Hi,

YADE [1] is a 3D open-source discrete element code which can be used for rockfall and debris flow analysis. It is a general purpose program so don't expect functions/GUI specific to this topic. It is definitely more advanced than everything else you mentioned. Nevertheless, myself and others are using it for this purpose [2].

HTH

K

[1] https://yade-dem.org/doc/

[2] https://www.yade-dem.org/doc/publications.html

Hi,

You can use CONFALL 1.0,  a program for the quick preliminary estimation of the rock-fall potential of propagation zones.

 http://geotechpedia.com/Software/Show/507/Conefall

For roc fall analyses I use Rocfall software a product from company Rocscience. It is not free but also not so expensive. You can see possibilities on a web page rocscience.com.

HY-STONE , ..

and,

STONE (Guzzetti et al. 2002), a GIS based rockfall simulation software which computes 2D and 3D rockfall trajectories starting from a DTM and maps of the dynamic rolling friction coefficient and of the normal and tangential energy restitution coefficients

http://www.feat.nl/Hy_Stone/hy_stone.html

RocPro 3D software is for the simulation of rockfalls in 3-D. 

You can take a look at it and also try the demo version.

Regards. 

http://www.rocpro3d.com/rocpro3d_en.php

LAHARZ or VOLCFLOW to modelling debris flow

HY-STONE

You could use RAMMS, it is not free, but is not so expensive.

SynxFlow for modelling debris flows (and flood).

https://synxflow.readthedocs.io/en/latest/