24 Nov 2025

Ice Demolition Techniques—Rapid Improved Ribbon Bridge Placement and Enemy Forces Denial: Using Traditional Military Explosives Under Ice

Abstract: As the United States military focuses on furthering their lethality across cold regions, developing new techniques for equipment usage is necessary. On 19 March 2025, the US Army Engineer Research and Development Center–Cold Regions Research and Engineering Laboratory (ERDC-CRREL) collaborated with the Army Engineers from the 50th Multi-Role Bridge Company (MRBC), 6th Brigade Engineer Battalion (BEB), and Sapper Leader Course (SLC) to determine whether explosives can be used for Improved Ribbon Bridge (IRB) placement in ice-laden environments. As the US Army adapts to meet the evolving threats from foreign adversaries, there is an increased tactical necessity for enhanced bridging capabilities in frozen terrain. Developing an expedient method of removing ice from these waterways and placing IRBs for easy crossing of heavy military equipment is essential. Through this experiment it was determined that the use of a 40 lb cratering charge primed with M152 boosters significantly fractures the ice cover expeditiously. However, the ice expulsion rate found in this experiment was insufficient for IRB deployment which requires 60% expulsion rate. Although the experiment fell short of IRB requirements, it proved to be an efficient and effective countermobility tool for units who use frozen water ways as avenues of approach.

24 Nov 2025

3D Printing Natural Materials for Nature-Inspired Infrastructure— A Beneficial Use Opportunity: Collaborative Research Workshop Synthesis

Abstract: Natural infrastructure—crucial for coastal resilience, flood risk management, and ecosystem services—confronts escalating challenges from rising seas, erosion, storms, and human impacts. Innovative approaches are needed to enhance infrastructure functionality and broaden social, economic, and environmental benefits. Traditional manufacturing constrains engineering creativity required for nature-inspired infrastructure (NII). Additive manufacturing, or 3D printing (3DP), could revolutionize the design and functionality of NII. However, existing capability gaps hinder the effective transition of these technologies from conceptualization to implementation. Our workshop explored NII-3DP structures using natural materials, aligning with Engineering With Nature® (EWN®) principles and US Army Corps of Engineers infrastructure goals. Discussion included engineering solutions to provide social, recreational, environmental, and economic benefits, including flood risk reduction, wave energy dissipation, nutrient sequestration, and habitat enhancement. The participants sought to understand material selection and optimize morphologies to ensure the successful biocompatibility of nature-based habitats. By using locally sourced, biocompatible materials and drawing inspiration from nature, these technologies offer a means to enhance habitat function and improve aesthetics for communities. A timely opportunity exists to reshape the perception of locally available materials, such as sediment, by presenting dredged material as an environmentally and economically beneficial use asset and resource for 3DP feedstocks.

10 Nov 2025

Spatial Analyses of Atmospheric Rivers in the Willamette River Basin of Oregon: Literature Review and Atmospheric River

Abstract: This technical note summarizes the literature review and atmospheric river (AR) detection technique data collection and initial processing activities that were performed in preparation to spatially storm type (i.e., categorize) AR extreme storm events in Oregon’s Willamette River Basin (WRB). Storm typing is performed to develop a homogeneous extreme event dataset for precipitation-frequency analyses, whose products are used to support business line (e.g., Dam and Levee Safety and Flood Risk Management) activities of the US Army Corps of Engineers (USACE). Twenty-three Atmospheric River Tracking Method Intercomparison Project (ARTMIP) Tier 1 data catalogs were collected from the US National Science Foundation’s National Center for Atmospheric Research Climate Data Gateway (Rutz et al. 2019). Each catalog models the binary presence or absence of an AR on a gridded basis, globally, at a three-hour time step from 1980 to 2016. Any ARTMIP Tier 1 catalog could effectively be selected and applied to segment AR extreme storm events for a given area by intersecting it with a prescribed precipitation dataset. However, each catalog characterizes the presence or absence of ARs differently. Hence, there exists uncertainty regarding which ARTMIP Tier 1 catalogs to select for a given practical application. This technical note addresses the uncertainty associated with ARTMIP Tier 1 catalog choice by generalizing model selection (i.e., which ARTMIP Tier 1 methods to use). Monthly climatological AR frequency was calculated throughout the WRB for each of the 23 ARTMIP Tier 1 data catalogs. Thirteen of the AR identification and tracking methods that together consistently calculated climatological AR frequency throughout the WRB were selected to form an ensemble subset. The 13-member ensemble could be used to develop AR storm type (Ralph et al. 2019) annual and seasonal maxima datasets to compute areal-precipitation-frequency estimates for the contributing drainage areas of dams in the WRB that are operated and maintained by USACE.

5 Nov 2025

Physical Modeling of Filling and Emptying (F&E) Systems of Proposed 1,200 ft Chambers at Locks 22 and 25: Hydraulic Model Investigation

Abstract: The US Army Corps of Engineers (USACE) is considering navigation improvements for several projects to meet predicted increases in tow traffic at the Lock and Dam 22 and Lock and Dam 25 sites in the Mississippi river. Some of these improvements include the addition or replacement of the navigation lock at the site. The following document contains the laboratory model investigations of the lock filling and emptying (F&E) system for additions at the sites. This report provides the results of research testing under the Navigation and Ecosystem Sustainability Program (NESP). The design guidance includes culvert geometry, port size, location, and spacing. Guidance for the lock chamber performance, based on acceptable filling and emptying operations is also included. The results show that the original design is a feasible design based on the hydraulic performance of the system as a result of the experimental tests. Further discussions with the St. Louis District (CEMVS) arrived at a new culvert to port transition design that was more in line with the existing geometry at Lock and Dam 25. The new design and port spacing configuration were agreed by CEMVS and ERDC to not have significant impact on hawser forces or the overall chamber performance.

4 Nov 2025

Preliminary Evaluation of Selected Expeditionary Shelter Systems in a Subarctic Environment: Phases I and II of Cold Weather Testing

Abstract: The warming of high latitude regions is causing geopolitical concerns and spurring increased human presence across the Arctic. Potentially, these situations require only a short-term occupation necessitating tested and developed expedient infrastructure. Operating requirements for high latitude conditions are vastly divergent from temperate locations. Shelters must be able to provide habitable conditions at temperature down to −60°F, withstand 100 mph wind speeds, and support 25 lb/ft2 of snow load. Although great advances have been made in providing efficient and comfortable Arctic infrastructure since the onset of the Cold War, significant work remains to further increase efficiencies and adapt to changing weather parameters. To address infrastructure technology gaps, the US Army Corps of Engineers–Engineering Research and Development Center (USACE-ERDC) established the Arctic Infrastructure Research Group (AIRG). Over two phases of investigation, the AIRG evaluated three selected expeditionary shelter systems at its Arctic Infrastructure Research Center (AIRC) in Fairbanks, Alaska during the winters of 2020–2021 (Phase I) and 2021–2022 (Phase II).

4 Nov 2025

High-Frequency Electromagnetic Induction for Oil Detection in Freshwater Ice Conditions

Abstract: High-frequency electromagnetic induction (HFEMI) effectively detects objects and materials in environments where visual detection may not be possible. Existing HFEMI sensor designs are for detection of improvised explosive devices and unexploded ordinances. This project applied this technology to oil spill detection and response applications. Because of the significant ice cover experienced in the Great Lakes Regions, the US Coast Guard requires fast and effective means to detect and characterize oil spills in and under layers of ice. HFEMI technology was adapted and evaluated for its ability to detect submerged oil of various types under several conditions of ice. The signal response of the sensor shows this technology is effective at detecting different types and volumes of oil in thin to moderate ice conditions, but could be improved to expand the distance of detection for thicker ice coverage.

4 Nov 2025

Airfield Assessments to Identify Improvements in Support of Arctic Military Operations: Arctic Airfields Assessment

Abstract: This report examines current airfield capabilities in Alaska and Greenland as they pertain to the strategic priorities of the Northern Aerospace Defense Command (NORAD) and US Northern Command (NORTHCOM) in support of needs identified in the 2024 DoD’s Arctic Strategy. With increasing activity and competition in the circumpolar region, airfields in Alaska and Greenland play a vital role in enabling homeland defense, supporting domain awareness needs, and enabling rapid response operations. This report highlights key airfields across Alaska and Greenland, focusing on their current readiness to support NORAD-assigned airframes such as the C-17, C-130, F-15, F-16, F-22, F-35A, KC-10, KC-135 and KC-46A. It assesses currently available infrastructure, operational resilience, airfield suitability and current condition, weather considerations, and logistics sustainment. Gaps in infrastructure readiness and logistical necessities for different airframes are identified. Recommendations are provided to bolster airfield operational capabilities as they pertain to the NORAD mission, and to ensure Arctic basing remains a credible enabler of NORTHCOM’s mission to defend the US and deter threats across the circumpolar region.

30 Oct 2025

Thermomechanical Material Characterization of Polyethylene Terephthalate Glycol Carbon Fiber 30% for Large-Format Additive Manufacturing of Polymer Structures

Abstract: Large-format additive manufacturing (LFAM) is used to print large-scale polymer structures. An understanding of the thermal and mechanical properties of polymers suitable for large-scale extrusion is needed for de-sign and production capabilities. An in-house-built LFAM printer was used to print polyethylene terephthalate glycol with 30% short carbon fiber (PETG CF30%) samples for thermomechanical characterization. Thermogravimetric analysis confirmed the samples had 30% carbon fiber by weight. X-ray microscopy and porosity studies found 25% porosity for undried material and 1.63% porosity for dry material. Differential scanning calorimetry showed a glass transition temperature (Tg) of 66°C, while dynamic mechanical analysis found Tg to be 82°C. The rheology indicated that PETG CF30% is a good printing material at 220°C–250°C. Bending experiments showed an average of 48.5 megapascals (MPa) for flexural strength, while tensile experiments found an average tensile strength of 25.0 MPa at room temperature. Comparison with the literature demonstrated that the 3D-printed PETG CF30% had a high Young’s modulus and was of similar tensile strength. For design purposes, prints from LFAM should be considered from a bead–layer–part standpoint. For testing purposes, both material choice and print parameters should be considered, especially when considering large layer heights.

30 Oct 2025

Full-Scale Evaluation of Multi-Axial, Multi-Aperture Shape Geogrids in Flexible Pavement Applications

Abstract: The US Army Engineer Research and Development Center (ERDC) con-structed a full-scale pavement test section to evaluate the performance of three recently developed multi-axial, multi-aperture shape geogrids, referred to as HX5.5, NX750, and NX-Dev, in asphalt-surfaced highway applications. The test section consisted of a 4.2 in. thick and a 3.8 in. thick hot-mix asphalt layer placed over a 6 in. thick and 4 in. thick crushed aggregate layer, respectively. Underlying the crushed aggregate layer was a 2 ft thick clay subgrade that had a 6% California Bearing Ratio. Simulated truck traffic was applied using ERDC’s heavy vehicle simulator–transportation with a dual-wheel tandem axle truck gear. Rutting performance and instrumentation response data were monitored at multiple traffic intervals. Observed rutting in the geogrid test items was approximately one-third of that in the unstabilized item, in which was a meaningful performance improvement. Instrumentation response data indicated that the geogrid inclusion pro-vided a stiffening effect that altered the anticipated pavement response. An analytical investigation showed that traditional layered elastic analysis techniques did not adequately describe the pavement response with geogrid inclusion. A robust model that included material nonlinearity and a geogrid interface model provided a closer approximation to the measured subsurface response.

29 Oct 2025

Beneficial Use of Contaminated Sediments: A Review of Technical, Policy, and Regulatory Needs

Abstract: This special report summarizes key results from the March 2024 Sediment Management Working Group (SMWG) Contaminated Sediment Beneficial Use Workshop sponsored by US Army Engineer Research and Development Center’s (ERDC’s) Advanced Materials and Substances of Emerging Environmental Concern (AMSEEC) center, a multilaboratory research collaborative reviewing solutions to environmental challenges, and the Dredging Operations Environmental Research (DOER) Program, the navigational dredging research arm of ERDC. The workshop focused on potential avenues for treatment and management of contaminated sediments to support expanded beneficial use (BU) opportunities. AMSEEC, with support from DOER, sponsored four pilot studies to advance the technical aspects of the workshop program and partnered with the SMWG, an industry consortium, to organize the workshop in Washington, DC. The workshop was attended by more than 75 practitioners and relevant stakeholders to review these pilot studies and the challenges of advancing treatment and management of contaminated sediment to support BU. This special report summarizes and prioritizes technical, regulatory, and policy needs to enable expanded BU opportunities for contaminated sediments.