CONSOLIDATION ANALYSIS WITH COMBINATION OF VACUUM PRELOADING AND SURCHARGE PRELOADING WITH FINITE ELEMEN PROGRAM

• Main Author: Putrawijaya, Angling
• Format: Theses
• Language: Indonesia
• Subjects: Teknik sipil
• Online Access: https://digilib.itb.ac.id/gdl/view/45817
• Institution: Institut Teknologi Bandung

Soft clay is one type of soil that has low bearing capacity. Soil Improvement need to be done before construction. One method can be used is preloading system. Preloading system can make effective stress of soil increase. This increased related with dissipation of pore water pressure whose called consolidation process. Effective stress can be increased by increasing the total stress and reducing the pore water pressure. Both methods are implemented in combination of vacuum preloading and surcharge preloading. Vacuum will reduce the pore water pressure and surcharge preloading will increase the total stress. Analysis with finite element method can represent the actual result. Abaqus is a computer program which finite element based is good enough to be analyzing the consolidation case. The study includes comparison pore water pressure analysis result with field monitoring, gain strength, degree of consolidation check, and comparison settlement. The next step is comparing analysis result with field monitoring. The analysis result showed pore water pressure was reduced in elevation -5 m, -10 m, - 15m and -20 m are 81.86 kPa, 81.7 kPa, 80.8 kPa, 80.9 kPa. While field monitoring in the same elevation are 48.1 kPa, 62.1 kPa, 63.8 kPa and 74.1 kPa. additional analysis is done by comparing the increasing effective stress with surcharge preloading and without surcharge preloading. The analysis result showed the surcharge preloading is 45.74 kPa. There are increasing effective stress in elevation -5m, -10m, -15m, and - 20m are 14.7 kPa, 11.4 kPa 13.42 kPa and 8.94 kPa. In degree of consolidation check, according to the water pressure in elevation -15 m to -20 m showed the same result between analysis and field monitoring. The degree of consolidation in this elevation is 77% from analysis result and 78.5 % from field monitoring. Comparison of settlement showed the differences result between analysis and field monitoring in elevation -4m, - 8m, -12m, -16m, -20m, and -24 m are 164.4 mm (11.3%), 198.13 mm (14.54%), 101,24 mm (9.35%), 264,54 mm (33.03%), 81.8 mm (13.17%), 82.177 mm (25.28 %) and 22.98 mm (16.2%).