Kinematic assessment of a rockfall disaster: a case study from Batseri Village, Sangla Valley, Himachal Pradesh, India
摘要
In Batseri Village of Sangla Valley, a rockfall incident occurred during the monsoon season on July 21, 2021. To assess the kinematics of this rockfall event, a comprehensive study was conducted, involving detailed field investigations, video frame analysis, and numerical modelling. During the rockfall, a resident captured 10 m3 elliptical rockfall boulder motion using a mobile phone camera providing crucial data for tracking and analysing its trajectory. The video of the boulder showed rotational motion along its minor axis after impacting an embedded boulder. The field investigation revealed that the rock mass exhibits three prominent sets of tectonic joints. The weathering along these tectonic joints and topography formed denudation joints at the top of the escarpment, which led to the rock mass failure. Through numerical simulations, it was determined that the potential threat section of the Sangla–Chitkul road at Batseri village spanned approximately 400 m. For boulders passing this road section, the maximum velocity reached 46 m/s, whilst the maximum kinetic energy peaked at 5.9 × 104 kJ, and the highest jump height was measured at 9 m. The analysis of kinetic energy and jump height provides essential parameters for designing effective protective measures. Understanding the rockfall characteristics and potential reach is crucial in developing strategies to safeguard vulnerable areas and mitigate the impact of future rockfall events in Batseri village. The combination of field observations, video frame analysis, and numerical modelling enhances our understanding of rockfall behaviour and informs protective design efforts for infrastructure and communities in the Batseri Village.