Geo-hydro-mechanics for quantitative landslide hazard assessment (QHA)

Landslide risk represents a strong limitation to the social and economic development of civil society in chain areas. This is particularly the case in highly urbanized regions. The need for mitigation of landslide risk prompts landslide hazard mapping. The aim of the research work presented in the paper is the use of geo-hydromechanics for the assessment of landslide hazard from the site to the small scale. The geo-hydro-mechanical analysis of landslide hazard is first presented to diagnose single slope. To this aim, the procedure for the deterministic analyses of the internal/external slope factors and of the possible landslide processes bringing about instability is presented. The contribution offers an overview of the key steps of the deterministic procedure with the phenomenological interpretation of a landslide mechanism as first, and the numerical validation thereafter. A representative case study of application of the methodology is discussed. The case study is representative for chain slopes in the Italian Apennines and exemplifies the geo-hydro-mechanical diagnosis of landslide hazard in complex geological contexts. As second, a methodology for intermediate to regional scale landslide hazard assessment, based on geo-mechanical interpretations, is also recalled. The methodology is the Multiscalar Method for Landslide Mitigation, MMLM (Cotecchia et al. 2016b; Cafaro et al. 2016). It uses the hydro-mechanical diagnoses of landsliding at the slope scale as reference starting point. In this contribution, a brief example of the validation of the MMLM to the geologically complex Daunia-Lucanian Apennines (Italy) is also shown