A Theory of Porous Plasticity at Low Triaxiality
A simple multiaxial theory of plasticity which is capable of taking into account the influence of pore shape at low concentration is developed for an isotropic porous material at a triaxiality...
On Determination of Turbulence Model Coefficients for Anisotropic Reynolds Stress Closure Model
In this paper, the determination of turbulence model coefficients for anisotropic Reynolds stress model is discussed. The proposed model includes anisotropic Reynolds stress modeling and...
Observations of Microcracking and Pore Collapse in Limestone Using Liquid Metal Porosimetry
A technique has been developed to preserve and observe the microstructure of rock or other porous material, as they exist under stresses, using liquid metal porosimetry. Cylindrical specimens...
Moisture Diffusion in Concrete and Mechanisms of Drying Creep
The Pickett effect is the excess of creep at drying over the sum of shrinkage and basic creep. Several theoretical models have been presented to speculate on the mechanisms of this effect,...
A Piston-Type Nonlinear Wavemaker Theory
In this paper, the small-amplitude surface waves produced by a piston-type nonlinear porous wavemaker in an infinitely and a semi-infinitely long channel are studied. Analytical solution...
Visualization Studies of Dense Leachate Plumes in Porous Media
In this paper, a series of flow visualization experiments investigating the behavior of dense leachate plumes are described. These experiments were performed in various flow containers...
Field Verification of Diffuser Performance
Effluent diffusers are used to gain relief from end-of-pipe acute toxicity criteria in NPDES water quality-based discharge permitting. Regulatory agencies require that the dilution provided...
Temperature Rise, Bank Erosion, and Jet Velocity Effects of Submerged Multiport Diffusers in an Estuary
Temperature distributions, potential bank erosion, and jet velocity and trajectory of submerged multiport diffusers were predicted as part of the permitting process for an fossil fuel...
Diffuser Design for Water Quality-Based Toxics Control
U.S. Environmental Protection Agency regulations require that the discharge of toxic pollutants to the waters of the United States be controlled. These regulatory requirements have made...
Oxygen Transfer in Full Lift Hypolimnetic Aeration Systems
A series of experiments were conducted to examine the effect of diffuser depth, diffuser orifice diameter and separator box surface area on oxygen transfer (mg/L), daily oxygen load (kg...
Diffusion Barrier Transport Properties of Unsaturated Paintbrush Tuff Rubble Backfill
Diffusion coefficients (D) were experimentally determined in unsaturated tuff gravel to evaluated the effectiveness of tuff gravel and rubble as a diffusion barrier to ionic transport...
Diffusion Coefficients and Hydraulic Conductivity in Unsaturated Hanford Soils and Sediments
Two groundwater transport parameters of some Hanford formation materials, the hydraulic conductivity and the diffusion coefficient, were measured to aid in predicting contaminant migration....
Computation of Unsaturated Soil Parameters Using Upward Infiltration Empirical Data
The relationship between soil moisture content and hydraulic conductivity with the soil tension be defined to simulate unsaturated flow in a porous media. Direct measurements of these...
Bottom Plugging Dynamics in Recharge Basins
The Orange County Water District is investigating the reasons why percolation rates in deep recharge basins rapidly decrease. The interrelationship between microbiological activities in...
Application of the U.S.G.S. DHM for Floodplain Analysis
The two-dimensional Diffusion Hydrodynamic Model, DHM, is applied to the evaluation of floodplain depths resulting from an overflow of a leveed river. The environmental concerns of flood...
Thermal Plumes from Staged Diffusers into a Uniform Quiescent Environment
The behavior of thermal plumes from staged multiport diffusers was investigated experimentally. The three-dimensional temperature distribution was measured by scanning thermistor rakes...
CORMIX2: Expert System for Multiport Diffuser Discharges
The Cornell Mixing Zone Expert System (CORMIX) is a series of software systems for the analysis, prediction, and design of aqueous toxic or conventional pollutant discharges into watercourses,...
Solving Turbulent Flows with Finite Elements
A finite element computer code using the q - r turbulence model is applied to turbulent flow under a sluice gate. The addition and slow removal of artificial diffusion enhances convergence....
Practical Prediction of Concrete Shrinkage and its Uncertainty
An improved prediction model for shrinkage is proposed. The main features are (1) diffusion-type size dependence for humidity effects, (2) initial and final asymptotic forms of the shrinkage...
Environmental Degradation of Concrete Pore Structure
This paper illustrates how Conductometric Phase Transition Porosimetry can be used to monitor changes in the pore structure of Portland Cement Concrete which result from repeated freezing...
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