RocTopple is here!Join the Beta Testing Program

Soon to join our family of software is RocTopple, our new rock toppling analysis program! With

the beta release pending in December, RocTopple will complete our suite of rock slope stability

analysis software, offering users fast and comprehensive solutions to a variety of slope stability

problems. In this first version, we are excited to offer the following features:

Calculation of factor of safety based on a modified Goodman and Bray method

Mohr Coulomb and Barton Bandis joint shear strength models

Application of external loads, bolts, seismic loads and water pressure

Probabilistic analysis

Sensitivity analysis

Interactive 3-D view

And attractive printing and reporting options

Figure 1 – Software 2D and 3D View of the classic Goodman and Bray toppling example.

The analysis of block toppling has its roots in the popular Goodman and Bray method, first

published in Rock Slope Engineering in 1976. In the original publication, a toppling slope subject

to only its weight is deemed unsafe if a positive force is required to stabilize the slope’s toe

block. In RocTopple, the method has been extended to include external forces, and a factor of

safety is then calculated by adjusting the joint shear strength until the toe block is in

equilibrium. The joint shear strength reduction applies to both the Mohr Coulomb and Barton

Bandis models.

In reality, slopes are subject to both natural and man-made disturbances; thus, practicality

demands that these external disturbances be internalized into the analysis. RocTopple not only

offers many different applications of external loads but is also designed to allow users to

interactively apply them.

With a few clicks and moves of the mouse, bolts and line loads can be added onto or edited

anywhere on the slope.

Figure 2 – Once bolt specifications have been assigned, the bolt can be moved along the slope

surface to designate its location. Same idea applies to line loads. Simply click bolt/line load to

edit or move it.

Figure 3 – Users can add as many bolts or line loads as they please.

There are 2 different options in specifying joint pore pressure. The pressure can either be

designated as a percentage fill in the joints, or the user can interactively draw a phreatic surface.

Figure 4 – User drawn phreatic surface.

Finally, distributed and seismic loads can be added to the slope. Distributed loads can be added

to either or both the slope and upper face. Seismic loads are represented by seismic

coefficients, which add to the blocks a force equivalent to a fraction of the block weight.

Figure 5 – Slope with distributed and seismic load (circled).

For greater insight into any problem, RocTopple offers users the option to enter any geometric,

strength and external loads as random variables and calculates a probability of failure. Results

can then be viewed in a variety of graphs.

The following graphs illustrate results generated from a probabilistic analysis using the bedding

width as the random variable.

Figure 6 –Scatter plot with regression line (top left), where the Y-axis is the factor of safety and

the X-axis is the bedding width; data highlighted in red indicate analyses which result in factor

of safety less than 0.99.

Figure 7 – Histogram of bedding width samples; sampled distribution is a normal distribution;

data highlighted in red indicate factor of safety less than 0.99 for the given bedding width.

Figure 8 – Cumulative Plot of sampled factors of safety.

Users can also take the analysis a step further and examine the effects that any individual

variable may have on the outcome.

Figure 9 – A sensitivity analysis can be done on any geometric, strength, or external load

variable.

Figure 10 – Sensitivity plot of slope height and slope angle: factor of safety is more sensitive to

the slope angle.

The interactive 3-D view is a fun way to visualize the slope at the point of failure. By moving the

mouse, the user can see the critical mode of failure of each block.

Figure 11 – 3-D visualization of slope failing (classic Goodman Bray Example).

Your project information is summarized in the RocTopple Information viewer. Available in the

HTML format and for simple copying and pasting, the information viewer is a handy tool for any

report generation.

Figure 12 – Information Viewer.

Likewise, each view in the software has been professionally formatted for printing.

Figure 13 – Print preview of slope view with customizable header and footer.

We are proud to announce the arrival of this new software, but as always, the work does not

stop here. To make RocTopple more practical for us all, we would like to hear from you, what

you would like to see in the program. Feel free to contact us for information about the

RocTopple beta release program or to learn more about this new program.

software@rocscience.com