30 Apr 2020

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.

29 Apr 2020

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.

29 Apr 2020

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.

29 Apr 2020

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.

29 Apr 2020

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.

29 Apr 2020

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.

28 Apr 2020

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.

28 Apr 2020

PUBLICATION NOTICE: Lower Columbia River Adaptive Hydraulics (AdH) Model: Development, Water Surface Elevation Validation, and Sea Level Rise Analysis

Abstract: A numerical model of the Lower Columbia River, validated to water surface elevations, has been generated using the Adaptive Hydraulics (AdH) code. The model boundary conditions include an ocean tidal boundary and five inflows: the Lewis, Cowlitz, Willamette, and Sandy Rivers, and the Columbia River at Bonneville Lock and Dam. The model, which spans approximately 146 river miles, accurately reproduces water surface elevations measured in the field at several locations along the model domain. An examination of the AdH model’s Friction Library was also conducted. The Friction Library was used in this application to estimate the effects of pile dikes. Rather than model individual piles in the model mesh, the piles were modeled using the Friction Library’s submerged vegetation material type. Through testing of this application, it was determined that the Friction Library approach, which enhances model run time and efficiency, can accurately reproduce the global effects of pile dike fields. Additionally, the validated model was used to analyze three sea level rise (SLR) scenarios, which correspond to predicted SLR at Astoria, OR, at 50, 75, and 100 years from the present (0.5 meter [m], 1.0 m, and 1.5 m, respectively).

28 Apr 2020

PUBLICATION NOTICE: Alabama Barrier Island Restoration Assessment Life-Cycle Structure Response Modeling

Abstract: Dauphin Island, a barrier island off the coast of Alabama, plays an important role in the protection of the state’s coastal natural resources. In 2011, the State of Alabama constructed a rubble mound berm across a 2 km breach in the western end of the barrier island to prevent oil from the Deep Water Horizon oil spill from migrating into the Mississippi Sound. The breach, referred to as the Katrina Cut, was caused by Hurricane Katrina in 2005. The US Army Corps of Engineers and the US Geological Survey (USGS) performed the Alabama Barrier Island Restoration Assessment study to assess the current and future function of Dauphin Island and evaluate potential restoration measures. A Monte Carlo life-cycle structure response assessment of the Katrina Cut rubble mound structure was performed as part of this study by the US Army Engineer Research and Development Center, Coastal and Hydraulics Laboratory. Damage, wave transmission, and reliability were computed within the context of the decadal barrier evolution analysis performed by the USGS for various storminess and relative sea level change scenarios. The presence of a beach in front of the structure plays an important role in its protection. The breaching potential for measures was evaluated.

28 Apr 2020

PUBLICATION NOTICE: Feasibility Investigation of Inductive Heating of Asphalt Repair Materials

Abstract: Airfield pavement repairs conducted as part of rapid airfield damage recovery (RADR) activities must utilize suitable materials to reduce the need for subsequent repairs in order to maintain an operable pavement surface. For asphalt concrete pavements, hot mix asphalt (HMA) is typically used, but this requires a fairly large operation and is less practical for small repairs (e.g., small munitions damage, potholes). Instead, cold mix asphalt (CMA) is typically used for small repairs; however, its performance under aircraft loads is generally unacceptable.  The objective of this project was to investigate the feasibility of rapidly heating small-repair quantities (e.g., 5 gal buckets) of asphalt mix to hot mix temperatures in a matter of minutes. This objective was met using 15% steel aggregate by volume to produce an inductive HMA (iHMA) that could be heated from ambient to 320°F in approximately 5 min. This technology was demonstrated at full scale with a prototype field induction heater; iHMA patch repairs were subjected to simulated F-15E traffic and exhibited comparable rutting resistance to conventional HMA, which was considerably improved relative to CMA. Overall, iHMA was found to be a feasible repair material and should be considered for additional refinement and eventual implementation.