4 May 2026

Erosion Test Database Reassessment with Application to Engineered Soils

Abstract: This report presents a reevaluation of the soil erosion property relation-ships and a reanalysis of the data with a specific focus on compacted and engineered fill materials. Reinterpretation first centered on describing the parametric space of the database in which the models’ ability to predict critical shear stress and the erodibility coefficient parameter have the greatest uncertainty. Second, this work considered the smaller subset of the dataset with only engineered fill and compacted materials. However, considering only this subset was not found to reduce significantly the uncertainty in predictive capability. We recommend additional work to expand the dataset, focusing on materials in conditions more representative of the compacted and aged soils present on many flood control infrastructure projects.

4 May 2026

An Investigation of Causes of Inaccuracy of Infrared Radiation Cameras for Large-Scale Additive Manufacturing Applications

Abstract: In additive manufacturing, accurate temperature data are needed for both real-time feedback for print operators and understanding the thermomechanical behavior for prediction and part quality characterization. Through the collection of accurate temperature data, thermal models can be validated to predict process-induced properties of parts. Infrared radiation (IR) is used to determine the temperature of a surface. Because IR cameras measure thermal radiation from a distance without contact, they are safe to use in high-temperature environments like 3D printing. An investigation of reported temperature values for multiple cameras during one print showed a decreasing trend for cameras close to the printer’s heat sources, which was not reflective of the printing process, and a discrepancy of ±20°C when printing at 200°C across overlapping camera views. Two more prints were studied to determine whether this camera behavior was unique to that print and geometry. The analysis showed the same results across all three prints, with camera-reported values having inconsistencies for a single layer, a subset of layers, and the scale of the print. Multiple possibilities for the cameras’ variances were explored. The IR cameras were determined to require further calibration and experimentation before reported temperature values can be treated as physical temperature values.

29 Apr 2026

Bridge Load Rating for US Army Installations: Guidance

Abstract: This report summarizes Army policy and provides technical guidance for the load rating of vehicular and railroad bridges on US Army installations. These bridges must be load rated to determine and ensure their abilities to support the Army’s heavy military vehicles as well as all public-sector cars, trucks, or trains (in the case of railroad bridges). Installation bridge management and load ratings are accomplished under the Installation Management Command (IMCOM) Army Dams and Transportation Infrastructure Program (ADTIP), with technical support from the US Army Engineer Research and Development Center (ERDC).

29 Apr 2026

Deep Learning Approaches for Buried Object Detection in Infrared Imagery

Abstract: Artificial intelligence and machine learning techniques are increasingly utilized to detect buried objects in thermal infrared imagery. This task relies heavily on the quality and diversity of the training dataset, requiring datasets that capture variability present in real-world environments. Synthetic imagery offers a means to expose algorithms to a greater range of conditions than is often available in real-world data alone. This study evaluates the performance of three open-source object detection models—Faster Region-Based Convolutional Neural Network (R-CNN), You Only Look Once (YOLOv8), and Single Shot Multibox Detector—trained using real-world, synthetic, and hybrid datasets. Real-world imagery was collected from a single field site, while synthetic data were generated using the Virtual Environmental Simulation for Physics-Based Analysis software suite. Model performance was evaluated using Intersection over Union and confidence scores. Models trained exclusively on synthetic datasets with limited scene diversity, when tested on real-world imagery from the same location, produce high false-positive and false-negative rates. Detection performance im-proved significantly for Faster R-CNN and YOLOv8 when trained using a hybrid dataset combining real-world and synthetic data. Analysis of red-green-blue histograms revealed differences in pixel intensity distributions between real and synthetic imagery, indicating areas for improving synthetic data generation.

29 Apr 2026

Forward Operating Remote Camera for Engineering—Construction Assurance and Monitoring (FORCE-CAM), Generation 1

Abstract: This research delivered a first-generation, real-time construction monitoring capability, enabling visual situational awareness for off-site subject matter experts. The live-streamed and recorded data can be visualized from a remote computer desktop to aid in identifying non-conformance issues during active paving operations or during concrete damage assessment and repair operations. Experimentation on asphalt paving and skid-steer construction equipment using direct electro-optical and thermal sensors provided validation of the efficacy of this solution.

22 Apr 2026

Statistical Analysis of Large Format Additively Manufactured Polyethylene Terephthalate Glycol with 30% Carbon Fiber Tensile Data

Abstract: In large format additive manufacturing (LFAM), a keener understanding of the relationship between the manufacture method and material temperature dependency is needed for the production of large polymer parts. Statistical analyses supported by material properties and a meso-structural understanding of LFAM are applied to elucidate tensile data trends. The data from LFAM polyethylene terephthalate glycol with 30% carbon fiber (CF) (PETG CF30%) panels (diagonal, horizontal, and vertical in the x-y print plane) and injection-molded specimens tensile tested at six different testing temperatures (room temperature, 40 ◦C, 50 ◦C, 60 ◦C, 70 ◦C, and 80 ◦C) were used for statistical analyses. A standard deviation, a coefficient of variation, and a two-way and one-way analyses of variance (ANOVA) were conducted. The manufacturing method (44.2%) and temperature (47.4%) have a strong effect on the ultimate tensile strength, in which temperature (82.6%) dominates Young’s modulus. To explain the difference between the ultimate tensile strength of vertical, diagonal, and horizontal specimens at room temperature, a visual inspection of the specimen failure was conducted and the maximum stress at the crack tip was calculated analytically. The decreased strength in the diagonal specimens resulted from the reliance on interlaminar adhesion strength. Future work will consider the effect of the void space variation on tensile strength variance.

22 Apr 2026

Mesoscale Modeling and Parametric Studies of Concrete Materials

Abstract: This research focused on creating a mesoscale finite element model of concrete, treating it as a three-phase composite material composed of coarse aggregates, mortar, and the Interfacial Transition Zone (ITZ). The objective was to understand how these mesoscale structures influence the material's properties and responses under various loading conditions. The model simulated a normal-strength concrete with a compressive strength of approximately 27 MPa. The simulations included unconfined uniaxial compression, hydrostatic compression, uniaxial strain compression and triaxial compression, with the model's dimensions and boundary conditions mirroring those of laboratory tests on cylindrical specimens. The results from the simulations corresponded well with experimental data, validating the accuracy of the modeling method. Further parametric studies were conducted to examine how attributes like aggregate volume fraction and material properties impact the concrete's overall performance. This validated modeling provides a reliable pathway for optimizing concrete materials for specific uses, such as designing hardened structures for military applications. It also offers a method for estimating concrete properties when laboratory testing is limited or unavailable.

22 Apr 2026

Laboratory Performance Evaluation of Coarse Aggregates for Asphalt Concrete Mixtures

Abstract: An extensive laboratory evaluation was conducted to investigate the performance of coarse aggregates under different test methods. Test methods including the Los Angeles abrasion (LAA), sulfate soundness, Micro-Deval abrasion, aggregate crushing value, aggregate impact value, aggregate durability index, and aggregate slake durability were chosen to determine the aggregates’ resistance to abrasion, impact, crushing, and soundness. A total of twenty-five aggregate sources were included in the laboratory experiments, including seven different aggregate types (crushed gravel, gabbro, greywacke, granite, limestone, monzonite, and sandstone). The mineral composition of the aggregate sources was determined using X-ray diffraction (XRD) analyses. According to this study, the LAA test results were reasonable in screening out an aggregate source perceived as marginally resistant to abrasion. The sulfate soundness test results were ineffective in quantifying the quality of the different aggregate sources. Most alternative test methods identified similarly unacceptable aggregate sources, consisting mainly of aggregate types composed of carbonate minerals. Strong statistical correlations were not found among the aggregate test parameters. Recommendations were given to further investigate existing test requirements for the selection of coarse aggregates, particularly when using the sulfate soundness test method.

22 Apr 2026

Validation of the Swift and Quiet Airfield Assessment Device (SQUAAD)

Abstract: The need to rapidly determine the subsurface strength required to support various aircraft loading during contingency operations is critical to the success of tactical missions. Current Air Force Special Operations teams are required to perform this task using the dynamic cone penetrometer (DCP), a destructive test method that requires up to three personnel to operate, is time-consuming and representative of only a small area, requiring multiple tests to evaluate terrain suitable for airfield landing. An alternative, nondestructive methodology to capture the subsurface strength is the Swift and Quiet Airfield Assessment Device (SQUAAD). The purpose of the study presented in this report was to validate the SQUAAD to provide military personnel confidence in the operation and accuracy of the unit with respect to the legacy DCP device. A series of nine full-scale test sections were constructed at the US Army Engineer Research and Development Center’s indoor pavement testing facility. The test results indicate that the SQUAAD requires further testing and evaluation before it can replace the DCP.

22 Apr 2026

Transient Seepage Analysis for Flood Control Embankments

Abstract: Transient seepage analyses, which are becoming more common in practice, carry inherently more complexity compared with traditional saturated steady-state seepage analyses. The results of a four-year remote monitoring investigation were used to investigate common practices used in transient seepage analyses. Initial pore water pressure distributions were found to correspond to predicted infiltration distributions, which were less than typically assumed. The laboratory-measured drying soil water retention curve was found to provide an upper bound to field measurements. Field-measured soil water retention data were found to better correspond to a mean between the laboratory wetting and drying curves. Transient seepage and stability analyses showed that using a drying soil water retention curve resulted in lower factors of safety compared with using a wetting curve. However, a mean curve between the wetting and drying curves proved to be more accurate when compared with representative field measurements. Using unsaturated shear strengths along with conventional saturated shear strengths for levee embankments was found to minimally contribute to the stability factor of safety. Incorporating the findings from this investigation into a transient seepage analysis will help to improve the reliability of the results.