U.S. Army Corps Of Engineers Research Articles

Coastal Processes and the Development of Shoreline Erosion

In 1971 the US Army Corps of Engineers inventoried the stability of the nation's coastlines, concluding in their final summary, A Report on the National Shoreline Study, that of the 135,000 km of coastline, some 33,000 km were seriously eroding. More recently, Dolan et al (1983) assembled the existing data on shoreline changes for the United States, reaffirming the magnitude of this problem. Although such inventories have not been undertaken for the entire world's shorelines, coastal erosion is undoubtedly a global problem. Beach erosion is for the most part episodic, with the major retreats in the shoreline occurring during unusually intense storms. On the east coast of the United States, beach erosion and property losses are produced by nor'easters and hurricanes; on the west coast, intense storms move down from the Gulf of Alaska, generating waves that attack the coastline. This obvious association of beach erosion with the energy level of storm waves creates an oversimplified impression of the actual physical processes involved in the erosion. Only recently have we begun to understand and appreciatc the diversity of processes that are actually involved in coastal erosion. It is now recognized that long-period oscillations may dominate water motions in the nearshore, sometimes containing more energy than the storm-generated waves. These oscillations, as well as a variety of nearshore currents, rearrange the beach sand to cause highly variable rates of shoreline retreat along even short stretches of beach. Although the long­ term rise in sea level has been recognized as an important factor in shoreline

Assessing the control systems available

This paper from the US Army Corps of Engineers’ Construction Engineering Research Laboratory (CERL) reports on the measured performance of pneumatic controls used for heating and air conditioning, giving the advantages and drawbacks of pneumatic, electronic and digital control. Simulating the effect of different control strategies on energy comsumption reveals greater variations than normally assumed. The report finally recommends the use of high quality electronic controllers coupled through transducers to pneumatic valve and damper actuators. For this, CERL has devised a reliable control panel which gives quick diagnosis of performance; it can be retrofitted as part of a simple control for variable air volume systems.

Corps of Engineers Develops Water Supply Tools

The US Army Corps of Engineers has available a number of up‐to‐date publications that could assist water utilities and engineers with planning, design, and operational problems. The author includes a list of reports and manuals applicable to the drinking water industry.

Monitoring total suspended solids by using nephelometry

Correlation curves were developed relating nephelometric turbidity units (NTU) with total suspended solids (TSS) for diked upland dredged material placement site effluents of three US Army Corps of Engineers (COE) maintenance dredging projects in the Chesapeake Bay, Maryland. The procedure was developed in an effort to ensure compliance with Maryland's 400 milligrams per liter (mg/l) TSS standard for COE dredging projects. Samples of the sediments to be dredged were collected and analyzed, correlating turbidity readings with TSS determined by standard gravimetric techniques. The correlation curves were provided to the COE inspectors to measure the effluent with a turbidity meter and to extract a TSS concentration from the correlation curve. Samples collected and analyzed after initiation of the dredging indicated that the correlation curves were an overestimate of the actual TSS concentrations of the effluent discharges. The procedure, endorsed by the State of Maryland, provided immediate on-site TSS analysis eliminating the previously encountered delays in obtaining gravimetric analysis of effluent discharges and potential contract management problems.

Preparing specifications by computer

A marked increase in accuracy and efficiency has been achieved by the US Army Corps of Engineers with a computerised system for preparing specifications for its construction projects. Known as ‘Editspec’, the system simplifies the selection of design conditions taken from master guides, allows for updating or specification changes and finally automatically prints out the correct specification text for the complete project. Its operation is explained here by a member of the US Construction Egineering Research Laboratory, which devised the system.

Prototype integrated building model

This paper describes an integrated database facility model called CAEADS, now being developed for the US Army Corps of Engineers. The function of the facility model is to accept and store a description of any conventional building design in a structure so as to allow automatic preparation of data for a number of applications. Later stages of development will include a full design entry system and capabilities for production document preparation.

The United States Army Corps of Engineers: Two Centuries of Interdisciplinary Engineering

For over 200 years, since its foundation in 1775, the US Army Corps of Engineers has undertaken a vast variety of civil, in addition to its military, engineering tasks. Undoubtedly its most important has been, and continues to be, the construction of dams, the flood control, the bridging and the provision of locks for the American Continent's immense inland water resources, especially the Mississippi River. Other achievements, like the Apollo's Vehicle Assembly Building, the historical survey of the unexplored West, disaster relief and civil engineering works in Arabian countries, are relatively unknown, but here illustrated.

The United States Army Corps of Engineers: Two Centuries of Interdisciplinary Engineering

AbstractFor over 200 years, since its foundation in 1775, the US Army Corps of Engineers has undertaken a vast variety of civil, in addition to its military, engineering tasks. Undoubtedly its most important has been, and continues to be, the construction of dams, the flood control, the bridging and the provision of locks for the American Continent's immense inland water resources, especially the Mississippi River. Other achievements, like the Apollo's Vehicle Assembly Building, the historical survey of the unexplored West, disaster relief and civil engineering works in Arabian countries, are relatively unknown, but here illustrated.

The Mid-Atlantic Engineers: A History of the Baltimore District, U.S. Army Corps of Engineers, 1774-1974.

Abstract : The US Army Corps of Engineers has played a vital role in the development of our nation, dating back to the Revolutionary War. In fact the first known Corps project in the Baltimore area was the building of Fort McHenry. No one at the time could predict just how successful this project would be, but historians have recorded the fierce bombardment of Fort McHenry by the British during the War of 1812. Fort McHenry saved the city of Baltimore. The stirring account of the battle by Francis Scott Key, who was on board a British ship trying to arrange the release of an American prisoner of war, was written down in verses of The Star Spangled Banner. Though much of the early Corps work in the Maryland area was for national defense, Corps personnel also assisted in private and public efforts to develop the nation's transportation system in this area. The assistance of Army engineers in construction of communications networks in the Maryland area roads, railroads, canals, and navigation channels-was an important influence on the economic development of the state. Throughout the years the Corps has performed military construction, been assigned responsibility for water navigation, flood control, water resources management, and the unique mission of providing drinking water for the city of Washington, DC. The Baltimore District, with an illustrious record of past accomplishments, looks to future opportunities to serve our nation.

WATER QUALITY EFFECTS OF LEACHING FROM SUBMERGED SOILS

To implement the proposed impoundment of the Northeast Cape Fear River in Dulpin County, North Carolina, the US Army Corps of Engineers asked the Federal Water Pollution Control Administration to investigate the leaching of undesirable materials into the impounded waters. Since the impoundment will inundate an area with rich organic soils, the possibility of leaching is high, and this research is important to the future of the whole project.

Distinguishing Ambient And Anthropogenic Sediments At SensitiveCoastal Ocean Sites

2 Jacksonville District, US Army Corps of Engineers, USA Abstract Often during dredging, beach renourishment, or other coastal engineering activities, questions arise as to whether those activities are causing unintended, unexpected, deleterious environmental impacts. A typical question arising during dredged material disposal operations in a coastal zone, is whether any of the discharged dredged material is being transported out of the designated disposal site to a sensitive coastal ocean site of concern. In Florida (USA), and in the Caribbean, a sensitive coastal ocean site of concern is typically a coral reef location. In dredging operations in Ft Pierce Florida, local citizens expressed concern about a muck- like substance, observed covering a coral site, and wondered if it originated from the designated dredged-material disposal site, Proni (l). To address this concern a long term monitoring program has been undertaken to determine the following: 1) what other potential sources, besides the discharged dredged material, of the muck- like material may exist, Trefry (2), 2) what are the biological, chemical and sedimentary characteristics of the material, 3) do any of the other potential sources of material have similar characteristics, 4) do oceanographic and meteorological conditions favor the transport of dredged material from the disposal site to coastal site(s) of concern and, 5) what is the chronological history of the appearance of muck-like material at the site of concern? In this paper a discussion of results obtained to date is presented. Potential other sources of the material are identified and discussed, which include upwelled Atlantic ocean water, flood control releases from canals and bays, and dredging site transport (in contrast to transport from the dredged-material disposal site). Oceanic current observations are presented together with a discussion of potential sediment transport pathways. Potential effects of meteorological phenomena on coastal sediments are also discussed. Statistical cluster analysis of biological parameters suggests an ability to distinguish dredging site related organisms from coastal shelf organisms.

Difficulties Associated with Predicting Depth of Freeze or Thaw

Calculations using the Neumann solution (as modified by Aldrich) and thermal properties of soils (obtained by Kersten) show that the frost penetration depth for the same freezing index for essentially all soils with any moisture content and for dry sand and rock varies by a factor of about 2 to 1. The extremes calculated in this way bracket the experimentally determined design curve of the US Army Corps of Engineers and give it theoretical support. The theoretical calculations and additional experimental data are used as a basis for a small alteration in the slope of the design curve. This modified design curve is recommended for field use because of (1) inherent imperfections in existing theory and (2) practical limitations to precise specification of field conditions.

Electrodialytic Demineralization at Gettysburg Air Force Station

For approximately four years after completion of Gettysburg Air Force Station in 1955, personnel assigned there shunned consumption of the water supply because of its unusually high salt content. In 1959, an electrodialysis water demineralization plant was put into operation which caused these residents to switch from bottled beverages to water. This was the first plant of its type to be constructed in the midwest. Design and construction was under the direction of the US Army Corps of Engineers, Omaha District Office, Omaha, Nebraska. This article presents general design considerations and operational data from over three years of operation.

Russian River Channel Works

Evaluations of channel stabilization works constructed in 1956 by US Army Corps of Engineers, along 4 mi test reach of Russian River near Geyserville, Calif; from observations of this work, tentative conclusions are reached that works performed could be adapted, if approved, to design of other reaches of Russian River.