20 Oct 2025

Tensile Strength of Native Boreal Forest Plant Species

Abstract: Plant roots influence the engineering properties of soil, such as erodibility and strength. Plant roots’ contribution to soil shear strength is of particular importance in Arctic and subarctic environments where the shallow subsurface experiences a decrease in shear strength due to permafrost thaw, subsidence, and wildfires. This paper presents the testing method, sample collection and specimen preparation, and tensile strength testing results for laboratory- and greenhouse-grown boreal forest plants to compare root tensile strengths among plant species and functional groups, including deciduous shrubs and trees, evergreen trees, forbs, graminoids, and grasses using a universal testing machine and a modified triaxial device. The results illustrate that root tensile strength increases as root diameter decreases (as a power function). The root diameters successfully tested ranged from 0.063 mm (grasses) to 8.72 mm (deciduous shrubs) across all functional groups. When compared across functional groups and root diameters for each species, grass roots exhibited the highest tensile strength for root diameters less than 0.8 mm, deciduous tree roots displayed the largest tensile strength for root diameters greater than 0.8 mm, and forbs were consistently the weakest, supporting the conclusion that a diverse spread of functional groups is most effective for slope stabilization.

2 Oct 2025

Innovative Existing Building Commissioning (EBCx) Assessment Training Tools

Abstract: In an effort to develop active and engaging online training experiences that effectively simulate hands-on lessons and provide an experience equivalent to on-site visits, researchers at the Construction Engineering Research Laboratory (CERL) developed a series of immersive web-based training tools that support virtual learning. This report discusses the role of active learning, the need for advanced training tools, and describes the CERL effort to develop training tools. It also provides feedback on the experiences and effectiveness of various platforms that were used to develop these tools.

1 Oct 2025

US Army Water Reuse: 2023 Survey of Wastewater Reuse at US Army Installations

Abstract: The US Army Corps of Engineers, Engineer Research and Development Center, Construction Engineering Research Laboratory (USACE ERDC-CERL), partnered with the US Army Material Command (HQAMC G4) to collect information on water use and wastewater to understand water re-use at the installation level by distributing a water reuse questionnaire. From May to September 2023, ERDC-CERL compiled the 98 responses received from all Army installations and established the following baseline data for water reuse: the US Army produces 35.9 million gallons per day (MGD) of effluent, 30.4 MGD of which receives a minimum of secondary treatment making it potentially eligible for reuse, however the US Army currently only reuses 4.51 MGD. Current reuse practices save the Army up-wards of $751,849 every month in potable water cost offsets; however, the Army could potentially save approximately $4.3 million every month if they expanded their water reuse to its current full capacity (including re-use of effluent receiving secondary or tertiary treatment). This project will be foundational for continual studies of water reuse in the Army. It will aid in creating installation energy and water plans (IEWPs), in developing a proposed geospatial dashboard tool, and in further water reuse projects with other Department of Defense departments.

23 Sep 2025

Topology Optimization for 3D Printing-Driven Anisotropic Components Accounting for Stress and Displacement Constraints

Abstract: Concrete 3D printing produces a layered macrostructure with different properties in three orthogonal directions, while new techniques allow printing at different orientations. Can printing with spatially variable layer-to-layer interface orientations produce lighter structures while stress and displacement limits are met? This study establishes the connection between experimentally measured properties of printed concrete samples and parameters of orthotropic elasticity and orthotropic yielding. Building upon this connection, a topology optimization framework is built that minimizes weight with respect to the material distribution and spatially variable layer orientation, while simultaneously addressing stress and displacement constraints. This framework is implemented via the Augmented Lagrangian approach and the Method of Moving Asymptotes, and sensitivities are calculated using the adjoint method to reduce computational cost. To expedite convergence without constraint violations, the concept of offset tolerances is introduced and by introducing a cubic term in the displacement constraints accelerating it at large constraint violations and introducing a density-weighted change norm for the orientation angles to eliminate the effect of inconsequential orientation variations in regions of negligible density. This framework enables investigation of fixed vs. variable orientation, tension-compression asymmetry vs. symmetry in achieving low weights, and the relative effect of stress vs. displacement constraints in minimizing weight.

23 Sep 2025

Loch Raven Veterans Administration Medical Center: Historic Context and National Register Evaluation

Abstract: This project was undertaken to provide the US Department of Veterans Affairs, Construction and Facilities Management Office, with a National Historic Preservation Act, Section 110, evaluation of the Loch Raven Veterans Administration (VA) Medical Center. The approximately 14.85-acre medical center is located in Baltimore, Maryland. The Construction and Facilities Management Office tasked the US Army Engineer Research and Development Center, Construction Engineering Research Laboratory (ERDC-CERL) with inventorying and assessing the Loch Raven VA Medical Center for eligibility to the National Register of Historic Places through the creation of a historic context, a description of current conditions, and an analysis of those elements using the appropriate National Register bulletins. The authors recommend that the Loch Raven VA Medical Center not be eligible for the National Register of Historic Places due to a lack of architectural and landscape integrity of the complex; however, it is recommended that Building 1 be reevaluated for the National Register when it turns 50 years of age in 2046.

17 Sep 2025

Spring House, 666 Front Street, Lahaina, Hawaiʻi: Historic American Buildings Surveys HI-676

Abstract: The US Congress codified the National Historic Preservation Act of 1966 (NHPA), the nation’s most effective cultural resources legislation to date, mostly through establishing the National Register of Historic Places (NRHP). The NHPA requires federal agencies to address their cultural resources, which are defined as any prehistoric or historic district, site, building, structure, or object. Section 110 of the NHPA requires federal agencies to inventory and evaluate their cultural resources, and Section 106 requires them to determine the effect of federal undertakings on those potentially eligible for the NRHP. Lahaina is located in the western part of Maui County, in Hawaiʻi. The Spring House, erected circa 1823, is currently scheduled for demolition due to its major fire damages. This report documents the building to the standards of the Historic American Buildings Survey and includes a historic context, architectural descriptions, photographs, and measured drawings. This report satisfies Sections 106 and 110 of the National Historic Preservation Act of 1966 as amended and will be used by FEMA to document the building before its demolition.

15 Sep 2025

Fiber-Reinforced-Polymer (FRP) Composite Sandwich Panel Barge Impact Modeling and Repair Testing: Dynamic and Static Finite Element Analysis (FEA) Predictions for Impact and Flexural Testing Validated with Experiments

Abstract: The US Army Engineer Research and Development Center has studied the functionality, durability, and structural integrity of fiber-reinforced-polymer (FRP) composite materials in civil works infrastructure. Compared to traditional materials like steel, composites offer a high strength-to-density ratio and excellent resistance to environmental degradation. The purpose of this study is to evaluate the dynamic response of FRP composite sandwich panels subjected to a barge impact with typical masses and velocities. A finite element model was created for FRP composite sandwich panels by incorporating cohesive interaction properties to evaluate the damage between three-dimensional (3D) layers. To validate the model, several FRP composite sandwich panels were experimentally subjected to low-velocity impacts and compared to the models. Moreover, flexural experiments were performed to determine the reduction of structural performance after impact and the efficacy of two different repair methods. Numerical predictions were developed to explore the damage caused by the interfaces of FRP composite layers. Load, deflection, and velocities were obtained experimentally and with finite element models.

12 Sep 2025

Veterans Administration Fourth Generation Historic Context

Abstract: The period of significance for fourth generation of Veterans Administration (VA) medical centers ranges from 1955 to 1977. This period encapsulates a surge of VA medical center construction with congressional funding, dating from the release of the 1955 congressional report Nonbed Betterments in Veterans Administration Hospitals—Need for Renovation and Construction to the adoption of the Veterans Administration Medical Facilities Acquisition Act of 1977. New medical centers constructed by the VA during this time may be eligible under Criterion A for their association with health care and medicine, specifically the development of education and research relationships with medical schools. These partnerships advanced therapies, technology, and hospital operation in support of the VA’s mission to provide quality medical care for veterans. To support these partnerships, VA medical centers were commonly built adjacent to or within medical school complexes. Additionally, fourth generation VA medical centers may be eligible under Criterion C for embodying distinctive architecture or landscape architecture characteristics of mid-century modern hospitals or representing an important contribution in a significant architect’s career. This report provides a comprehensive historic context for the design, construction, and operation of new fourth generation VA medical centers in support of Section 110 of the National Historic Preservation Act of 1966 (NHPA). It does not include other VA medical facilities constructed during this period, such as psychiatric and rehabilitation centers, nursing homes, domiciliaries, and research and education buildings.

12 Sep 2025

Literature Review and Environmental Concerns Regarding Lithium-Ion Batteries

Abstract: This study investigates the environmental and technical challenges associated with the production, use, and recycling of lithium-ion batteries (LIBs), which are critical components in consumer electronics and electric vehicles (EVs). As the demand for LIBs continues to grow, the concerns related to the mining and processing of key materials like lithium, cobalt, nickel, and manganese are also increasing. The extraction and refining processes for these metals are energy-intensive and produce significant environmental impacts, including greenhouse gas emissions, toxic waste, and resource depletion. The review emphasizes the need for improved recycling technologies and sustainable practices to mitigate the environmental footprint of LIBs and secure a more sustainable supply chain for the future of clean energy storage solutions. This study also analyzes LIB components to assess the presence of environmentally hazardous metals and compounds. Advanced analytical techniques like X-ray fluorescence (XRF), inductively coupled plasma–optical emission spectroscopy (ICP-OES), and Fourier transform infrared (FTIR) spectroscopy revealed significant leaching of toxic elements and PFAS from battery parts, underscoring the environmental and health risks associated with improper disposal. The findings highlight the urgent need for improved recycling methods to mitigate these risks and enhance the sustainability of LIB use.

9 Sep 2025

Bayesian Updating of Fatigue Crack Growth Parameters for Failure Prognosis of Miter Gates

Abstract: Navigable waterways play a vital role in efficient transportation of millions of tons of cargo annually. Inland traffic must pass through a lock, which consists of miter gates. Failures and closures of these gates can significantly disrupt waterborne commerce. Miter gates often experience fatigue cracking due to their loading and welded connections. Repairing every crack can lead to excessive miter gate downtime and serious economic impacts. If the rate of crack growth is shown to be sufficiently slow, immediate repairs may be deemed unnecessary, and this downtime can be avoided. Paris’ law is often obtained from laboratory testing with detailed crack measurements of specimens with relatively simple geometry. However, its parameters for an in situ structure will likely deviate from those predicted from physical testing due to variations in loading and materials and a more complicated geometry. To improve Paris’ law parameter prediction, we propose a framework that utilizes convenient vision-based tracking of crack evolution in the laboratory and the field and numerical model estimation of stress intensity factors. This study’s methodology provides an efficient tool for Paris’ law parameter prediction that can be updated as more data become available through vision-based monitoring and provide actionable information.