Improved model for predicting the hydraulic conductivity of soils based on the Kozeny–Carman equation

Abstract

The saturated hydraulic conductivity of soils is a critical concept employed in basic calculation in the geotechnical engineering field. The Kozeny–Carman equation, as a well-known relationship between hydraulic conductivity and the properties of soils, is considered to apply to sands but not to clays. To solve this problem, a new formula was established based on Hagen–Poiseuille's law. To explain the influence on the seepage channel surface caused by the interaction of soil particles and partially viscous fluid, the surface area ratio was introduced. A modified framework for determining the hydraulic radius was also proposed. Next, the relationship between the effective void ratio and the total void ratio was established for deriving the correlation of hydraulic conductivity and total void ratio. The improved equation was validated using abundant experimental results from clays, silts, and sands. According to the results, the accuracies of the proposed model with two fitted multipliers for clays, silts, and sands are 94.6, 96.6, and 100%, respectively, but with only one fitted parameter, the accuracies are 97.1, 91.5, and 100%, respectively. The proposed model can be considered to have a satisfactory capability to predict hydraulic conductivity for a wide variety of soils, ranging from clays to sands.

Impact of soil compaction and irrigation practices on salt dynamics in the presence of a saline shallow groundwater: An experimental and modelling study

“…The decrease in soil porosity due to compaction decreases the saturated hydraulic conductivity, K s . The hydraulic conductivity is often difficult to determine because it depends on numerous factors including the particle size distribution, particle shape, porosity, void ratio and clay content (Chapuis, 2004; Kango et al, 2019; Mahmoodlu et al, 2016; Wang et al, 2021). In this study, the hydraulic conductivity was measured for different bulk densities.…”

3–4D soil model as challenge for future soil research: Quantitative soil modeling based on the solid phase

“…These particles will be available for rapid transport during the following event. After particle‐induced changes of pore scale properties, such as surface areas and pore diameter, macroscopic soil hydraulic and solute transport properties can be derived from local scale modeling of the modified pore structure (Köhne et al., 2011; Lucas et al., 2021) using, for example, the Kozeny–Carman approach to determine permeability (e.g., Gackiewicz et al., 2021; Ren et al., 2016; M. Wang et al., 2021). However, the assumption of an equivalent channel for the highly complex soil pore systems may limit this approach.…”

A Capillary Model for Predicting Saturated Hydraulic Conductivity of Ion-Adsorption Rare Earth Ore Based on Improved Kozeny–Carman Equation

“…(1) Equation ( 2) is established based on the assumption that all pores in the ore body are considered effective pores. However, in practice, there are nonconnected pores such as isolated pores, blind pores, and deadend pores [31,32], which are ineffective pores in the seepage process. e result generated from the assumption has a difference from the tested result.…”

“…Ren et al [29,30] gave a theoretical explanation for the failed application of the KC equation in clay and derived a new model by introducing an effective void ratio, which better predicted the hydraulic conductivity of various soils ranging from coarse-grained to fine-grained. Fang et al [31] and Wang et al [32] proposed the concept of effective specific surface area and improved the accuracy of KC equation in clay. In general, the specific surface area can be obtained with some methods including gas adsorption, ethylene glycol monoethyl ether, and methylene blue absorption techniques [33][34][35].…”