Mechanism and Rectification Method on Difficult Tomo Landslide, Sumedang, West Java, Indonesia

Tomo landslide is located on the slopes of the Sumedang Cijelang National Road Section KM 68 + 650. At the toe of the slope, there is a national access road and the Cimanuk River. Landslides previously occurred in 2020 on the West side and 2021 on the East side. And the most recent landslides event (November 2021 landslides) resulted in damage to the national road and the existing retaining wall which was reinforced with bored pile foundations with the diameter of 600 mm as an emergency measure to overcome further movement. However, ground movement is still occurring. The landslide rectification is combined with the concept of re-shaping and slab on pile where the national access road is placed on top of rigid pavement which is supported by bored piles. Since the debris material is still moving, it is allowed to move through beneath the slab and between the pile structure towards the toe of the slope, and the piles are designed to resist debris movement.