ANALISIS KESTABILAN LERENG MASSA BATUAN DAN LONGSORAN PADA RUAS JALAN TAWAELI-TOBOLI KM 39-42, KABUPATEN DONGGALA, PROVINSI SULAWESI TENGAH

• Main Author: KARISMA LINDIA , EVA
• Format: Final Project
• Language: Indonesia
• Subjects: Geologi, hidrologi & meteorologi
• Online Access: https://digilib.itb.ac.id/gdl/view/27008
• Institution: Institut Teknologi Bandung

<p align = "justify">Studied area is located at KM 39-42Tawaeli-Toboli Road Segment, Donggala Regency, Central Sulawesi Province with coordinates of 0o 43’ 26,98’’ S, 119o 58’ 37,23’’ E to 0o 43’ 39,24’’ S, 119o 59’ 12,69’’ E. Morphology of studied area was formed by hills with tight contours and developed steep slopes. Resistant lithology was formed by schist belonging to Metamorphic Rock Complex of Pre-Tertiary age. Studied area has steep rock slopes as excavation results for road widening project and spotted several failures. The location of observation of rock slope is divided into five spots that are SC-132, SC-138, SC-142, SC-155 and SC-159. Physical property test is obtained weight values of 25.27 kN/m3 to 28.19 kN/m3, while index property test is obtained Schmidt hammer values of 32.25-44.8 showing the strong to very strong rocks. The geological hazard identification of potential failures were observed visually as quantitative method. Quantitative method was applied on the rock mass slopes based on discontinuity character in order to slope stability analysis. In the five observation spots, the Rock Mass Rating (RMR) classification presents fair rock category at SC-132 and SC-138, while good rock category at SC-142, SC-155 and SC-159. The kinematic analysis of failure mode shows toppling failure percentage of 0.69% to 63.25%. Slope Mass Rating (SMR) classification presents partially stable to unstable slope at SC-132, SC-138, SC-142 and SC-155 with IIIb to IVa class, while stable slope at SC-159 with IIb class. Overall, rock mass slopes at studied area have a relatively stable condition as well as not prioritized for re-excavation. Some support systems are needed to keep the rock slope permanently stable in some spotted areas. Suggestion supports are based on SMR classes such as toe ditch, nets, shotcrete, systematic rockbolt or anchor, toe wall and drainage.<p align = "justify">