The integration of terrestrial laser scanning and numerical modelling in landslide investigations

Terrestrial laser scanning (TLS) can be used to either complement or replace traditional methods of characterizing both the geometry and structural geology of unstable slopes. TLS data collected from a failed bedrock slope threatening the main east–west highway in the Bhutan Himalaya are presented and interrogated for structural information. The structural data, along with TLS-derived slope geometry and cross-sectional profiles, are suitable for use within commercially available slope stability packages to derive solutions for the causes of instability, likely geometry of failure, and future activity under varied scenarios. The methods also allow the possibility of future model verification and calibration though TLS monitoring. The results of TLS-based numerical modelling utilizing a commercially available code are presented and the implications for slope surveying, numerical modelling, monitoring and management are discussed.