Predicting Soil-Water Retention Functions of Hanford Soils From Particle Size Distribution Data. (4571)
Authors:
J.M. Keller* - Battelle, PNNL A.L. Ward - Battelle, PNNL Z.F. Zhang - Battelle, PNNL G.W. Gee - Battelle, PNNL
Abstract:
Field-scale transport predictions require upscaled hydraulic properties. The
Arya-Paris (AP) model can be used to predict properties for natural soils from the particle size distribution but requires a fitting parameter, alpha, to account for deviations between ideal and natural soils. Using four independent soils, alpha is calculated by scaling the AP predicted water retention curves to lab- and
field-measured curves and to field-scale curves obtained by inverse modeling of infiltration tests. A saturation dependent alpha is calculated for the lab and field curves and the effect of observation scale explored. For all soils alpha is dependent on saturation and decreases as the scale of measurement increases. The scale dependence is consistent with an increase in effective pore radius at a given
moisture content as the observation scale increases. The scaling relationships can be used to predict field-scale hydraulic properties from AP predicted or lab-measured water retention functions. The Pacific Northwest National Laboratory is operated for the U.S. Department of Energy by Battelle under Contract
DE-AC06-76RL01830.
Speaker Information: Jason Keller, Battelle, PNNL, PO Box 999K9-36, Richland, WA 99352; Phone: 5093753875; E-mail: [email protected]
Session Information: Wednesday, November 3, 2004, 4:00 PM-6:00 PM Presentation Start: 4:00 PM (Poster Board Number: 2710)
Keywords: Arya-Paris Model; Measurement Scale; Particle Size Distribution; Soil Water Characteristic
