To quantitatively assess the landslide hazard in
Khelvachauri, Georgia, the statistic method of hazard index was applied. A
spatial database was constructed in Geographic Information System (GIS)
including topographic data, geologic maps, land-use, and active landslide
events (extracted from the landslide inventory). After that, causal factors of
landslides (such as slope, aspect, lithology, geomorphology, land-use and soil
depth) were produced to calculate the corresponding weights, and thereby we
defined a relevant set of spatial criteria for the latter landslide hazard
assessment. On top of that, susceptibility assessment was performed in order to
classify the area to low, moderate and high susceptible regions. Results showed
that NW aspect, mountain geomorphology, private land-use, laterite loam and
clay, slope between 19 to 24 degrees, and soil depth between 10 - 20 cm were
found to have the largest contribution to high landslide susceptibility. The
high success rate (72.35%) was obtained using area under the curve from the
landslide susceptibility map. Meanwhile, effect analysis was carried out to
assess the accuracy of the landslide susceptibility, indicating that the factor
of slope played the most important role in determining the occurring
probability of landslide although it did not deviate as much as other factors.
Finally, the vulnerability analyses were carried out by means of the Spatial
Multi-Criteria Estimation model, which in turn, led to the risk assessment. It
turned out that not so much of the number of buildings (~ 34.13%) was
associated with high-risk zone and that governmental and private land-use
almost accounted for the same risk (39.9% and 40.9%, respectively).