11 Aug 2026

AFM Analysis of Rejuvenated Graphene Nanoplatelets for Nanoscale Reinforcement and Microwave-Induced Healing in Asphalt Binders

Abstract: Understanding nanoscale mechanisms governing reinforcement and healing in asphalt binders is essential for developing durable pavements. This study investigates graphene nanoplatelets (GnP) and rejuvenator-infused graphene (GnP-Rej) in a PG 67–22 binder using PF-QNM atomic force microscopy under unaged, PAV-aged, and microwave-treated conditions. GnP refined binder morphology, reducing surface roughness from ~2.1 nm to ~1.44 nm at 0.24 wt% and increasing stiffness through molecular confinement, with saturation beyond ~0.1 wt% due to agglomeration. Aging increased peri- and para-phase modulus by ~68% and ~61%, respectively, while GnP and GnP-Rej mitigated these effects. GnP-Rej exhibited dual-function behavior, enhancing local compliance and interfacial mobility. Microwave activation increased adhesion by up to ~51% without significant modulus change. The adhesion-based healing index confirmed consistent nanoscale recovery, with maximum healing observed at 0.24 wt% GnP-Rej. These results indicate that healing is governed by adhesion-controlled nanoscale recovery and provide mechanistic insight into the relationship between nanoscale behavior and improved asphalt performance.

3 Aug 2026

An Innovative Approach of Vibration Testing of Concrete Structure Using Performance Based Evaluation Techniques

Abstract: Many of our nation’s critical water resource infrastructures have already surpassed their intended design lives. Therefore, there is a critical need to develop assessment procedures that will transform dam operations and stabilization mechanisms that can extend the service life of these vital structures. These actions are crucial for ensuring safe and secure public services. Performance-based testing using a cold gas thruster (CGT) is a new and innovative nondestructive testing technique that is being implemented to better assess critical infrastructure. The CGT is an instrument that delivers a high-magnitude, short-duration impulse load that produces an impulse response in the structure. Using these dynamic responses, the structure’s behavioral response and key performance indicators can be determined. Furthermore, a high-fidelity numerical model that accurately predicts behaviors can be developed with the use of these dynamic responses.

20 Jul 2026

ACE-Mat: Medium- and Full-Scale Testing over Weak Soils

Abstract: The US Army lacks the capability to rapidly repair and upgrade damaged roads along mobility corridors in contested, complex environments. Damaged low-volume roads are often encountered in military operational scenarios for transporting troops, supplies, equipment, and materials. Airfield matting is a unique solution for rapid construction of airfields in austere environments. The study presented in this report used medium-scale testing to evaluate the performance of the US Army Corps of Engineers’ ACE-Mat over varying soil strengths for rapid road repair scenarios. Tests were run using cyclic plate loading, simulating the load and tire pressure of a common bridge transporter military vehicle. Tests were completed on the mat and directly on the soil for comparison. An additional full-scale field test was completed to validate the medium-scale testing. The results of all tests indicate that the ACE-Mat provides exceptional performance improvement of weak soils.

20 Jul 2026

Quantifying Early-Age Oxidation to Inform Performance-Based Specifications for Surface Treatments on Airfield Asphalt Pavements

Abstract: This report details a laboratory evaluation, including 1,024 tests, where progression of early-age oxidation was monitored in three airfield asphalt pavements during the first year after construction. The motivation was to provide a foundational understanding of early-age oxidation in airfield asphalt pavements to inform properties of interest to understand optimal timing for applying surface treatments. Testing evaluated near-surface oxidation using traditional methods found in literature (i.e., extracted and recovered asphalt binder properties) and a more novel approach using mixture properties related to distresses due to oxidation (i.e., cracking) that are believed to have greater potential for specifying surface treatment products. Nearly all results indicated meaningful oxidation occurs within the first 12 or 18 months after construction; however, this oxidation is limited to the top 6.3 mm of the pavement surface. In terms of conventional performance grading (PG) assessments, the degree of aging equated to one to two high PG increases in the near-surface as early as 8 months. Bending beam rheometer (BBR) mix beam testing generally agreed with other mixture and binder tests, providing confidence in its validity. From this, m-value emerged as the recommended parameter for analyzing oxidative aging and surface treatment products moving forward.

7 Jul 2026

FIMOFs: Fiber-Integrated Metal–Organic Frameworks through Electrospinning

Abstract: Green synthesis plays a crucial role in advancing sustainability within materials science. This study explores the integration of metal–organic frameworks (MOFs), obtained through green synthesis, using an electrospinning post-processing technique to develop MOF-based composite materials. The resulting novel multifunctional composites demonstrate enhanced stability and functionality, compared to their control counterparts. The integration of four types of MOFs into an electrospun fiber network was investigated using a specific polymer solution. Characterization and preliminary adsorption studies were conducted to elucidate the chemistry, morphology, and adsorptive capabilities of the resulting MOF composites. Electrospinning MOFs into polymer fibers improved their stability and dye removal capabilities. More specifically, optimization of MOF-to-polymer ratios and processing conditions yielded composites that are thermally stable, with modified surface area and porosity. Post-processing MOFs resulted in a fiber diameter increase of 44 and 109%, enhancing the composites by providing more MOF active sites and improved mechanical strength. Zirconium-based post-processed MOFs demonstrated superior dye removal, different from the copper-based dyes. Electrospinning technology has demonstrated significant potential in the fabrication of high-performance multifunctional MOF composites. This has helped to create advanced sustainable composites with tailored properties, paving the way for more targeted and efficient applications. The applications of these composites show promise for military engineering where durable, light weight, and multifunctional materials are critical in contributing to improved performance, operational efficiency, and safety.

6 Jul 2026

Rapid Assessment of Airfield Pavements

Abstract: The US Navy identified pavement assessment shortfalls under its Facilities Shore Readiness (FSR) program. Two assessment needs were related to (1) rapidly assessing the condition of existing concrete structures such as roads, parking lots, and airfields of port facilities and (2) using nondestructive devices to determine pavement thickness. The project described in this report evaluated the efficacy of two technologies: WayLink Systems Corporation’s automated pavement condition surveys and the MIRA Shear Wave 3D Tomographer, which identify real-time pavement surface conditions and pavement thicknesses, respectively. These commercial off-the-shelf systems offer great potential value, especially when historical construction and maintenance data are unavailable. Test data for this project were collected on asphalt and concrete runways, taxiways, aprons, parking lots, and roads. The overall results indicated that automated pavement surveys are not currently ready for full implementation on airfield pavements. The MIRA tomographer had success in estimating pavement thickness and is recommended for implementation in pavement evaluations.

1 Jul 2026

Development of High-Performance Cold Mix Asphalt for Asphalt Patching

Abstract: Cold mix asphalt (CMA) is commonly used to perform small asphalt patching repairs. It is readily available even when hot mix asphalt (HMA) is not due to distance from a plant or cold weather; it is convenient and can be kept on hand; and it can be used at ambient temperatures. Unfortunately, these advantages are generally offset by marginal performance, especially under heavy loads and at quick return-to-traffic times. For military airfields in particular, both logistical factors and adequate performance are critically important; typical CMAs cannot deliver both, and HMA is not always readily available. Consequently, the objective of this project was to develop a new high-performance CMA that combines convenience and logistical advantages of conventional CMA with the performance expected from HMA. This objective was met using an asphalt-modified polyurethane binder to design cold mix that far outperforms conventional CMA and rivals (exceeds, in some cases) HMA performance, based on both laboratory and full-scale field testing. This two-part material can be field mixed without special mixing equipment; once cured, it is highly elastic, exhibits little temperature sensitivity, and can withstand up to 300 passes of F-15E aircraft traffic with a 3 hr return-to-traffic time (1 in. rutting threshold).

26 Jun 2026

Examination of Analytical Shear Stress Predictions for Coastal Dune Evolution

Abstract: Existing process-based models for simulating coastal foredune evolution largely use the same analytical approach for estimating wind-induced surface shear stress distributions over spatially variable topography. Originally developed for smooth, low-sloping hills, these analytical models face significant limitations when the topography of interest exhibits large height-to-length ratios and/or steep, localized features. In this work, we utilize computational fluid dynamics (CFD) to examine the error trends of a commonly used analytical shear stress model for a series of idealized two-dimensional dune profiles. It is observed that the prediction error of the analytical model increases compared to the CFD simulations for increasing height-to-length ratio and localized slope values. Furthermore, we explore two data-driven methodologies for generating alternative shear stress prediction models, namely, symbolic regression and linear, projection-based, non-intrusive reduced-order modeling. These alternative modeling strategies demonstrate reduced overall error but still suffer in their generalizability to broader sets of dune profiles outside of the training data. Finally, the impact of these improvements on aeolian sediment transport fluxes is examined to demonstrate that even modest improvements to the shear stress prediction can have significant impacts on dune evolution simulations over engineering-relevant timescales.

7 May 2026

Surface Oxide Removal in Preparation for Controlled Liquid Metal Embrittlement

Abstract: During liquid metal embrittlement a liquid metal infiltrates grain boundaries of a compatible solid metal, interrupting the inter-grain bonds and weakening the metal. Ongoing research has proposed that this effect may be used to perform additive/subtractive hybrid machining to fabricate replacement components, using relatively simple equipment and low material and instrument costs. The gallium/aluminum pairing is of particular interest due to the usage of aluminum in a wide variety of structural and aerospace applications coupled with gallium’s nontoxicity and melting point just above room temperature, which facilitates storage and transport. To activate aluminum to gallium infiltration, the surface oxide formed on aluminum in atmosphere must first be removed simultaneously with a significant amount of bulk metal to promote flow control of the liquid metal. Three targeted techniques for oxide removal were tested and compared, specifically mechanical abrasion, chemical etching, and laser ablation. Mechanical abrasion is simple to implement but lower precision. Chemical etching requires significant prep work and cleanup but could operate on entire sheets of substrate simultaneously with proper masking. Although laser ablation requires the most complex instrumentation, it requires minimal prep work and provides the greatest precision, making it ideal for the manufacturing application under development here.

7 May 2026

Tribological Properties of Synthetic and Biosourced Lubricants Enhanced by Graphene and Its Derivatives: A Review

Abstract: This review explores the tribological properties of biosourced lubricants (biolubricants) enhanced by graphene (Gr) and its derivatives and hybrids. Friction and wear at mechanical interfaces are the primary causes of energy loss and machinery degradation, necessitating effective lubrication strategies. Traditional lubricants derived from mineral oils present environmental challenges, leading to an increased interest in biolubricants derived from plant oils and animal fats. Biolubricants offer high biodegradability, renewability, and low toxicity, positioning them as ecofriendly alternatives. This work extensively reviews the role of Gr-based nanoadditives in enhancing the lubrication properties of biolubricants. Gr with its exceptional physicomechanical properties has shown promise in reducing friction and wear. The review covers various Gr derivatives, including Gr oxide (GO) and reduced Gr oxide (r-GO), and their performance as lubrication additives. The discussion extends to Gr hybrids with metals, polymers, and other 2D materials, highlighting their synergistic effects on the tribological performance. The mechanisms through which these additives enhance lubrication, such as the formation of protective films and improved interactions between lubricants and tribopairs, are examined. Emphasis is placed on the environmental benefits and potential performance improvements of Gr-based biolubricants. Finally, by analyzing current research and technological trends, the paper outlines future prospects for optimizing lubricant formulations with Gr-based nanoadditives, aiming for more sustainable and efficient tribological applications.