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  • PUBLICATION NOTICE: Effects of Boric Acid and Water Content on Fundamental Properties of Proprietary Magnesium Phosphate Cement (MPC) Products

    Abstract: Magnesium phosphate cements (MPCs) have been used for decades in proprietary products for pavement repairs. However, products with high exothermic temperatures have short working times, and research is needed to overcome these unfavorable characteristics. The effects of different boric acid and water contents on the fundamental properties of concrete was investigated through 34 trial batch modifications on the following commercially available MPC products: (1) Premier Magnesia’s PREMag PGDM, (2) BASF Master Builder’s MasterEmaco T545, and (3) CeraTech Inc.’s Pavemend TR. Overall results indicated that the increase of boric acid and water content produced favorable decreased temperatures and increased set times but retardation in the early age development of compressive strength. Modifications in the PREMag PGDM product resulted in poor workability, inaccurate time of setting due to a thixotropic nature, and unacceptable compressive strength loss. The Pavemend TR product was significantly affected by the addition of boric acid resulting in nonrecoverable compressive and bond strength loss, excessive expansions, failure at low freezing and thawing cycles, and unacceptable times of setting for rapid-repair applications. The T545 product showed promising performance with 28-day recovery in compressive, flexural, and bond strengths and minimal differences in other properties when compared to the control mixture.
  • PUBLICATION NOTICE: Preliminary Assessment of Landform Soil Strength on Glaciated Terrain in New Hampshire

    Abstract: Accurate terrain characterization is important for predicting off-road vehicle mobility. Soil strength is a significant terrain characteristic affecting vehicle mobility. Collecting soil strength measurements is laborious, making in-situ observations sparse. Research has focused on providing soil strength estimates using remote sensing techniques that can provide large spatial and temporal estimates, but the results are often inaccurate. Past attempts have quantified the soil properties of arid environments using landform assessments; yet many military operating environments occupy high latitude regions with landscapes dominated by glacial deposits. This study took preliminary strength measurements for glacial landforms deposited from the Laurentide Ice Sheet in New England. A range of common glacial landforms were sampled to assess shear strength, bearing capacity, and volumetric moisture content. Glacial outwash landforms had the highest average shear strengths, glacial deltas the lowest. There was a significant negative correlation between silt content and shear strength of the soil, a significant positive correlation between bearing capacity and clay content, and a significant negative correlation with sand content. Moisture content of soils was inversely correlated to the abundance of gravel in the deposit. This work provides initial insight to this approach on glaciated terrain, but continued sampling will provide more robust correlations.
  • PUBLICATION NOTICE: Improved Vehicle Mobility by Using Terrain Surfacing Systems

    Abstract: Even for military vehicles designed with superior off-road capabilities, problematic soil conditions can impede mobility, particularly when many vehicles need to traverse the same path. Loose sands with little shear strength or wet silts or clays with little bearing capacity can deform rapidly under traffic. U.S. Army Engineer Research and Development Center researchers conducted field testing over several terrain conditions to measure performance of terrain surfacing systems designed to improve vehicle mobility. Soil conditions included poorly-graded sand, medium-strength silt, weak marsh, and two different slope conditions. Five different terrain surfacing, or matting systems, were tested that included four commercial variants and one U.S. government design. All testing took place at the ERDC Ground Vehicle Terrain Surfacing Test Facility in Vicksburg, Mississippi. Military test vehicles included a Marine Tactical Vehicle Replacement, Common Bridge Transporter, and M1 Abrams tank. Results from the testing showed that all matting systems provided notable improvement in the number of allowable vehicle passes over soft sands. Results varied for the different systems over weaker soils, with performance improved for those matting systems having thicker and stiffer panels. However, improved performance among matting systems came with a sacrifice of increased logistical burden. Data presented here-in include detailed site characteristics and soil deformation as a function of traffic.
  • PUBLICATION NOTICE: Laboratory Characterization of Rapid-Setting Flowable Fill

    Abstract: Utility Fill One-Step 750® is a rapid-setting flowable fill product that has previously been validated in numerous full-scale demonstrations as an expedient backfill solution for Rapid Airfield Damage Recovery. Although the field performance of Utility Fill One-Step 750® has been extensively documented, a full laboratory characterization has not been conducted. This report analyzes and documents results from several laboratory tests conducted at two water to-product ratios. The tests conducted are based on the suite of tests that make up the triservice spall repair certification program used for rapid-setting concrete products. Tests include strength and set time-related properties, typical parameter control tests for concrete, and tests to determine the mineralogy and chemical makeup of the material. Long-term expansion and contraction properties were also tested. The data presented herein are intended to provide an overall assessment of Utility Fill One-Step 750® and to provide reasonable estimates of various design parameters. The results can be used as a basis for the future development of a formal laboratory certification protocol to down-select other rapid-setting flowable fill products for further evaluation.
  • PUBLICATION NOTICE: Application of Chirp Acoustic Sub-Bottom Data in Riverine Environments: Identification of Underlying Rocky Hazards at Cape Girardeau, Missouri, and Thebes, Illinois

    NOTE: A revised version of the report MRG&P Report No. 31 has been published. While the link below remains valid, the PDF attached to the record is new. It is now 47 pages instead of 45 pages after the changes made. Please update your records as needed.
  • PUBLICATION NOTICE: Lake Providence to Old River Geomorphology Assessment

    Abstract: This report integrates information from previous geomorphic studies coupled with new analysis to provide a comprehensive geomorphic characterization of the Lake Providence (River Mile [RM] 487.2 Above Head of Passes [AHP]) to Old River Control Complex, (RM 317 AHP) reach from the early-1800s to present. Individual components of this study included the following: historical geomorphic studies, development of an events timeline, specific gage records, stage and flow duration trends, trends in water surface slopes, bed material studies, suspended sediment data, channel geometry data, and effects of channel improvement features (cutoffs, dike, revetment, and dredging). These individual assessments were consolidated to develop an overall assessment of how the study reach has evolved since the early-1800s.
  • Hurricane Risk Reduction Measures coming to the Rockaways

    The U.S. Army Corps of Engineers, New York District announces the first contract award for the East Rockaway Inlet to Rockaway Inlet and Jamaica Bay, New York Coastal Storm Risk Reduction Project. This is the first of several contracts that will provide nearly $600 million in federal investment for the construction of storm risk reduction infrastructure on both the Atlantic Ocean shoreline and the Jamaica Bay shoreline of the Rockaway Peninsula.
  • 20-021 Corps seeks public input for Ice Harbor Master Plan Revision

    BURBANK, Wash.– The U.S. Army Corps of Engineers’ Walla Walla District (Corps) invites the public to provide scoping comments for its upcoming revision of the Ice Harbor Master Plan. The Corps will be accepting comments from May 1 through June 15, 2020.
  • MKARNS Nav Notice SWL 20-24 Dredging and Sailing Instruction Update NM 23, NM 49.9

    MKARNS - Dredging at NM 23(noted in SWL 20-23) is complete and the sailing instruction (noted in SWL 20-05) is lifted.
  • PUBLICATION NOTICE: Baldcypress (Taxodium distichum) at the Wallisville Lake Project: A Review of Applicable Literature and Management Considerations

    Abstract: Changing hydropatterns within the Wallisville Lake Project, near the mouth of the Trinity River in Chambers and Liberty Counties, Texas, have the potential to alter baldcypress forest resiliency. Increasing water levels support saltwater barrier operations while maintaining navigation and recreational access. However, potential impacts of increased water levels on the baldcypress forests are of particular concern because these ecosystems provide unique ecological value and wildlife habitat. The maintenance, succession, and resiliency of baldcypress under various flooding, salinity, and inundation regimes remain poorly defined and pose challenges to resource managers. This report reviews available literature pertaining to salinity and inundation impacts to baldcypress forests. Specific emphasis is placed on the ecological effects of water quality and quantity on the health and persistence of baldcypress. The information gathered in this report is intended to supplement material in the Wallisville Lake Project Water Control Manual to improve management of baldcypress forest conditions and avoid negative ecological impacts. Additionally, this report provides management considerations designed to maintain or enhance baldcypress forests within the Wallisville Lake Project.

Mississippi Valley Division

Institute for Water Resources

South Pacific Division

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