Stable Channels with Loose Boundary
Recently, G. Parker suggested that the lateral transport of downstream momentum due to Reynolds stresses should be included in the momentum balance used to calculate the boundary shear...

A Lawyer's View of Engineers' Responsibility
When presented with a case involving damaged property, a lawyer typically will seek to determine the point of the failure and then work backwards in an effort to analyze each of the factors...

Near-Bed Sediment Concentration in Non-Uniform Flows Over Gravel Beds
The calculation of near-bed sediment concentration is formulated in terms of equations governing the dispersion of heavy particles in non-uniform turbulent shear flows over stable gravel...

Analytical and Numerical Modeling at High Sediment Concentrations
Methods for classifying sediment-water mixtures according to material concentration and rheologic properties are discussed. Results from laboratory and field measurements show that bed...

Entrainment of Bed Sediment by Density Underflows
The erosion caused by a density-driven underflow has been studied experimentally. The observations indicate that a strong density current can entrain substantial amounts of bed sediment....

Ultimate Sediment Concentration
The sediment rating curve is used to relate sediment discharge to water discharge, under steady equilibrium flow conditions. The slope of the sediment rating curve is a measure of the...

Effectiveness of Spur Dike Notching
The most widely used technique of ameliorating the environmental effects of river-training works has been to construct notches in spur dikes (or to allow notches to remain in damaged dikes)...

Snow-Melt Triggered Debris Flows Affecting Utah's Megalopolis
During the abnormally wet years of 1983 and 1984, debris flows were triggered late in spring on the west flank of the Wasatch Mountains and elsewhere in Central Utah. These debris flows...

Analysis of Onsite Measurements of Scour at Piers
Existing onsite measurements of local scour at bridge piers were assembled and analyzed to obtain an equation that predicts the expected maximum depth of local scour at a bridge pier....

Prediction of Scour Depth Under Armoring Conditions
A simple procedure is proposed to compute scour depth on an alluvial bed having graded materials under flow conditions which produce armor layer at the bed surface. The procedure is based...

The Effects of Sediment Transportation Changes on Aquatic Habitat
Sediments are a natural part of the riverine and estuarine environment. However, if the sediment load changes or bed sediment type occur, direct and sometimes detrimental and sometimes...

Estimation of Uplift Pressure in Cracks in Concrete Gravity Dams
This paper presents an analytical solution to predict uplift pressures in cracks in concrete gravity dams. It is shown that drainage systems are effective in reducing such pressures....

Design and Performance of Earth Spillways
The U.S. Department of Agriculture's Soil Conservation Service has designed and administered construction of a large number of dams utilizing grassed earth-lined auxiliary...

Identification of Automation Opportunities
Construction, although the world's largest industry, is also its most archaic. Most construction practices are very labor-intensive, with resulting impacts on safety, productivity,...

Terrestrial Trends for Building Technology in North America
This paper discusses new building technologies that will develop in the early 1990's to become significant technologies by the mid 1990's. The perspective is...

Constraints on Lunar Base Construction
This article discusses the development of scenarios and designs for the construction of a lunar base or network of bases, which will require close attention to the natural and human constraints...

Lunar Resources: What is Known and Expected
The lunar regolith is the source of a number of basic materials which can be utilized in lunar construction. These materials include those which are obtained directly from the regolith...

Environmental Considerations for Lunar Base Engineering
Currently a large number of conceptual designs are being offered for the lunar base involving various types of structural materials and equipment for construction or resource recovery....

Generation of Native FE in Lunar Soil
Electron Spin Resonance (ESR) studies on lunar samples produced some unexpected results which led to recognition of the presence of abundant single-domain Feo...

Hot Pressing of Lunar Soil and Qualification for Manned Applications
Lunar soil may be fabricated into useful building materials analogous to those used for masonry, concrete and ceramic pipe applications on earth. The process has been analyzed theoretically...

 

 

 

 

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