that targeted rehabilitation efforts, particularly increased lining in high-loss areas and improved maintenance in tail-end sections, could substantially improve system efficiency. These findings provide crucial data for irrigation planners and policymakers in Sri Lankan agriculture. © 2025 The Authors.

关键词： Infiltration

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Densified mixture design algorithm: A novel mix design concept and its application for green concretes incorporating industrial by-products

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Environmental Progress and Sustainable Energy 2023年第4期42卷 e14086-e14086页

作者： Nguyen, Tan-Hung Limongan, Andrian H. Nguyen, May Huu Hwang, Chao-Lung Huynh, Trong-Phuoc Department of Civil Engineering Can Tho University of Technology Can Tho Viet Nam Department of Civil and Construction Engineering National Taiwan University of Science and Technology Taipei Taiwan Department of Bridge and Tunnel Faculty of Civil Engineering University of Transport Technology Hanoi Viet Nam Civil and Environmental Engineering Program Graduate School of Advanced Science and Engineering Hiroshima University Hiroshima Japan Taiwan Building Technology Center National Taiwan University of Science and Technology Taipei Taiwan Faculty of Civil Engineering College of Engineering Can Tho University Can Tho Viet Nam

Despite the fact that densified mixture design algorithm (DMDA) has been identified as a promising tool for green concrete mix design, its use in real practice has still been minimal worldwide. Due to the lack of precise information on DMDA computation in earlier studies, this work proposes DMDA including fly ash and ground granulated blast-furnace slag as a viable way to improve the long-term performance of green concrete. To encourage the use of DMDA, this study offers a detailed description of the DMDA mix design, as well as a step-by-step standard operating procedure and an empirical example of the computation. Assessments of the long-term performance of green mixtures (self-consolidating concrete and high-performance concrete) and ordinary Portland cement concrete (designed using the conventional method of American Concrete Institute, ACI) were made. Performances of the ACI (O6000 mixture) and DMDA concretes (S6000 and H6000 mixtures) were then compared in terms of compressive strength, elastic modulus, shrinkage, and creep strain. As a result, all of the concrete samples attained the target strength of above 41 MPa (6000 psi) after only 28 days. Moreover, compressive strength, elastic modulus, shrinkage, and creep strain increased significantly in all of the concretes over curing time. Importantly, the experimental results confirmed that both types of DMDA concrete exhibited higher compressive strength and better long-term performance than the ACI concrete under elastic modulus, creep, and shrinkage aspects. © 2023 American Institute of Chemical Engineers.

关键词： Compressive strength

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Influence of rice husk ash and hybrid fiber on engineering properties of densified high-performance fiber-reinforced concrete

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Proceedings of the Institution of Mechanical Engineers, Part L: Journal of Materials: Design and Applications 2023年第11期237卷 2845-2857页

作者： Vo, Duy-Hai Nguyen, Minh-Hieu Nguyen, May Huu Hwang, Chao-Lung Huynh, Trong-Phuoc The University of Danang University of Technology and Education Danang Viet Nam Vinh Long Department of Construction Vinh Long Viet Nam Civil and Environmental Engineering Program Graduate School of Advanced Science and Engineering Hiroshima University Hiroshima Japan Department of Bridge and Tunnel Faculty of Civil Engineering University of Transport Technology Hanoi Viet Nam Taiwan Building Technology Center National Taiwan University of Science and Technology Taipei Taiwan Faculty of Civil Engineering College of Engineering Can Tho University Can Tho Viet Nam

Conventional concrete significantly affects the environment due to high CO2 emission into the atmosphere during the production process. In order to improve concrete performance and arrest the incidence of global warming, the use of additive materials for cement replacement has been promoted worldwide. This study was designed to investigate the mechanical properties of high-performance fiber-reinforced concrete (HFRC) produced using rice husk ash (RHA) and hybrid fiber (HF) in accordance with the densified mixture design algorithm (DMDA) mix design method. Samples were produced using RHA as a direct replacement for cement at 10%, 20%, and 30%. HF, comprising steel and polypropylene fibers, was added (by volume) to the 20% RHA group mixture to improve the HFRC sample properties. Based on the experimental results, higher RHA contents had a generally negative effect on the fresh properties of the HFRC mixtures. Compressive strength values ranged from 53 to 72 MPa with various RHA and HF content. RHA replacement levels up to 20% had an insignificant effect on the strength development and dynamic modulus of the HFRC samples. However, the addition of HF improved splitting tensile strength, flexural strength, and dynamic modulus remarkably at all curing ages. Furthermore, the 91-day drying shrinkage was in the ranges of 0.032%–0.039% and 0.023%–0.034% using different RHA and HF levels, respectively. Increasing both RHA and HF contents significantly reduced drying shrinkage in the samples. Multivariable regression was also performed, clarifying that all tested results were consistent and had good correlations. The results of this study also provide a potentially effective use for abundantly available industrial waste products such as fly ash (FA) and RHA to promote the production of greener and more sustainable concrete. © IMechE 2023.

关键词： Bending strength

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Spatially differentiated life cycle assessment of Thailand's transport: The implications from country-specific factors and alternative technologies

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Sustainable Production and Consumption 2025年 57卷 319-340页

作者： Chotanapund, Vitoon Gheewala, Shabbir H. Strezov, Vladimir Huda, Nazmul Mungkalasiri, Jitti Prapaspongsa, Trakarn Graduate Program in Environmental and Water Resources Engineering Department of Civil and Environmental Engineering Faculty of Engineering Mahidol University Nakhon Pathom Thailand School of Natural Sciences Faculty of Science and Engineering Macquarie University NSW2109 Australia King Mongkut's University of Technology Thonburi Bangkok Thailand Center of Excellence on Energy Technology and Environment Ministry of Higher Education Science Research and Innovation Ministry of Education Bangkok Thailand School of Engineering Faculty of Science and Engineering Macquarie University NSW2109 Australia Pathum Thani Thailand

This study proposed country-specific characterisation factors (CFs) for Thailand by modifying the Thai Spatially Differentiated Life Cycle Impact Assessment (ThaiSD) method and introducing monetary conversion factors to express environmental impacts in Thai Baht. Five impact categories were fully parameterised, including fine particulate matter formation (PMF), human toxicity (both cancer and non-cancer) (HTc and HTnc), freshwater ecotoxicity (FET), and water scarcity (WS). Other spatialised CFs were selected from regionalisation models in ReCiPe2016 and IMPACT World+. When comparing the use of country-specific CFs with global average, the impact scores for PMF, HTc, HTnc, FET, photochemical ozone formation and terrestrial acidification demonstrated notably different levels, ranging from ±25 to ±50 %. The developed method was then applied to assess environmental impacts and costs of Thailand's transport sector, encompassing freight and passenger transport across roadway, railway, waterway, and aviation. Climate change (CC) was significantly attributed to human health and ecosystem quality impacts, while the major contributor to resource scarcity impact was fossil resource scarcity (FS). In some scenarios, non-exhaust emissions, particularly from freight trucks, accounted for 40–60 % of the total PMF impacts. Environmental costs of freight and passenger transport in Thailand were 0.08–3.64 Thai Baht per tonne-kilometre and 0.01–0.81 Thai Baht per passenger-kilometre, respectively. Among transport modes, trains were found to be the most environmentally favourable option for both passenger and freight transport, while aviation had the highest environmental impact for freight transport. In contrast, passenger aviation had a comparable environmental burden to passenger cars due to optimised occupancy rates. Despite the efficiency of modern internal combustion engine vehicles (ICEVs), particularly Euro 5 and 6, employing blended biodiesel was less effective in comparison

关键词： Freight transportation

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THE SILT FENCE: KEEPING SEDIMENT WHERE IT BELONGS

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Public Roads 2023年第2期87卷 8-11页

作者： Whitman, J. Blake Perez, Michael A. Smith, Brian L. Middle Tennessee State University The School of Concrete and Construction Management Auburn University ALDOT The Department of Civil and Environmental Engineering Auburn University Construction and Stormwater Management and Oversees the Research Program AU-SRF The FHWA Resource Center Office of Innovation Implementation Illinois State University Northern Illinois University

Managing stormwater to protect the Nation’s waters is a common challenge of highway construction sites. Most water quality problems in lakes and rivers are the result, in part, of stormwater runoff. Typically, grading and earth-disturbing activities during construction require removal of vegetation that dissipates raindrop energy and filters and controls stormwater pollution.

关键词： Grading

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Integration of Small Unmanned Aircraft Systems and Deep Learning for Efficient Airfield Pavement Crack Detection and Assessment

Integration of Small Unmanned Aircraft Systems and Deep Lear...

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International Conference on Transportation and Development 2024: Transportation Safety and Emerging Technologies, ICTD 2024

作者： All Sourav, Md Abdullah Ceylan, Halil Kim, Sunghwan Brynick, Matthew Dept. of Civil Construction and Environmental Engineering Iowa State Univ. AmesIA United States Dept. of Civil Construction and Environmental Engineering and Program for Sustainable Pavement Engineering and Research Iowa State Univ. AmesIA United States Program for Sustainable Pavement Engineering and Research Institute for Transportation Iowa State Univ. AmesIA United States Federal Aviation Administration Airport Pavement R&D Section William J. Hughes Technical Center NJ United States

ISBN: (纸本)9780784485514

Airfield pavement inspection and maintenance are critical aspects of aviation infrastructure, representing a substantial portion of life-cycle costs. Longitudinal, transverse, and diagonal (LTD) cracks;corner breaks;shattered slabs in Portland cement concrete (PCC) pavement;and longitudinal and transverse (L&T) cracks of asphalt concrete (AC) pavement consist of most of the airfield pavement distresses. Traditional airfield pavement inspection methods are manual, time-consuming, laborious, and reliant on the inspector’s experience, leading to increased expenses and safety risks. This research explores the potential to automatically identify those distresses in red-green-blue images using four variants of deep learning (DL) model YOLOv8, ranging from nano to large. YOLOv8 is a widely used off-the-shelf DL object detection model that allows rapid training and easy execution. A DL training dataset of 5,273 small uncrewed aircraft systems (sUAS) collected images was developed. The transfer learning technique was used, and the dataset passed through each model 100 times for adequate training. The model exhibits mean average precision values exceeding 0.65, with varying processing times. Such accuracy showed that crack-related distress detection using DL models could enhance airfield pavement inspection efficiency. © ASCE.

关键词： Drones

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Machine learning-based modeling of surface water temperature dynamics in arctic lakes

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Environmental Science and Pollution research 2024年第49期31卷 59642-59655页

作者： Kim, Hyung Il Kim, Dongkyun Salamattalab, Mohammad Milad Mahdian, Mehran Bateni, Sayed M. Noori, Roohollah DL E & amp C Civil Business Division Donuimun D Tower 134 Tongil-Ro Jongno-Gu Seoul Korea Republic of Department of Civil and Environmental Engineering Hongik University Mapo-Gu Seoul Korea Republic of School of Civil Engineering Iran University of Science and Technology Tehran Narmak*** Iran Department of Civil Environmental and Construction Engineering and Water Resources Research Center University of Hawaii at Manoa HonoluluHI United States Graduate Faculty of Environment University of Tehran Tehran*** Iran Faculty of Governance University of Tehran Tehran*** Iran UNESCO-UNISA Africa Chair in Nanoscience and Nanotechnology College of Graduate Studies University of South Africa Muckleneuk Ridge Pretoria392 South Africa

Lake surface-water temperature (LSWT) regulates physical and biochemical processes in lakes. Therefore, understanding the LSWT dynamics is important, especially in Arctic zone since the region is experiencing a warming rate that is greater than the Earth’s average. However, regular measurements of LSWT in the remote Arctic lakes always face difficulties or cannot be done by satellites accurately due to the cloud cover and their limited spatiotemporal resolution. Here, we used a historically rich data (1960–2023) to develop four machine learning-based algorithms for the daily LSWT modeling in Lake Inari, situated in Arctic zone, using the air-temperature data. Our results showed that both air-temperature (0.030 °C/yr) and LSWT (0.023m °C/yr) were warming with a rate faster than those in the globe. The long-short-term memory model, with the coefficients of determination varied from 0.96 to 0.98, outperformed other algorithms in modeling of the daily LSWT dynamics in Lake Inari, followed by both support vector regression and neural network tools, and random forest model. As the air-temperature data are widely accessible through synoptic stations and remote sensing techniques, our suggested models can be simply adopted for other Arctic lakes, where the local water-temperature data are often lacking or contain large windows of missing data due to harsh atmospheric conditions and equipment failure. Graphical abstract: (Figure presented.) © The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2024.

关键词： Long short-term memory

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New microbial electrosynthesis system for methane production from carbon dioxide coupled with oxidation of sulfide to sulfate

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Journal of Environmental Sciences 2023年第3期125卷 786-797页

作者： Hiromi Kambara Ha T.T.Dinh Shuji Matsushita Yoshiteru Aoi Tomonori Kindaichi Noriatsu Ozaki Akiyoshi Ohashi Department of Civil and Environmental Engineering Graduate School of EngineeringHiroshima University1–4–1KagamiyamaHigashi-HiroshimaHiroshima 739–8527Japan Faculty of Environment Ho Chi Minh City University of Natural Resources and Environment236 Le Van Sy1 WardTan Binh DistrictHo Chi Minh CityVietnam Agricultural Technology Research Center Hiroshima Prefectural Technology Research Institute6869HaraHachihonmatsuHigashihiroshimaHiroshima 739–0151Japan Program of Biotechnology Graduate School of Integrated Sciences for LifeHiroshima University1–3–1KagamiyamaHigashi-HiroshimaHiroshima 739–8530Japan Department of Civil and Environmental Engineering Graduate School of Advanced Science and EngineeringHiroshima University1–4–1KagamiyamaHigashi-HiroshimaHiroshima 739–8527Japan

Microbial electrosynthesis system (MES) is a promising method that can use carbon dioxide,which is a greenhouse gas,to produce methane which acts as an energy source,without using organic ***,this bioelectrical reduction reaction can proceed at a certain high applied voltage when coupled with water oxidation in the anode coated with metallic *** coupled with the oxidation of HS–to SO_(4)^(2-),methane production is thermodynamically more feasible,thus implying its production at a considerably lower applied *** this study,we demonstrated the possibility of electrotrophic methane production coupled with HS–oxidation in a cost-effective bioanode chamber in the MES without organic substrates at a low applied voltage of 0.2 *** addition,microbial community analyses of biomass enriched in the bioanode and biocathode were used to reveal the most probable pathway for methane production from HS–*** the bioanode,electroautotrophic SO_(4)^(2-)production accompanied with electron donation to the electrode is performed mainly by the following two steps:first,incomplete sulfide oxidation to sulfur cycle intermediates (SCI) is performed;then the produced SCI are disproportionated to HS^(–)and SO_(4)^(2-).In the biocathode,methane is produced mainly via H_(2)and acetate by electronaccepting syntrophic bacteria,homoacetogens,and acetoclastic ***,a new ecofriendly MES with biological H_(2)S removal is established.

关键词： Microbial electrosynthesis system Low applied voltage Organic substrates Methane production Sulfur oxidation

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Experimental and Simulation Analysis of Rca and Para-Wood Ash as Partial Substitutes for Nca and Cement in Recycled Aggregate Concrete

SSRN

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SSRN 2024年

作者： Sae-Long, Worathep Chompoorat, Thanakorn Limkatanyu, Suchart Damrongwiriyanupap, Nattapong Sukontasukkul, Piti Chub-Uppakarn, Tanan Thepumong, Thanakit Civil Engineering Program School of Engineering University of Phayao Phayao56000 Thailand Department of Civil and Environmental Engineering Faculty of Engineering Prince of Songkla University Songkhla90110 Thailand Construction and Building Materials Research Center Department of Civil Engineering King Mongkut’s University of Technology North Bangkok Bangkok10800 Thailand

Recycled concrete aggregate (RCA) is widely used as an alternative recycled material in engineering, while para-wood ash (PWA) is a natural agricultural waste product. To advance sustainable construction, it is crucial to thoroughly examine their impact on concrete’s mechanical properties to ensure safety in engineering applications. This paper conducts a series of experiments on recycled aggregate concrete (RAC) with PWA to investigate these replacement effects. RCA replaces natural coarse aggregate (NCA) at 0%, 50%, and 100%, while PWA substitutes cement at 0%, 10%, and 20%. The experiments include compression tests on mortar as well as compressive, tensile, and flexural tests on RAC, along with microstructure investigations. The results indicate a decrease in strength with higher proportions of RCA and PWA. Microstructure investigations were conducted via scanning electron microscopy with energy-dispersive X-ray analysis (SEM/EDX). SEM provides micro images of the testing specimens, while EDX offers insight into their chemical compositions. The EDX results reveal a direct correlation between the Ca/Si ratio and the strengths of mortar and RAC. Correlation studies between compressive strength-replacement parameters, tensile-compressive strength, and flexural-compressive strength demonstrate that the proposed equations accurately predict the experimental data with R2 values of 0.60 (for mortar), and 0.94, 0.95, and 0.71 (for RAC), respectively. Two numerical simulations validate the proposed model and showcase potential engineering applications. Finally, a 10% replacement of PWA for cement can reduce the embodied energy value (EEV) by approximately 9.46% for mortar mixed with PWA and around 10% for RAC mixed with RCA and PWA. © 2024, The Authors. All rights reserved.

关键词： Mortar

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