ISSN:
1573-1650
Keywords:
Soil hydraulic properties
;
unsaturation
;
parameter estimation
;
cumulative drainages
;
head profiles
Source:
Springer Online Journal Archives 1860-2000
Topics:
Architecture, Civil Engineering, Surveying
,
Geography
Notes:
Abstract This paper proposes a model for determining the parameters given by the closed-form equations of van Genuchten. An objective function is made by the observed data from vertical drainage, and the solutions of optimization show that less computation and more accurate estimates are made as head profiles are taken into account rather than cumulative drainage. Sensitivity analysis of the error vector to parameters interprets this reason. The convergence and stability of solutions are evaluated with different magnitudes of measured errors in the head, and the results show good estimates will be obtained if a sufficient pressure head at the soil bottom is applied. A variable θ k is introduced to avoid the estimations of α and n being affected by the uncertainties of Ks and θ s .
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00429922
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