10 May 2021

Risk-Based Prioritization of Operational Condition Assessments: Stakeholder Analysis and Literature Review

Abstract: The US Army Corps of Engineers (USACE) operates, maintains, and manages more than $232 billion worth of the Nation’s water resource infrastructure. Using the Operational Condition Assessment (OCA) system, the USACE allocates limited resources to assess conditions and maintain assets in efforts to minimize risks associated with asset performance degradation. Currently, OCAs are conducted on each component within a facility every 5 years, regardless of the component’s risk contribution. The analysis of risks associated with Flood Risk Management (FRM) facilities, such as dams, includes considering how the facility contributes to its associated FRM watershed system, understanding the consequences of degradation in the facility’s performance, and calculating the likelihood that the facility will perform as expected given the current OCA condition ratings of critical components. This research will develop a scalable methodology to model the probability of failure of components and systems that contribute to the performance of facilities in their respective FRM systems combined with consequences derived from hydrological models of the watershed to develop facility risk scores. This interim report documents the results of the first phase of this effort, stakeholder analysis and literature review, to identify candidate approaches to determine the probability of failure of a facility.

4 May 2021

Joint Rapid Airfield Construction (JRAC) Program 2004 Demonstration Project--Fort Bragg, North Carolina

Abstract: This report describes the demonstration of technologies and procedures developed during April 2002 and May 2004 under the Joint Rapid Airfield Construction (JRAC) Program. The demonstration took place at Sicily Landing Zone (LZ) at Fort Bragg, NC, in July of 2004. The objective of the exercise was to demonstrate the procedures and technologies developed under the JRAC Program by rapidly building two parking aprons capable of supporting C-130 transport aircraft taxiing and parking operations. The exercise was conducted under continuous 24-hr operations to simulate a real-world rapid construction environment. Apron 1 (north apron) was constructed using two technologies, one-half being ACE™ Matting and the other half being a cement-polymer stabilized soil surface. Apron 2 (south apron) was constructed solely of a fiber-cement-stabilized soil system. Both aprons were treated with a polymer emulsion surface application to form a sealed surface against abrasion and water infiltration. The entire construction of both aprons required 76 hr, with Apron 1 finished in 48 hr. The construction of Apron 1 was validated by operation of a C-130 aircraft approximately 31 hr after completion with success and high praises from the aircraft flight crew on the stability and surface of the apron, as well as its dust-abating characteristics.

4 May 2021

Laboratory characterization of Cor-Tuf Baseline and UHPC-S

Abstract: This experimental effort is part of a larger program entitled Development of Ultra-High-Performance Concrete Tools and Design Guidelines. This program operates in accordance with an agreement concerning combating terrorism research and development between the United States of America Department of Defense and the Republic of Singapore Ministry of Defence. The objective of the program is to develop a better understanding of the potential benefits that may be achieved from the application of ultra-high-performance concrete (UHPC) materials for protective structures. The specific effort detailed in this report will provide insight into laboratory-scale mechanical properties of Cor-Tuf and a proprietary material termed UHPC-Singapore (UHPC-S).

4 May 2021

Study of Maintenance of High Performance Sustainable Buildings (HPSB)

Abstract: A study was performed by the Energy Branch of the US Army Engineer Research and Development Center, Construction Engineering Research Laboratory, on behalf of the US Army Installation Management Command under the Installation Technology Transition Program. The focus of the study was related to maintainability and operability issues associated with High Performance Sustainable Buildings (HPSBs). This study was conducted primarily based on information gleaned from telephone and web conference discussions with installation Directorate of Public Works personnel including Operation and Maintenance (O&M) Chiefs, energy managers, maintenance supervisors, and maintenance technicians. Experiences with HPSBs varied from installation to installation. For example, some installations had very positive experiences with photovoltaic (PV) arrays while other sites questioned their practicality due to maintainability problems. One site noted that PV technologies are changing so rapidly that procuring spare/repair parts becomes difficult or impossible when vendors discontinue supporting their older technologies or manufacturers go out of business. Based on discussions with the installation O&M personnel, a table of pro and con recommendations for 25 technologies, which are commonly implemented on HPSBs, was prepared and is included in this report.

4 May 2021

Microscale Dynamics between Dust and Microorganisms in Alpine Snowpack

ABSTRACT:  Dust particles carry microbial and chemical signatures from source regions to deposition regions. Dust and its occupying microorganisms are incorporated into, and can alter, snowpack physical properties including snow structure and resultant radiative and mechanical properties that in turn affect larger-scale properties, including surrounding hydrology and maneuverability. Microorganisms attached to deposited dust maintain genetic evidence of source substrates and can be potentially used as bio-sensors. The objective of this study was to investigate the impact of dust-associated microbial deposition on snowpack and microstructure. As part of this effort, we characterized the microbial communities deposited through dust transport, examined dust provenance, and identified the microscale location and fate of dust within a changing snow matrix. We found dust characteristics varied with deposition event and that dust particles were generally embedded in the snow grains, with a small fraction of the dust particles residing on the exterior of the snow matrix. Dust deposition appears to retard expected late season snow grain growth. Both bacteria and fungi were identified in the collected snow samples.

4 May 2021

Utilizing Data from the NOAA National Data Buoy Center

Purpose: This Coastal and Hydraulics Engineering Technical Note (CHETN) guides users through the quality control (QC) and processing steps that are necessary when using archived U.S. National Oceanic and Atmospheric Administration (NOAA) National Data Buoy Center (NDBC) wave and meteorological data. This CHETN summarizes methodologies to geographically clean and QC NDBC measurement data for use by the U.S. Army Corps of Engineers (USACE) user community.

4 May 2021

First Generation Automated Assessment of Airfield Damage from LiDAR Point Clouds

Abstract: This research developed an automated software technique for identifying type, size, and location of man-made airfield damage including craters, spalls, and camouflets from a digitized three-dimensional point cloud of the airfield surface. Point clouds were initially generated from Light Detection and Ranging (LiDAR) sensors mounted on elevated lifts to simulate aerial data collection and, later, an actual unmanned aerial system. LiDAR data provided a high-resolution, globally positioned, and dimensionally scaled point cloud exported in a LAS file format that was automatically retrieved and processed using volumetric detection algorithms developed in the MATLAB software environment. Developed MATLAB algorithms used a three-stage filling technique to identify the boundaries of craters first, then spalls, then camouflets, and scaled their sizes based on the greatest pointwise extents. All pavement damages and their locations were saved as shapefiles and uploaded into the GeoExPT processing environment for visualization and quality control. This technique requires no user input between data collection and GeoExPT visualization, allowing for a completely automated software analysis with all filters and data processing hidden from the user.

4 May 2021

Army R-22 Refrigerant Phase-Out Strategy

Abstract: R-22 (also known as HCFC-22) is one of the most widely used refrigerants in U.S. Army air-conditioning and refrigeration (AC&R) systems since the phase-out of R-12 refrigerant in 1995. The need to phase out R-22 is at-tributed to its global warming potential and high ozone-depleting capability. The U.S. Army has tens of thousands of aging AC&R systems that will remain dependent on R-22, or one of the recently developed substitutes for R-22, until they reach the end of their operational life. This project conducted a survey to understand the current R-22 usage and types of R-22 AC&R equipment that are in use across Instal-lation Management Command (IMCOM) installations. This study describes several methods to remove or retrofit R-22 from typical AC&R equipment and implementation strategies to meet the stated goal of eliminating R-22 from IMCOM installations. The scope of this project included the review of BUILDER SMS data for IMCOM installations, which included data on 13,000 pieces of comfort cooling equipment for 31 installations. The report also provides an analysis of several R-22 alternatives and their physical properties and compatibility. Mission critical tactical cooling that uses R-22 refrigerant was not within the scope of this project.

4 May 2021

Monitoring the Milwaukee Harbor Breakwater: An Engineering With Nature® (EWN®) Demonstration Project

Abstract: The US Army Corps of Engineers (USACE) maintains breakwaters in Mil-waukee Harbor. USACE’s Engineering With Nature® (EWN®) breakwater demonstration project created rocky aquatic habitat with cobbles (10–20 cm) covering boulders (6–8 metric tons) along a 152 m section. A prolific population of Hemimysis anomala, an introduced Pontocaspian mysid and important food source for local pelagic fishes, was significantly (p < .05) more abundant on cobbles versus boulders. Food-habits data of ale-wife (Alosa pseudoharengus) and rainbow smelt (Osmerus mordax) pro-vided evidence that H. anomala were a common prey item. Night surveys and gill netting confirmed O. mordax preferred foraging on the cobbles (p < .05) and consumed more H. anomala than at the reference site (p < .05). H. anomala comprised a significant portion of the diets of young-of-the-year (YOY) yellow perch (Perca flavescens), YOY largemouth bass (Micropterus salmoides), and juvenile rock bass (Ambloplites rupestris) caught on the breakwater. The natural features’ construction on the break-water increased the available habitat for this benthopelagic macroinverte-brate and created a novel ecosystem benefiting forage fish and a nursery habitat benefiting nearshore game fish juveniles. These data will encour-age the application of EWN concepts during structural repairs at other built navigation infrastructure.

4 May 2021

Ice Fog Monitoring Near Fairbanks, AK

ABSTRACT:  Ice fog events, which occur during the Arctic winter, result in greatly decreased visibility and can lead to an increase of ice on roadways, aircraft, and airfields. The Fairbanks area is known for ice fog conditions, and previous studies have shown these events to be associated with moisture released from local power generation. Despite the identified originating mechanism of ice fog, there remains a need to quantify the environmental conditions controlling its origination, intensity, and spatial extent. This investigation focused on developing innovative methods of identifying and characterizing the environmental conditions that lead to ice fog formation near Fort Wainwright, Alaska. Preliminary data collected from December 2019 to March 2020 suggest that ice fog events occurred with temperatures below −34°C, up to 74% of the time ice fog emanated from the power generation facility, and at least 95% of ice particles during ice fog events were solid droxtals with diameters ranging from 7 to 50 µm. This report documents the need for frequent and detailed observations of the meteorological conditions in combination with photographic and ice particle observations. Datasets from these observations capture the environmental complexity and the impacts from energy generation in extremely cold weather conditions.