Effect of Material Heterogeneities on Flow Through Porous Media
Modeling studies were conducted to determine the effects of material heterogeneities on the flow of water through rock. Multiple numerical calculations were made using random variations...
Theory of Matrix and Fracture Flow Regimes in Unsaturated, Fractured Porous Media
The flow behavior of a two-dimensional, unsaturated fracture-matrix system is characterized by a critical flux qf*...
An Alternative Method to Mariotte Reservoir System for Maintaining Constant Hydraulic Pressure
Several problems with the Mariotte reservoir system were discovered when it was used to apply a constant water pressure as a boundary condition for a prolonged period. The constant-pressure...
Near-Field Transport of Radioactive Chains
Much attention has been given to predicting the near-field mass transfer of a single radioactive species from a waste solid into surrounding porous material, but only limited consideration...
Apparent and Simple Diffusion Coefficients in Compacted Bentonite
Diffusion coefficients were experimentally determined in bentonite to evaluate the effectiveness of bentonite layers as a diffusion barrier to ionic transport away from high-level radioactive...
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...
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...
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 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...
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...
Chloride Diffusion Constant for Concretes
Reinforced concrete exposed to chloride ions rapidly deteriorates once the chloride concentration level exceeds the corrosion threshold limit. The diffusion of the chloride ion through...
Weighted Finite Difference Method for Diffusive Transport
The purpose of the paper is to present an application of a new method to the two-dimensional, transient advective-diffusive transport in both turbulent flow of viscous fluid and seepage...
Underdrain Tube Wall, Perforation Design and OBPA to Minimize Bio-Chemical Clogging
Bio-chemical clogging of underdrains has been most frequently associated with iron deposits (ochre). The underlying sticking agents have been a variety of bacteria and their exudates commonly...
Bulk Stomatal Resistance in Operational Estimates of Evapotranspiration
General relationships for estimating canopy or bulk stomatal resistance and aerodynamic resistances of grass and alfalfa reference crops for use in the Penman-J.L. Monteith equation are...
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