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Deterioration Prediction and Optimal Repair Timing Assessment for RC Abutments in Tidal River Environments
No full textReinforced concrete (RC) abutments constructed in tidal rivers are periodically exposed to saltwater due to tidal fluctuations, which can lead to rebar corrosion and a decline in structural performance. To maintain such infrastructure more efficiently and cost-effectively, high-resolution simulations in both time and space can help predict the timing of performance degradation with greater accuracy, enabling optimal repair and reinforcement scheduling. Achieving higher accuracy in these simulations requires appropriate modelling of continuous environmental variations, such as tidal fluctuations, temperature, and humidity. This study focuses on RC abutments located in tidal zones and examines a modelling approach to represent environmental conditions at different heights. During low tide, the abutment is exposed to air and undergoes drying, while at high tide, it is submerged in seawater. The penetration rate of chloride ions differs depending on moisture conditions: in drier areas with prolonged air exposure, advection plays a dominant role, whereas in continuously submerged regions, diffusion governs chloride transport. Considering these effects, a method was developed to determine environmental actions based on time increments used in simulations. Furthermore, future simulations based on this modelling approach were conducted to evaluate the timing and extent of rebar corrosion at different locations within the abutment. The results provide insight into how structural performance deteriorates over time, contributing to the development of optimised maintenance strategies for RC structures in tidal environments
Relationship between Water Contents and Electrical Conductivity in Concrete
No full textThis study investigates the relationship between moisture absorption and electrical conductivity in concrete, aiming to evaluate the feasibility of using electrical impedance as a non-destructive indicator of moisture transport behaviour. Concrete specimens with varying water-to-cement (w/c) ratios were prepared and conditioned for 150 days under controlled air-drying conditions. Moisture absorption tests were conducted in accordance with ASTM C1585-20, and both weight change and impedance were measured over time. Impedance data were collected across a wide frequency range (10 Hz to 1 MHz) using a two-point measurement configuration, and direct current (DC) electrical conductivity was derived through nonlinear regression analysis based on Jonscher’s power law. The results demonstrate a strong correlation between absorbed moisture content and electrical conductivity, with higher w/c ratios yielding increased conductivity due to greater pore connectivity. Furthermore, the data reveal a linear relationship between weight gain and conductivity, suggesting that continuous pores within concrete serve as common pathways for both moisture and ionic transport. Although this study did not confirm the saturation state of specimens or isolate the influence of closed pores, the observed trends are consistent with prior findings. These results highlight the potential of electrical conductivity as a practical, non-destructive tool for assessing moisture-related deterioration in concrete structures
MULTI-MODAL SPECTRAL FUSION FOUNDATION MODEL
No full textFarms run on data, but our sensors rarely agree: optical is cloud-limited, radar sees structure but not color, UAVs arrive on their own schedule, and resolutions vary by field and season. We introduce a modular multisensor fusion backbone that turns heterogeneous streams (e.g., Sentinel-2, Sentinel-1, Planet/UAV) into a single, field-centric representation designed for agronomic decision-making. The system leverages strong pretrained encoders per modality and a compact cross-modal exchange layer to integrate signals while remaining resilient to gaps (missing sensors, clouds, irregular cadence) and shifts in scale. Training relies on broadly applicable self-supervised objectives and large unlabeled archives, minimizing label demands. In preliminary studies, the fused embedding is stable, subset-robust, and deployable from plot to region with low latency. Ongoing work evaluates temporal extensions for phenology and within-season forecasting.
Potential impact in digital agriculture: early abiotic stress alerts and irrigation guidance; yield nowcasting/forecasting; nitrogen management support; emergence & gap mapping; storm/lodging and disaster impact assessment; disease/pest early warning; indicators for carbon and water accounting
MgO boards – the tension between innovation and standardisation
No full textNational and international test standards are critical to how we use and design cementitious materials. However, there are occasions when products, such as magnesium oxychloride boards, do not fall within existing harmonised standards. Technical Assessment Bodies do provide a way of allowing the introduction of new materials via European Technical Assessment or British Board of Agrément certification. Such certification should provide confidence to insurance bodies and building owners in the absence of a national standard, which can take many years to emerge. This paper discusses the fundamental science and testing of MOC boards and the discovery of startling difference in performance of products with such certification. Some products were found to fail in less than two weeks of durability testing while others did not demonstrate any signs of distress despite all products being openly available for use within the UK and EU
Culvert Replacement in Karst Topography
No full textSouthern Indiana’s unique karst terrain presents both fascinating natural features and complex engineering challenges. This presentation explores the preliminary design and field reconnaissance measures of an active infrastructure project. The session will trace the project’s development from initial planning through Stage 1 design and field observation, highlighting how the team adapted standard practices to this distinctive geologic setting. Using pipe inspection footage, INDOT archive plans, and photos, we will demonstrate how the design team is addressing culverts discharging directly into karst features via chimney systems under the road. We will also discuss preliminary water quality treatment options being considered to protect sensitive groundwater pathways. This session is ideal for professionals interested in geology-informed design, stormwater engineering, environmental protection, and infrastructure resilienc
Empowering Indiana through Orthoimagery, LiDAR, and Geospatial Resources
No full textThe Indiana Geographic Information Office invites you to explore the state’s Imagery and Elevation Program, spotlighting the many ways users can access high-quality, authoritative orthoimagery and LiDAR data via both CAD and GIS platforms. This session will provide a historical overview of the program’s development and recent updates to the data collection cycle for 2025-2028, in addition to how to access the data through various platforms.
We’ll also showcase the growing library or geospatial data openly available through IndianaMap. From web mapping and Field Maps to various ArcGIS Online tools, IndianaMap empowers curious GIS users across the state to create Community accounts and engage in entry-level GIS activities with ease
Editors’ Introduction to the Special Issue on Hip-Hop Pedagogy for Students with Disabilities (Side A)
No full textThe co-editors of the Journal of the Arts and Special Education (JASE) introduce the special issue by outlining the impetus for its development. The editorial concludes with a description of why Hip-Hop is a timely and relevant topic for JASE and it’s readership
Reference at a remote field station: a case study of ecology, environmental science and geology fieldwork at an embedded library
No full textPurpose Field station libraries, particularly those serving biological and marine research stations, represent a unique but understudied class of special libraries. This case study investigates reference services at the remote University of Michigan Biological Station (UMBS) to provide a baseline assessment of how such services support the information needs related to research in ecology, geology and environmental science.
Design/methodology/approach The study recorded, coded and analyzed 209 reference transactions from the 2022 and 2023 summer sessions, revealing trends in patron inquiries and the role of the reference desk. Further, the case study examined the organizational structure, community interaction and mission of the field station library.
Findings The study concludes that UMBS\u27s field station library functions as a form of embedded librarianship, characterized by shared administration between the main campus library and the field station, deep integration into the community and subject matter expertise in relevant scientific disciplines. The in-person reference desk is a well-utilized library service that has documented increased use in recent years, contrary to national trends.
Originality/value This is the first time reference services at a remote field research station have been examined. It will inform field station librarians and administrators, as well as main campus ecology, geology and environmental science subject specialist librarians in working with the needs of their community. This investigation lays the groundwork for a broader survey to enhance understanding and development of field station libraries as a distinct type of special library. Understanding the field station library as a type of embedded library will assist in assessing the library as well as improving services and patron experience
Flood Prediction with Sentinel-1 Synthetic Aperture Radar from Hurricane Helene
No full textFloods are the most common natural disaster globally, causing thousands of deaths every year. Timely and accurate flood forecasts are crucial for developing early warning systems, evacuation plans, and effective strategies to enhance community resilience. Soil moisture is an important parameter in flood forecasting. Unfortunately, existing soil moisture sensor networks and optical remote sensing–based techniques for soil moisture estimation lack the spatial resolution needed for accurate flood forecasting. This study presents an approach for flood prediction using Sentinel-1 C-band synthetic aperture radar (SAR) data. SAR offers high spatial resolution and operates day and night under all weather conditions, making it advantageous for flood modeling. Furthermore, Sentinel-1’ s six-day revisit cycle allows for relatively continuous soil moisture monitoring, which is essential for flash flood modeling. This study uses Hurricane Helene, which impacted the southeastern United States between September 24 and September 27, 2024, as a case study. Flood analyses are performed in parts of North Carolina, Tennessee, and Georgia. Ten USGS streamgages were selected, and flood extents around each streamgage are mapped using stream stage data from the USGS National Water Information System (NWIS) mapper. For each streamgage, Sentinel-1 images ranging from two weeks before to two weeks after the storm were gathered using the Alaska Satellite Facility’s Vertex Data Search. A support vector machine (SVM) classifier is trained to relate SAR backscatter parameters to flooding. The model accuracy was improved by also including precipitation rate, land use/land cover, and elevation data as inputs. This approach is promising for improving flood prediction accuracy and spatial resolution, especially in areas with limited ground-based soil moisture sensor networks
