20 Mar 2023

Numerical Modeling of Supercritical Flow in the Los Angeles River: Part I: Adaptive Hydraulics Numerical Modeling of the 1943 Physical Model

Abstract: The Los Angeles District of the US Army Corps of Engineers is assisting the City of Los Angeles with restoration efforts on the Los Angeles River. The city wishes to restore portions of the channelized river to a more natural state with riparian/vegetative green spaces for both wildlife and public recreation usage. The Los Angeles River provides an important role for the City of Los Angeles from a flood-control perspective, and functionality needs to be preserved when contemplating system modifications. This report details the development of an Adaptive Hydraulics (AdH) numerical model capable of representing this complex system consisting of both subcritical and supercritical flow regimes. Due to limited hydraulic data in the study area, an extensive model validation to observed data was not possible. To bridge the data gap, a numerical model was developed from a previously completed physical model study with extensive quantitative measurements and qualitative reports of hydraulic conditions. This approach allowed engineers to evaluate the effectiveness of the AdH model in representing this complex hydraulic system along with determining the best methodology to accurately represent the existing conditions. This study determined appropriate model parameters that will be utilized in further numerical modeling efforts to evaluate system modifications associated with restoration efforts.

20 Mar 2023

Old River Control Complex (ORCC) Low Sill: A Literature Synthesis

Abstract: The US Army Corps of Engineers (USACE), New Orleans District (MVN), tasked the US Army Engineer and Research Development Center (ERDC) with assessing the condition of a grouted scour hole located at the southeast wall of the Old River Low Sill Structure (ORLSS) at the Old River Control Complex (ORCC) using noninvasive techniques, such as geophysical surveys and physical models. This special report (SR) combines a scientific literature synthesis of previous research with further geologic interpretation as a first step in the overall task assigned by MVN. The results discussed in this SR will be used to inform the interpretation of geophysical surveys, construction of physical models, and input for the slope stability analyses.

15 Mar 2023

Underwater Carbon Fiber–Reinforced Polymer (CFRP)–Retrofitted Steel Hydraulic Structures (SHS) Fatigue Cracks

Purpose: Recent advances in the use of fiber-reinforced polymers (FRP) to retrofit steel structures subjected to fatigue cracks have shown to be a viable solution for increasing fatigue life in steel hydraulic structures (SHS). Although several studies have been conducted to evaluate the use of FRP for retrofitting metal alloys and the promising potential of such has been well-demonstrated, the application has never been implemented in underwater steel structures. This Coastal and Hydraulics Engineering Technical Note presents the implementation of FRP patches to repair fatigue cracks at Old Hickory Lock and Dam miter gate.

15 Mar 2023

Suggested Updates for the Inclusion of Guidance on Ultra-High Performance Concrete to USACE Engineering Manual 1110-2-2000, Standard Practice for Concrete for Civil Works Structures

Abstract: Ultra-high performance concrete (UHPC) is a relatively modern class of concrete with properties that include very high compressive strengths, increased tensile strengths, very low permeability, and superior durability compared to conventional, normal-strength concrete. As research of this material continues to progress, its applications under both military and civil works categories expand. However, mixture and structural design guidance using UHPC is limited, particularly in the United States. This special report provides an overview of UHPC as initial guidance for the US Army Corps of Engineers (USACE) so that the material may be more easily utilized in civil works infrastructure. The information contained in this report is based on years of experience researching and developing UHPC at the US Army Engineer Research and Development Center (ERDC) and is intended to be a basis for the incorporation of this material class into USACE Engineer Manual (EM) 1110-2-2000, Standard Practice for Concrete for Civil Works Structures, when it is next updated.

13 Mar 2023

Assessment of LEED 2.2 and LEED 2009 Implementation in Meeting Army SDD Policy Goals

Abstract: This report describes our analysis of how Army Leadership in Energy and Environmental Design (LEED®) certification data demonstrates success in meeting Army sustainable design and development (SDD) policy goals. Specifically, the research team evaluated how LEED 2.2 and v2009 credits related to Army SDD policy objectives, then identified trends over time in Army LEED 2.2 and v2009-rated Projects. This is a historical assessment of actual project data, captured before the Army transitioned to the newer LEED v4. This report explains how implementation of LEED NC 2.2 and v2009 credits helped Army projects achieve SDD policy objectives. Emphasis was placed on LEED credits that directly related to SDD policy requirements which Army construction and major renovation projects needed to meet. Figures throughout the report illustrate how many Army LEED certified projects earned LEED New Construction credits 2.2 from FY2009 to FY2016 and LEED v2009 credits from FY2011 to FY2016. Some figures also rank the LEED 2.2 and LEED v2009 credits from most popular to least popular. Implementation of the Army’s 2013 SDD policy requiring LEED certification has allowed analysis of how Army military construction (MILCON) projects achieved energy, water, and waste goals on a large scale.

13 Mar 2023

Safe and Rapid Development of Advanced Materials: A Research Case Study for Safe Development of Nanoenabled Environmental Sensors

Abstract: The enhanced understanding of nanomaterials properties and processing has led to increased use of nanotechnologies, which has also led to greater scrutiny on the commercialization and acquisition of emerging nanoenabled technologies. Caused by knowledge gaps on the unique behaviors, risks, and liabilities of novel engineered nanomaterials, this caution, when not evidence based, slows production and stifles innovation. Reducing the uncertainty surrounding the environmental risks and benefits of nanoenabled technologies, including their resilience in harsh environments, will speed the development and transition of advanced material technologies. In this work, a multifaceted research program generated data and processes to reduce that environmental uncertainty. Specifically, this case study examined printed, nanoenabled environmental sensors and their components to develop toxicological data and parameterize a life-cycle assessment. The study tested the sensors’ resilience in environmental weathering studies that considered both the potential release of the ingredient nanomaterials and the performance of the sensors after exposure to several harsh environmental climates and then created life-cycle inventories to determine environmental impact and reduce cost of research and development. Finally, this case study developed software tools to mitigate the cost of research and provide a framework for presenting toxicology data.

9 Mar 2023

Automatic Identification System (AIS) Data Case Study: Vessel Traffic through the Yaquina Bay Breakwater at Newport, Oregon

Abstract: The navigation staff at US Army Corps of Engineers (USACE) Portland District (NWP) asked for information on vessel transits through the two existing openings in the breakwater on the north side of Yaquina Bay in Newport, Oregon. Currently, no authorized federal channel passes through the breakwater openings; however, the design for a possible federal channel is under consideration. NWP staff were interested in historical vessel transits, with a special focus on isolating transits for the largest (i.e., longest) vessels, identified as vessels 80 feet or longer, currently utilizing the area inside the breakwater. The Automatic Identification System Analysis Package (AISAP) software created by USACE-ERDC (2018) was used to analyze vessel traffic.

8 Mar 2023

A Large-Scale Community Storm Processes Field Experiment: The During Nearshore Event Experiment (DUNEX) Overview Reference Report

Abstract: The DUring Nearshore Event EXperiment (DUNEX) was a series of large-scale nearshore coastal field experiments focused on during-storm, nearshore coastal processes. The experiments were conducted on the North Carolina coast by a multidisciplinary group of over 30 research scientists from 2019 to 2021. The overarching goal of DUNEX was to collaboratively gather information to improve understanding of the interactions of coastal water levels, waves, and flows, beach and dune evolution, soil behavior, vegetation, and groundwater during major coastal storms that affect infrastructure, habitats, and communities. In the short term, these high-quality field measurements will lead to better understanding of during-storm processes, impacts and post-storm recovery and will enhance US academic coastal research programs. Longer-term, DUNEX data and outcomes will improve understanding and prediction of extreme event physical processes and impacts, validate coastal processes numerical models, and improve coastal resilience strategies and communication methods for coastal communities impacted by storms. This report focuses on the planning and preparation required to conduct a large-scale field experiment, the collaboration amongst researchers, and lessons learned. The value of a large-scale experiment focused on storm processes and impacts begins with the scientific gains from the data collected, which will be available and used for decades to come.

23 Feb 2023

AIS Data: An Overview of Free Sources

Abstract: The purpose of this Coastal and Hydraulics Engineering technical note (CHETN) is to describe the sources of Automatic Identification System (AIS) data available to the public, with a focus on federal employees who may need AIS data to carry out their official duties. AIS data, in this context, refer to both real-time and historic vessel position information.

22 Feb 2023

USACE R&D FY22 Annual Report

Abstract: This annual report has been compiled to meet our Commanding General’s intent to better “tell the story” of the innovative R&D being conducted by USACE, and specifically the U.S. Army Engineer Research and Development Center, to support the nation and assist USACE in meeting its R&D missions in the areas of Civil Works, Warfighter Support, Installations and Operational Environments, and Support for Others.