TRQDM (Return Time of the Quasi Dynamic slope stability Model)


This program is free software. This program is distributed in the hope that it will be useful, but without any warranty; without even the implied warranty of merchantability or fitness for a particular purpose.




TRQDM is a module for the calculation of the return time from the critical rainfall map spatially distributed under the scaling hypotheses to IDF (Intensity Duration Frequency) relationship. In the Figure 1 is showed the interface of the program.




Figure 1. Interface of TRQDM




Input section

Format header file (.hdr): georeferentation and main information (cell size, number of rows and columns) of grid files

Critical rainfall grid file (.flt): critical rainfall grid as the slope stability index of the quasi dynamic model (Borga et al., 2002)


Output section

Return time grid file (.flt): return time grid


Numerical parameters

Time: duration of the critical rainfall expressed hours

a1, CV, n: GEV parameters for the computation of the IDF under the scaling approach


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Borga, M., Dalla Fontana, G., and F. Cazorzi (2002). Analysis of topographic and climatic control on rainfall-triggered shallow landsliding using a quasi-dynamic wetness index, Journal of Hydrology, 268(1-4), 56-71.

Tarolli, P., Borga, M., Dalla Fontana, G. (2008). Analyzing the influence of upslope bedrock outcrops on shallow landsliding, Geomorphology, 93, 186-200,  doi:10.1016/j.geomorph.2007.02.017.

Tarolli, P., Borga, M., Chang, K.T., Chiang, S.H. (2011). Modeling shallow landsliding susceptibility by incorporating heavy rainfall statistical properties, Geomorphology, 133, 199-211, doi:10.1016/j.geomorph.2011.02.033