29 May 2024

Publications of the U.S. Army Engineer Research and Development Center; Appendix H : FY23 (October 2022-September 2023)

Abstract: Each year, the US Army Engineer Research and Development Center (ERDC) publishes more than 200 reports through the Information Technology Laboratory’s Information Science and Knowledge Management (ISKM) Branch, the publishing authority for ERDC. Annually since 2017, ISKM has compiled a list of the last fiscal year’s publications. This Appendix H to the original collection includes ERDC publications issued October 2022 through September 2023. The publications are grouped according to the technical laboratories or technical program for which they were prepared, and the preface includes procedures for obtaining ERDC reports. Through this compilation, online distribution, and physical collections, ISKM continues to support ERDC, the Army, and the nation.

29 May 2024

Performance of Army Corps of Engineers Mat System Using Anchorless Connections: A Follow-on Study of Site Stabilization for the Improved Ribbon Bridge Bridge Supplemental Set

Abstract: The US Army Engineer Research and Development Center conducted testing of the Army Corps of Engineers mat system with improved anchorage and connection hardware. Low-profile screw anchors replaced the ground anchorage of the existing system to reduce wear to tracks and wheels of vehicles while trafficking the system. Anchorless connections allowed the system to be placed over soils where the use of screw anchorage would be obstructed or would cause hazards to trafficking vehicles. Test tracks were constructed to evaluate the matting system with new anchorage and connection hardware over three different soils of weak sand and clay. Channelized traffic was applied to the test tracks using a loaded common bridge transporter. Performance of the updated system was evaluated with respect to results from previous testing, indicating that the improved anchorage and connection hardware increased the versatility of the matting system without sacrificing system performance.

29 May 2024

Finite Element, Petrographic, and Mechanical Analyses of Field-Cored Concrete Fairlead Beam Anchor Rods from Luke Air Force Base

Abstract: The fairlead beam is used to accomplish installation of the Barrier Arresting Kit 12 energy absorber for setback aircraft arresting system (AAS) installations at permanent operating facilities. Typical fairlead beams are affixed to a Portland cement concrete (PCC) foundation pad by a series of anchor assemblies made up of steel anchor rods set in grout inside galvanized pipe sleeves. US Air Force Civil Engineering Center (AFCEC) subject matter experts have identified a pattern of premature failures in these steel anchor assemblies when they are nondestructively inspected during AAS overhauls. The US Army Engineer Research and Development Center was tasked by AFCEC to investigate potential reasons for these premature failures. This report outlines methods and results of a finite element analysis of the anchorage, a visual and petrographic analysis of field-cored PCC anchor rods from Luke Air Force Base, and a mechanical analysis of specimens taken from the anchor rods within the PCC cores. Multiple modes of PCC distress were observed, and corrosion was evident in and around the anchor assemblies. Mechanical testing of specimens from the anchor rods indicated that an inferior grade of steel was used to fabricate these particular assemblies. Finally, observed deviations from design intention are discussed.

28 May 2024

Statistical Analysis of Storm Surge and Seiche Hazards for Lake Erie

Abstract: Storm surge and seiche events are generally forced by severe storms, initially resulting in a wind-driven super elevation of water level on one or more sides of a lake (surge) followed by a rebound and periodic oscillation of water levels between opposing sides of the lake (seiche). These events have caused flooding along Lake Erie and significant damages to coastal communities and infrastructure. This study builds upon statistical analysis methods initially developed for the 2012 federal interagency Great Lakes Coastal Flood Study. Using the Coastal Hazards System's stochastic Storm Simulation (StormSim) suite of tools, including the Probabilistic Simulation Technique (PST), and regional frequency model, historical extreme events were assessed in a local frequency analysis and a regional frequency analysis to quantify the annual exceedance frequency (AEF) of WLD events specific to Lake Erie. The objective of this study was to quantify AEFs of storm surge and seiche hazards to provide a better understanding of these events to aid flood mitigation and risk reduction for lakeside properties.

22 May 2024

Beneficial Use of Dredged Material in the Atlantic Intracoastal Waterway: Approaching the Regulatory Process

Purpose: Following the Chief of Engineer’s January 2023 goal to expand the beneficial use of dredged material (BUDM), the US Army Corps of Engineers (USACE) strives to apply new and creative ways to increase utilization of dredged materials from a historic 30%–40% to 70% by 2030. As USACE Savannah District (SAS) increases BUDM efforts, a critical component of this transition is understanding and navigating the regulatory requirements. This Technical Note outlines the regulatory process for placement of dredged material in Georgia, identifies challenges and institutional barriers, and offers potential solutions to streamlining the overall process. By increasing the ease of navigating the regulatory process, USACE can facilitate an increase in BUDM and Engineering with Nature® (EWN®) projects in Georgia, and potentially other projects employing nature-based solutions (NBS). While regulatory details may vary from state to state, the Georgia example presented here can serves as a road map for the general types of regulatory procedures and potential hurdles found nationwide.

21 May 2024

Low Sill Control Structure: Physical Modeling Investigation of Riprap Stability Downstream of End Sill

The model investigation reported herein describes the process to model and analyze the stability of scaled riprap in the existing 1:55 Froude-scaled Low Sill Control Structure physical model. The existing model is a fixed-bed model, so modifications were made to create a testing section for the scaled stone. Three separate gradations of scaled riprap were tested at varying boundary conditions (discharge, head and tailwater elevations, and gate openings). Each test was surveyed using lidar for pre to posttest comparisons. It was found that Gradation B remained stable throughout the tests in the physical model.

21 May 2024

Lessons in Rearing Mealworms for Plastics Degradation

Purpose: The primary objective of this research is to determine if plastics-degrading gut bacterial communities from a nonoptimal insect host can be successfully transplanted into the gut of the optimal mealworm host for large scale composting. To achieve this goal, foundational questions about basic mealworm husbandry needed to be addressed, including proper housing and feeding regimes, expected plastics degradation rates, and survivability on plastics as a food source. This technical note serves as a mealworm husbandry protocol and a guide for lessons learned in the early stages of experimentation dealing with establishment of plastics-degrading mealworm colonies.

21 May 2024

Engineering With Nature: An Atlas, Volume 3

Abstract: Engineering With Nature: An Atlas, Volume 3 showcases EWN principles and practices “in action” through 58 projects from around the world. These exemplary projects demonstrate what it means to partner with nature to deliver engineering solutions with triple-win benefits. The collection of projects included were developed and constructed by a large number of government, private sector, nongovernmental organizations, and other organizations. Through the use of photographs and narrative descriptions, the EWN Atlas was developed to inspire interested readers and practitioners with the potential to engineer with nature.

21 May 2024

Site Selection and Conceptual Designs for Beneficial Use of Dredged Material Sites for Habitat Creation in the Lower Columbia River

Abstract: Channel maintenance in most major rivers throughout the United States requires ongoing dredging to maintain navigability. The US Army Corps of Engineers explores several options for placement based on sediment characteristics, material quantity, cost, operational constraints, and minimization of potential adverse effects to existing resources and habitat. It is a priority to beneficially reuse dredged sediments to create habitat and retain sediments within the river system whenever possible. Nonetheless, there can be discrepancies among state and federal resource agencies, landowners, tribes, and various other stakeholders about what constitutes a benefit and how those benefits are ultimately weighed against short- and long-term tradeoffs. This work leveraged prior Regional Sediment Management efforts building consensus among stakeholders on a suite of viable strategies for in-water placement in the lower Columbia River. The goal was to identify suitable locations for applying the various strategies to maximize habitat benefits and minimize potential adverse effects. A multistep site-selection matrix was developed with criteria accounting for existing site conditions, overall placement capacity, tradeoffs, long-term maintenance, cost, stakeholder concerns, and landscape principles in the context of other habitat restoration projects implemented in the lower river. Three highly ranked sites were selected for conceptual design and exemplify results of collaborative beneficial use implementation.

20 May 2024

Railroad Infrastructure Management: A Novel Tool for Automatic Interpretation of GPR Imaging to Minimize Human Intervention in Railroad Inspection

Abstract: Regular monitoring and inspection of military railroad tracks are necessary to ensure the safe transportation of military freight. Manual railroad inspection has drawbacks and limitations that can impact accuracy and efficiency. This study introduces a novel tool designed to automate Ground Penetrating Radar (GPR) imaging interpretation for railroad ballast condition assessment, aiming to reduce human intervention in inspections. The tool uses advanced signal processing techniques, such as the Short-Time Fourier Transform (STFT) and Wavelet Transform (WT), to quantify ballast fouling levels accurately, enhancing maintenance and safety protocols for railroad tracks. Validation through comprehensive testing, including two case studies, demonstrates the tool’s superior efficacy over traditional manual inspection methods. This research represents a pivotal step towards more efficient and reliable infrastructure management, ensuring critical railroad systems’ safety and operational integrity.