A New Modified Model of the Streaming Potential Coupling Coefficient Depends on Structural Parameters of Soil-Rock Mixture

Xin Zhang,Mingjie Zhao,Kui Wang,Xiangjian Dong

doi:10.1155/2021/2619491

Abstract

The streaming potential effect in soil-rock mixture (SRM) is related to the compactness and rock content, but there is no model to quantitatively describe this behavior. In this paper, the Kozeny–Carman (KC) equation is modified by using the compactness and rock content. Then, the modified KC equation is substituted into the equation of streaming potential coupling coefficient. A new modified model of streaming potential coupling coefficient that depends on the compactness, rock content, particle shape, and particle gradation is proposed. The reliability of the new modified model is tested by experiments, and the applicable scope of the model is obtained. The results show that when the rock content is 30%, the permeability coefficient prediction accuracy of the modified KC equation is higher in the range of 85–95% compactness. The new modified model of the streaming potential coupling coefficient represents well the control of the compactness (75–95%) on the coupling coefficient. When the compactness remains 85%, the permeability coefficient calculated by the modified KC equation in the range of 10–70% rock content is consistent with the experimental data. The influence of the rock content (10–90%) on the coupling coefficient is well described by the new modified model of the streaming potential coupling coefficient. The new modified model of streaming potential coupling coefficient is helpful to quantitatively evaluate the internal structure evolution of embankment dam by using streaming potential phenomenon.

Highlights

Embankment dams play an important role in flood control, irrigation, and power generation
The permeability obtained by the modified KC equation is substituted into Equation (2) to calculate the streaming potential coupling coefficient
There is a great difference between measured permeability and predicted permeability at 75–80% compactness and 90% rock content, but the predicted streaming potential coupling coefficient of the new modified model is consistent with the experimental data at different compactness (see Figure 5(a))

Summary

Introduction

Embankment dams play an important role in flood control, irrigation, and power generation. Streaming potential effect is a kind of electrokinetic phenomenon, and the generation process is closely related to the seepage of porous media [1, 2]. It is often used for monitoring of water flow process and has the potential to obtain information on the structure of embankment dams [3]. SRM as filling material of embankment dam and the seepage characteristics of SRM are mainly affected by structural factors such as rock content, compactness, particle shape, and grading curve [4,5,6]; that means the model of streaming potential coupling coefficient of SRM is different from that of rock and soil. The existing streaming potential coupling coefficient model cannot describe the structural characteristics of the SRM

Methods

Results

Discussion

Conclusion