Swedge 6.0. Now with a Basal Failure Plane and Bench Design. Basal plane, improved water pressure distribution, and more

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2 Swedge 6.0 Now with a Basal Failure Plane and Bench Design Basal plane, improved water pressure distribution, and more Swedge is an easy-to-use analysis tool for evaluating the stability of surface wedges in rock slopes. Historically, wedges were defined by two intersecting joints / discontinuity planes, the slope surface, and an optional tension crack. In Swedge 6.0, users have the option of including a basal plane, allowing for a wider range of wedge geometries to be considered. Deterministic, Probabilistic, Combination, Sensitivity, and Persistence analysis types are available. For support, bolts, shotcrete or support pressure can be applied. Forces that can be applied include external forces, water pressure, and seismic load. The following are some of the new features included in the upgrade to Swedge 6.0: More Units options Optional Basal Joint Design Factor of Safety (Probabilistic and Combination Analyses) Design Standards Failure Mode Filter More Water Pressure options Bench Design For a complete list of What s New in Swedge 6.0 click here or see the last page in this article.

3 Enhanced Units Options Swedge 6.0 offers a number of new Units options, selected by choosing the unit of stress measurement. There are now three Metric and three Imperial unit options to choose from. The default unit convention is Metric, stress as MPa. Optional Basal Joint In previous versions of Swedge, wedges were formed by only two intersecting joint planes. The intersection of the two joint planes with the 2 slope surface planes (slope face and upper face) formed tetrahedral (4-sided) wedges. New Units options in Project Settings of Swedge 6.0 The new Basal Joint option in Swedge 6.0 allows you to define an optional third sliding joint plane. With the Basal Joint option, complex pentahedral (5-sided) wedges can be considered. In Swedge 6.0, the basal joint is typically a failure plane whose orientation is closer to the horizontal, and the dip direction of the basal plane is typically close to the dip direction of the slope. In a basal joint analysis, it is possible for socket wedges to form. A socket wedge is a wedge whose joint planes do not intersect the slope crest. Users have the option to include or exclude socket wedges in the analysis. All the different analysis types are available when a basal plane is included: deterministic, probabilistic, and combination. Sensitivity and persistence analyses can also be carried out. Wedge with basal joint

4 Option to include Basal Joint in Project Settings Basal Joint deterministic analysis input Basal joint analysis Sample socket wedge

5 Design Factor of Safety (Probabilistic and Combination Analyses) In Probabilistic and Combination Analyses, the Design Factor of Safety option is used for determining both the probability of failure and the number of failed wedges in graphs. Design Factor of Safety option in Project Settings Histogram of wedge Safety Factor with Design Factor of Safety = 1.0 (PF=8.84%) Histogram of wedge Safety Factor with Design Factor of Safety = 1.3 (PF=41.59%)

6 Design Standards Based on customer requests and the increased use of design standards in industry, a number of Eurocode design standards have been incorporated into Swedge 6.0. The following design standards have been incorporated: Eurocode 7 Design Approach 1, Combination 1 Eurocode 7 Design Approach 1, Combination 2 Eurocode 7 Design Approach 2 Eurocode 7 Design Approach 3 BS 8006: 1995 Section 7 Reinforced Slopes Users have the ability to view partial design factors, import another design standard, export a design standard, and add user-defined standards. A new tutorial goes through an example of EC Design Approach 1 (Combination 2) and EC Design Approach 2. Partial factors for Eurocode 7 Design Approach 1, Combination 1 Design Standard options in Project Settings Be sure to check out the Design Standards tutorial!

7 Failure Mode Filter The new Failure Mode Filter in Swedge 6.0 allows users to exclude specific types of failure modes from their analysis results, or consider more unconventional failure methods such as sliding upslope. Excluded modes will be considered as invalid wedges, allowing you to focus on any particular failure mode of interest. More Water Pressure Options In Swedge 6.0, there are more ways for users to define water pressure on the joint planes. Failure Mode Filter in Swedge 6.0 Water Pressure input for Deterministic Analysis The following Water Pressure options are available: Filled Fissures % Filled Fissures Custom Pressure Peak Pressure Beneath Crest Peak Pressure Toe Peak Pressure Mid Height The main difference between each of the water pressure distribution models is the location of the peak pressure. The Water Pressure Tutorial provides more detail on the different distributions and when they should be used.

8 Water pressure distribution: Peak Pressure Beneath Crest Water pressure distribution: Peak Pressure Beneath Toe Water pressure distribution: Peak Pressure Midheight

9 Bench Design Slope instabilities in open pit mines present a significant design challenge in geotechnical engineering. Small scale failures can have a direct influence on the overall slope angle and therefore must be considered. Swedge 6.0 includes a Bench Design function that allows users to assess the stability of bench-scale wedges for a range of bench face angles. The following statistics can be plotted for a bench design: The Bench Design Tutorial discusses the new bench design function in detail, and demonstrates its use through an open pit mine example. Bench design dialog Total Probability of Failure Cell Probability of Occurrence Cell Cumulative Probability of Occurrence Cell Probability of Sliding Cell Probability of Failure Bench Loss versus Bench Angle Cumulative Frequency of Failed Wedges Definition of bench design parameters for open pit

10 Bench design in Swedge Conclusion Swedge 6.0 is a major upgrade with a number of important new features. The new basal plane and bench design options alone are significant additions to the program, which both current and new users of Swedge will find useful. Make sure you sign up for the beta program so you can test out the new features yourself! For information on upgrade pricing or demo versions, contact Rocscience at: software@rocscience.com

11 What s New in Swedge Version 6.0: Wedges can now include a basal failure plane (pentahedral wedges). As a result, wedges can now be comprised of 3 joint planes. Bench analysis for determining stability and optimal bench widths (open pit mining). New water pressure distributions. Design standards such as Eurocode and BS8006 are now supported. Multiple units (MPa, KPa, ksf, psf, tonnes/m 2, tons/ft 2 ) 64-bit support. Large combination and probabilistic analyses can now be performed. Import of Dips version 6 files. New and improved graphs. More customizable. New toolbars with large icons Can now filter wedges by sliding mode (sliding on joint 1, sliding on joint 2, etc.) in both probabilistic and combination analyses. Can now define a design factor of safety for probabilistic analyses. Probability is now P(FS<design FS). Added upper hemisphere projection in stereonet view Sensitivity for a single strength criterion on all joints has been added. Failure mode is now a statistical output to Excel files. Improved picking of wedges in scatter plot. Can contour water pressure on the joint planes and show the wetted area. For more information, click here.