JOURNAL OF ROCK MECHANICS

JOURNAL OF ROCK MECHANICS

The Effect of Strength Parameters of Rock Joints on the Scoure Intensity of Stilling Basin behind a Dam

Document Type : Original Article

Authors
Seyed Mosleh Eftekhari 1
Alireza Baghbanan 2
Anahid Ghamari mood 2
1 Faculty of Engineering, Tarbiat Modares University, Tehran, Iran.
2 Department of Mining Engineering, Isfahan University of Technology (IUT), Isfahan, Iran.
10.22034/IRSRM.2023.2125522
Abstract
One of the ways to investigate the scouring phenomenon is by numerical investigation. The conventional software used in this field does not have the ability to model the rock mass, therefore, in this research, the impact of the resistance parameters of the rock mass on the erosion of the calm pond behind the dam has been analyzed. For this purpose, calculations related to the fluid have been done using FLOW-3D software. Then the appropriate output from this software has been extracted and further analysis has been done in the UDEC discrete element software. The results show the profound effect of these parameters on the shape and amount of scouring. In such a way increasing the amount of adhesion and the internal friction angle of the joints reduces the depth and width of the critical scour and also its extent. However, the severity of their impact on reducing the depth and width of critical scour and its extent is not the same. In the following, some equations are proposed to predict scour depth and width.
Keywords
Scour
Stilling basin
Free overflow
Strength parameters
Discrete element method
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JOURNAL OF ROCK MECHANICS
Volume 7, Issue 1
Spring 2023
Pages 1-21