Mechanism for reactivation in ancient landslide induced by mountainous highway

The research focuses on ancient landslides in south-west China’s mountainous areas, which are often overlooked due to their blending with the natural terrain. A case study from a bridge slope in Yunnan Province is used to investigate the reactivation of these landslides. This study explores the reactivation mechanisms of ancient landslides triggered by construction excavation disturbances combined with rainfall infiltration, a topic rarely examined in mountainous plateau regions. Through extensive monitoring of both surface and deep displacements during highway construction, the study reveals the dynamics of landslide resurgence. It identifies engineering excavations and pre-existing ancient sliding zones as the primary triggers for slope instability, with rainfall infiltration exacerbating the issue and causing a complex, layered sliding pattern. Numerical simulations are employed to recreate the landslide’s resurgence, forecast its future behaviour and guide reinforcement strategies. This research underscores the significance of correctly identifying ancient landslides and implementing appropriate mitigation measures in construction projects, offering valuable insights for hazard management in similar geological settings.