Weep hole effect on uplift pressure distribution and hydraulic gradient beneath concrete dams with permeable foundation

Document Type : Technical Report

Authors

Abstract
Seepage flow modeling beneath hydraulic structures on permeable materials is an essential issue that must be considered before construction processes. Because of no detailed studies, followed by inappropriate design some problems such as foundation erosion, seepage and water escape and structure settlement may be occurring. If we couldn’t overcome these problems in designing process, we can utilize a series of auxiliary actions. Some actions for eliminating the piping and reducing the uplift pressure and hydraulic gradient are construction of horizontal apron, cut-off walls and also weep holes. Hence, in this study the effect of the weep hole on uplift pressure and hydraulic gradient has been investigated. For this purpose, the governing equation of flow through porous media has been solved for different setups, by the numerical method of Control Volume. All calculations have been done by the simple and powerful Excel Spreadsheet tools. Results show that, the application of weep hole reduces the uplift pressure and hydraulic gradient. Installation of a weep hole on stilling basin could reduce the cut-off wall depth and this cause a noticeable reduction of project costs. By moving weep hole toward the downstream of stilling basin and getting away from dam toe, its positive impact will be reduced.

Seepage flow modeling beneath hydraulic structures on permeable materials is an essential issue that must be considered before construction processes. Because of no detailed studies, followed by inappropriate design some problems such as foundation erosion, seepage and water escape and structure settlement may be occurring. If we couldn’t overcome these problems in designing process, we can utilize a series of auxiliary actions. Some actions for eliminating the piping and reducing the uplift pressure and hydraulic gradient are construction of horizontal apron, cut-off walls and also weep holes. Hence, in this study the effect of the weep hole on uplift pressure and hydraulic gradient has been investigated. For this purpose, the governing equation of flow through porous media has been solved for different setups, by the numerical method of Control Volume. All calculations have been done by the simple and powerful Excel Spreadsheet tools. Results show that, the application of weep hole reduces the uplift pressure and hydraulic gradient. Installation of a weep hole on stilling basin could reduce the cut-off wall depth and this cause a noticeable reduction of project costs. By moving weep hole toward the downstream of stilling basin and getting away from dam toe, its positive impact will be reduced.

Seepage flow modeling beneath hydraulic structures on permeable materials is an essential issue that must be considered before construction processes. Because of no detailed studies, followed by inappropriate design some problems such as foundation erosion, seepage and water escape and structure settlement may be occurring. If we couldn’t overcome these problems in designing process, we can utilize a series of auxiliary actions. Some actions for eliminating the piping and reducing the uplift pressure and hydraulic gradient are construction of horizontal apron, cut-off walls and also weep holes. Hence, in this study the effect of the weep hole on uplift pressure and hydraulic gradient has been investigated. For this purpose, the governing equation of flow through porous media has been solved for different setups, by the numerical method of Control Volume. All calculations have been done by the simple and powerful Excel Spreadsheet tools. Results show that, the application of weep hole reduces the uplift pressure and hydraulic gradient. Installation of a weep hole on stilling basin could reduce the cut-off wall depth and this cause a noticeable reduction of project costs. By moving weep hole toward the downstream of stilling basin and getting away from dam toe, its positive impact will be reduced.

Seepage flow modeling beneath hydraulic structures on permeable materials is an essential issue that must be considered before construction processes. Because of no detailed studies, followed by inappropriate design some problems such as foundation erosion, seepage and water escape and structure settlement may be occurring. If we couldn’t overcome these problems in designing process, we can utilize a series of auxiliary actions. Some actions for eliminating the piping and reducing the uplift pressure and hydraulic gradient are construction of horizontal apron, cut-off walls and also weep holes. Hence, in this study the effect of the weep hole on uplift pressure and hydraulic gradient has been investigated. For this purpose, the governing equation of flow through porous media has been solved for different setups, by the numerical method of Control Volume. All calculations have been done by the simple and powerful Excel Spreadsheet tools. Results show that, the application of weep hole reduces the uplift pressure and hydraulic gradient. Installation of a weep hole on stilling basin could reduce the cut-off wall depth and this cause a noticeable reduction of project costs. By moving weep hole toward the downstream of stilling basin and getting away from dam toe, its positive impact will be reduced.

Keywords


Volume 9, Issue 3 - Serial Number 18
Autumn 2015
Pages 181-186

  • Receive Date 23 January 2012
  • Revise Date 20 January 2013
  • Accept Date 19 February 2013