UDEC modelling

SRK uses Universal Distinct Element Code modelling to understand pit slope stability in China.

The Universal Distinct Element Code (UDEC), developed by the ITASCA Consulting Group, is a “distinctive element program for discontinuum modelling”. UDEC simulates the response of discontinuous media (different rock types) when they are subjected to either static or dynamic loading. Linear or non-linear force-displacement causes movement in both normal and shear directions.

SRK used UDEC modelling on part of the east pit of a gold mine in western China to gain a better understanding of the mechanical behavior of the rocks in the two main joint sets encountered in the east wall, when the upper pit is excavated sequentially, and to provide a basis for the design of the final pit.

Two cases were modelled:

• Model 1: Includes only one set, 1m continuous
• Model 2: Includes both sets, 1m continuous and 4m discontinuous

It was assumed that the horizontal and vertical stresses are equal and are caused purely by their own weight. A strength reduction technique was used to evaluate the factor of safety (FOS). The material strength was reduced to a level where the pit becomes unstable and failure develops. Figure 1 shows the point where the slope becomes unstable, providing clues to the likely mechanical behavior of the pit walls as the pit is gradually deepened.

Yonglian Sun: ysun@srk.cn

You can download a PDF of the entire
Focus on Rock Engineering and
Slope Stability newsletter 





Our newsletters focus on specific areas of interest to earth resource professionals and clients. Each is available as an Adobe Acrobat PDF file. If you don't already have Adobe's PDF reader, you can download it free.

SRK Turkey