ROTOMAP
is a three-dimensional model that is used for rockfall analysis
and the design of rockfall protective systems.
This module belongs to the Isomap family: please check the ISOMAP
page for a complete description of the main module features.
ROTOMAP
uses a statistical approach; it simulates a large number of rockfalls
and, through the analysis of the distribution of the average and
maximum kinetic energies, identifies the optimal areas for the installation
of the protective systems.
The
program requires a detailed topographic map and a geomorphologic
data collection to identify the areas where a rockfall can initiate,
and to distinguish the different surface types, such as clean faces
of hard unweathered rock or surfaces covered in talus, scree or
gravel material.
A digital
terrain model can be obtained from an arbitrary distribution of
points (X,Y,Z), that the program can convert into a regular grid,
or by directly assigning the elevation values to the nodal points
of the square mesh that is used in the model.
It
is also possible to import the elevation values from an external
digital terrain model.
A new,
fast model calibration method is now available, thus avoiding carrying
out expensive tests with high-speed cameras.
ROTOMAP
draws the contour lines of the minimum travel times of the blocks;
with a simple chronometer and a standard video camera it is possible
to compare the real and simulated times, in correspondence to pre-determined
check-points.
This
allows a detailed and reliable calibration of the model.
If
in-field tests are not possible, a preliminary back-analysis stage
can be used to determine the restitution and friction coefficients.
These
coefficients can be obtained through a comparison of the points
where the rock blocks stop in the simulation with the rockfall history
stop points.
The
kinetic energy distribution is thus calculated and this permits
both the optimal positioning and the accurate design of barrier
fences or catch benches.
The
maximum bouncing height over the slope can also be drawn. This allows
the selection of the correct size of the barrier fences.
In
this way, the effectiveness of the whole rockfall protective system
can be verified.
The
program can generate printouts of the topographic map, rockfall
trajectories, kinetic energies, distribution of stop points and
the vertical sections of each simulated fall.
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