Detailed Engineering Design for Slope Mitigation at the Inlet and Outlet Areas – Sultan Alimuddin–Kakap Tunnel Project, Samarinda

The Detailed Engineering Design for Slope Mitigation at the Inlet and Outlet Areas of the Sultan Alimuddin–Kakap Tunnel Project in Samarinda was conducted to ensure slope stability around the tunnel portals, where steep terrain and geotechnical conditions posed landslide risks. The scope of work included geotechnical investigation, slope stability and ground deformation analysis based on existing landslide conditions, evaluation of drainage systems and groundwater effects, and development of the Detailed Engineering Design for slope reinforcement and protection systems at the tunnel inlet and outlet areas. Key challenges included steep slopes with existing landslides, the influence of rainfall and groundwater on slope stability, and the risk of further landslides affecting the tunnel portals and surrounding infrastructure. The technical approach involved evaluating geotechnical stability and slope drainage conditions, optimizing reinforcement and slope protection designs, and developing ground mitigation recommendations to improve the factor of safety and maintain long-term tunnel infrastructure stability.