EVALUATION OF LAND SUBSIDENCE POTENTIAL BASED ON NATURAL CONSOLIDATION AND WATER TABLE DOWNWARD IN SANITARY LANDFILL TALANGGULO AREA, JAMBI

• Main Author: Zelandi, Muhammad
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/66146
• Institution: Institut Teknologi Bandung

The construction site of municipal solid waste (TPA) with sanitary landfill technology in Talanggulo, Jambi, showing potentially high for land subsidence, based on previous survey. To understand the condition for land subsidence in Talanggulo area, based on the value, geological condition, and settlement factor, it required the analysis and investigation from the pattern and characteristic of sedimentary layer, both its physical and mechanical properties. By getting that information, it can be analyzed and evaluate the influence of geological properties to the land subsidence. The research investigates land subsidence based on two consolidation factors, the settlement based on natural consolidation and the settlement based on decreasing of water table. The method that uses are analytical method (one-dimension consolidation) and finite element method with 3 scenarios: natural consolidation, water table downward and increasing of burden by waste disposal from 3 geotechnical drill in research area (BH-01, BH-02, and BH-03. Result of the geological investigation shows Talanggulo area consist of 6 sedimentary layers, those are silty clay (thickness 3,4 m), silty shale (thickness 3,1 m), sandy silt (thickness 2,7 m), silty sand (thickness 4,3 m), clayey silt (thickness 2,4 m), and clay layer (thickness 4 m). based on compressional index (Cc) and consolidation coefficient (Cv) in research area, it observes the clay and silty clay layer have thick layers, in result of the dissipation process for those layers happens slowly, thus potentially still consolidated and takes much longer. Both land subsidence factors (natural consolidation and decreased water table) are in charge for the settlement, with the geological factors influ subsidence at Talanggulo landfill. Therefore, the research area advised to attain safe percentage of consolidation for sanitary landfill construct, later it need to install geomembrane layer so the water table does not fluctuate by water infiltration from the surface that can affect sedimentary layer.