Shear models and parametric analysis of the PVC geomembrane-cushion interface in a high rock-fill dam

PLoS One. 2021 Jan 22;16(1):e0245245. doi: 10.1371/journal.pone.0245245. eCollection 2021.

Abstract

As a type of flexible impermeable material, a PVC geomembrane must be cooperatively used with cushion materials. The contact interface between a PVC geomembrane and cushion easily loses stability. In this present paper, we analyzed the shear models and parameters of the interface to study the stability. Two different cushion materials were used: the common extrusion sidewall and non-fines concrete. To simulate real working conditions, flexible silicone cushions were added under the loading plates to simulate hydraulic pressure loading, and the loading effect of flexible silicone cushions was demonstrated by measuring the actual contact areas under different normal pressures between the geomembrane and cushion using the thin-film pressure sensor. According to elastomer shear stress, there are two main types of shear stress between the PVC geomembrane and the cushion: viscous shear stress and hysteresis shear stress. The viscous shear stress between the geomembrane and the cement grout was measured using a dry, smooth concrete sample, then the precise formula parameters of the viscous shear stress and viscous friction coefficient were obtained. The hysteresis shear stress between the geomembrane and the cushion was calculated by subtracting the viscous shear stress from the total shear stress. The formula parameters of the hysteresis shear stress and hysteresis friction coefficient were calculated. The three-dimensional box-counting dimensions of the cushion surface were calculated, and the formula parameters of the hysteresis friction were positively correlated with the three-dimensional box dimensions.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Computer Simulation
  • Equipment Design
  • Particle Size
  • Polyvinyl Chloride / chemistry
  • Pressure
  • Shear Strength*
  • Silicones / chemistry
  • Surface Properties
  • Viscosity

Substances

  • Silicones
  • Polyvinyl Chloride

Grants and funding

The present research was financially funded by the Postgraduate Research & Practice Innovation Program of Jiangsu Province (No. KYCX17_0440) to YFL, the Fundamental Research Funds for the Central Universities (No. 2017B626X14) to YFL, the National Natural Science Foundation of China (No. 51379069) to YMS, the Youth Science Foundation of Jiangxi Province (No. 20192BAB216039) to XXL, the Scientific Research Foundation of Jiangxi Provincial Education Department(No. GJJ191093) to XXL. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.