Sedimentation simulation model testing for silty soil water infiltration after Hortonian overland flow

Abstract

Infiltration is a complex environmental process by which an aquatic solution i.e. rainwater, irrigation, potentially contaminated with insoluble/dispersed particles, enters the ground under the gravity force or the capillary action in deeper soil layers (percolation). Simple Hortonian compression events (when overflow run exceeds land infiltration capacity and depression storage capacity), silty-dominated topsoil with smooth texture characteristics and coarse-grained soil constituents are simplistically simulated by lab columns, in different settlement modes, e.g. packed/non-packed. In the present manuscript, suspended material, compression model equations were tested over laboratory setup columns by optimizing model fitting curves via nonlinear regression analysis, one of which received the lowest Standard Error of Estimate value, among eight overall evaluated models, an indication of the best fitting model performance of the ongoing soil-water suspension compression. By using multiple linear regression, modifications were made of all eight tested models which are presented herein. The modified models under examination, were structured upon the linear dependence of their parameters on the selected variables: silt-water concentration, inner cylinder diameter and effective porosity. A modified Kang et al. model, proposed to predict soil water compression phenomenon, by setting coefficients of linear dependence on independent variables. A higher applicability is to be achieved, due to the better fitting of the tested field values, after the conclusion of a proper field calibration. Practitioners would be able to implement the findings over certain field engineering applications. The observed settlement response, during soil water compression in packed/non packed column operating modes, is in compliance with the relative bibliography.