Optimal Slope Angles and Berm Configurations for Rockfall Hazard Reduction Using Discrete Element Modelling and Statistical Analysis

Muhammad Aminuddin Khalid; Mohd Firdaus Md Dan; Faizal Pakir; Khaidir Abu Talib; Aizat  Mohd Taib; Nordiana  Mohd Mustaza; Aniza Ibrahim; Dayang Zulaika  Abang Hasbollah; Aziman  Madun; Eka  Kusmawati Suparmanto

Authors

Muhammad Aminuddin Khalid Universiti Tun Hussein Onn Malaysia
Mohd Firdaus Md Dan Sustainable Geostructure and Underground Exploration, Faculty of Civil Engineering and Built Environment, Universiti Tun Hussein Onn Malaysia, 86400 Batu Pahat, Johor, MALAYSIA
Faizal Pakir Universiti Tun Hussein Onn Malaysia
Khaidir Abu Talib Universiti Tun Hussein Onn Malaysia
Aizat Mohd Taib Department of Civil Engineering, Faculty of Civil Engineering and Built Environment, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor, MALAYSIA
Nordiana Mohd Mustaza School of Physics, Universiti Sains Malaysia, 11800 USM, Penang, MALAYSIA
Aniza Ibrahim Department of Civil Engineering, Faculty of Engineering, Universiti Pertahanan Nasional Malaysia, Kem Sg Besi, 57000, Kuala Lumpur, MALAYSIA
Dayang Zulaika Abang Hasbollah Centre of Tropical Engineering, Faculty of Civil Engineering, Universiti Teknologi Malaysia, 81310 UTM Johor Bahru, MALAYSIA
Aziman Madun Sustainable Geostructure and Underground Exploration, Faculty of Civil Engineering and Built Environment, Universiti Tun Hussein Onn Malaysia, 86400 Batu Pahat, Johor, MALAYSIA
Eka Kusmawati Suparmanto Centre of Excellence for Engineering and Technology (CREaTE), Public Work Department Malaysia, 78000 Melaka, MALAYSIA

Keywords:

Rockfall, Slope angles, Discrete element method, Statistical analysis, Destruction distance, Kinetic energy

Abstract

Construction on hilly terrains in Malaysia increases the risk of rockslides, which pose a threat to lives and infrastructure. Despite extensive studies on rockfall dynamics, the influence of slope angles on the destructive reach and kinetic energy (KE) of falling boulders remains unclear. This study aims to identify the slope angles that influence impact distance and KE across various slope geometries, providing valuable insights for protective design measures. Slope angles (ranging from 15º to 90º) and ratios, as defined by the Jabatan Kerja Raya Malaysia (JKR) standards, were analysed using the Discrete Element Method (DEM) and statistical analysis. The study took into account slope angles, slope ratios, and boulder properties. The results indicated that destruction distance peaks at a slope angle of 60°, with the most hazardous slopes occurring between 45° and 60°. KE increased significantly between 35° and 60°, with the near-vertical slopes (up to 90°) generate the highest energy due to greater gravitational forces. Slope ratios of 1:1 and 2:1 produce longer destruction distances and higher KE values, with the 2:1 ratio (63.43°) being particularly critical. Berms were found to effectively reduce both the destruction distance and KE, particularly at slope ratios of 3:1 and 4:1. These findings provide quantitative design guidance on critical slope angles and berm configurations for reducing rockfall hazards based on DEM modelling aligned with JKR slope design standards.