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  • Unified Facilities Criteria and Unified Facilities Guide Specifications for Sustainable Military Construction : Concrete, Asphalt, Wood, and Life-Cycle Assessment Perspectives

    Abstract: Construction materials such as concrete, asphalt, and wood are essential components for Department of Defense (DoD) Military Construction (MILCON) and construction for contingency operations around the world. From housing facilities, to airfields, to magazines and hardened structures, each of these materials fulfill numerous Army building applications. However, greenhouse gas (GHG) emissions stemming from the manufacturing, application, maintenance, and disposal of concrete and steel exact a significant climate burden. Thus, due to their pervasive use and commodity status, the advancement of sustainable concrete, asphalt, and wood materials are a critical driver for GHG mitigation. This report communicates a first step toward decarbonization-focused updates to UFC and UFGS by outlining major specifications related to concrete, asphalt, and wood with near- and long-term strategies to facilitate modernization. The Engineer Research and Development Center (ERDC) is poised to make a significant impact on the identification and integration of sustainable materials to meet regulatory goals for the re-duction of GHG emissions in MILCON. New guidance will be integrated into UFC and UFGS by leveraging unique re-search, development, test, and evaluation (RDT&E) capabilities in materials science, life-cycle assessment, and federal relationships with discipline working groups
  • Full-Scale Evaluation of Saltwater Concrete for Airfield Pavement Construction and Repair

    Abstract: The US Navy has a need to rapidly construct concrete facilities onshore to support contingency operations. Mixing water for concrete is typically specified to be freshwater; however, in many scenarios there are limited amounts of freshwater available for construction. Thus, use of readily available saltwater would be advantageous. This project’s objective was to evaluate the suitability of saltwater as a replacement for freshwater for producing concrete airfield pavement under relevant operational scenarios. Three full-scale test sections were constructed, and performance was evaluated in the context of relatively short design life requirements. First, direct comparison slabs of freshwater and saltwater concrete were constructed and exposed to ambient environmental conditions for one year; periodic concrete strength measurements were made. Next, 8 in. thick and 11 in. thick saltwater concrete pavements were constructed then subjected to P-8 aircraft accelerated loading. Finally, four airfield damage repair techniques were executed using saltwater and subjected to accelerated P-8 aircraft loading. Saltwater concrete performance was found to be similar to freshwater concrete for all scenarios investigated. The overall conclusion was that saltwater can be used in place of freshwater for concrete airfield pavement construction and repair for short- to medium-term use (1–2 yr) with no meaningful impact to mission requirements.
  • 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.
  • Pittsburgh District: Research takes regular ‘Conk Creet’ to next level of cold weather construction

    Engineers have developed and tested concrete mixtures to overcome all kinds of environmental demands, but one construction category has evaded engineers for centuries until now: cold weather.
  • ERDC leads advances in sustainable materials for military construction

    Climate change is a major priority for the Biden administration, which has set a goal to reach net zero emissions by no later than 2050. As the Army works to meet these goals and accomplish the objectives set in its own Climate Strategy, it has begun to focus more attention on one of its biggest emissions drivers: construction activities related to its vast inventory of buildings.
  • Residual Strength of a High-Strength Concrete Subjected to Triaxial Prestress

    Abstract: This study investigates simplified mechanical loading paths that represent more complex loading paths observed during penetration using a triaxial chamber and a high-strength concrete. The objective was to determine the effects that stress-strain (load) paths have on the material’s unconfined compressive (UC) residual strength. The loading paths included hydrostatic compression (HC), uniaxial strain in compression (UX), and uniaxial strain load biaxial strain unload (UXBX). The experiments indicated that the load paths associated with nonvisible microstructural damage were HC and UX—which produced minimal impact on the residual UC strength (less than 30%)—while the load path associated with visible macro-structural damage was UXBX, which significantly reduced the UC strength (greater than 90%). The simplified loading paths were also investigated using a material model driver code that was fitted to a widely used Department of Defense material model. Virtual experiment data revealed that the investigated material model overestimated material damage and produced poor results when compared to experimental data.
  • 23-052 USACE to rehabilitate and improve Russel Creek Canal

    WALLA WALLA, Wash. – This winter, the U.S. Army Corps of Engineers, Walla Walla District will begin a rehabilitation and improvement project on Russel Creek Canal. The canal, a part of the Mill Creek Flood Control Project, is located downstream of Bennington Lake and runs approximately one mile from the lake to Russel Creek.
  • Stronger, Lighter, More Durable: Ultra-High Performance Concrete is key to a more sustainable and modern infrastructure network

    As the U.S. Army Corps of Engineers (USACE) works to modernize the nation’s infrastructure, it does so at a time when existing infrastructure components are operating well past their original lifespans. In the case of many of the locks supporting inland navigation, new techniques and technologies are critical to make sure lock facilities – some built in the 1930s – continue operating for another 100 years or more.
  • 22-073 USACE and Mill Creek Flood Control Zone District sign Project Partnership Agreement

    Walla Walla, Wash. – The U.S. Army Corps of Engineers, Walla Walla District, and Mill Creek Flood Control Zone District signed a Project Partnership Agreement for the Mill Creek Section 205 Project on November 21.
  • Evaluation of a Prototype Integrated Pavement Screed for Screeding Asphalt or Concrete Crater Repairs

    Abstract: Finishing, or screeding, the hot mix asphalt or rapid-setting concrete surface of a crater repair is important for rapid airfield damage recovery (RADR) since it determines the aircraft ride surface quality. The objective of RADR repairs is to expediently produce a flush repair, defined as ±0.75 in. of the surrounding pavement surface, with minimal logistical and personnel burden. Multiple screeds were previously evaluated; the most recent project proposed a prototype design of a telehandler-operated integrated screed for both small and large repairs using asphalt or concrete. This project’s objective was to finalize the prototype design and fabricate and test the prototype RADR screed. The prototype RADR screed was successful for small repairs (8.5×8.5 ft). Large repairs (30×30 ft) were generally successful with modest repair quality criteria (RQC) issues being the only notable deficiencies. Large concrete repair RQC issues were attributed to plastic formwork movement, and large asphalt repair RQC issues were attributed to compaction issues or improper roll-down factors. Methods to mitigate these factors were investigated but should be further evaluated. Overall, the RADR screed was successful from technical perspectives but, functionally, is 600-800 lb overweight. Weight reduction should be considered before entering production.