3D PREFABRICATED VERTICAL DRAIN MODELLING AND CONSOLIDATION ANALYSES TAXIWAY I MEDAN BARU – KUALA NAMU AIRPORT (CASE STUDY)

• Main Author: NUMAN (NIM : 25006310); Pembimbing : Prof. Dr. Ir. A. Aziz Jayaputra, MSCE, AHMAD
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/14740
• Institution: Institut Teknologi Bandung

In order the water flow into vertical drain under an embankment loading is axisymmetric problem, three dimensional behaviour of an embankment on soft soils incorporating PVD is analysed using Plaxis 3D Foundation V 2.2. The method was applied 3D numerical analyses of an embankment on soft soils incorporating PVDs, in combination with a constitutive model called soft soil and Mohr Coulomb in Plaxis 3D. The first set of finite element analyses was conducted with 3D modeling of a single drain and its influence zone underneath the center line of embankment. This first set was conducted to study the behavior of a PVD and its smear zone, a disturbed zone induced during installation of PVDs. Vary of ds/dw and kh/ks ratio was conducted. This first set was also verivified the method by Chai et al. (2001) by comparing the result of a 3D PVD unit cell with a 3D unit cell Chai et al. method, which had a good agreement with each other. The method by Chai et al. (2001) uses an equivalent vertical hydraulic conductivity, kve, to represent the drainage by PVDs. <br /> <br /> <br /> Another set of finite element analyses was a full scale model. A 3D multi drain analyses, with modelling drains and the surrounding smear zone for each and every drains cannot be modelled due to the software limatiation (the size is too slender to be modelled). So that, the method by Chai et al. (2001) was applied to 3D analyses of the full scale embankment on PVD improved soft soil. For verification, the simulation were also compared with the field measurements. Based on settlement results, the method proposed by Chai et al. appears to be useful tool for engineering practice. <br /> <br /> <br /> As consolidation progresses in the soft soil under embankment load, the dissipation of pore water pressure will occur and hence the undrained strength will increase. Using several formula such as Mohr Coulomb, Modified Cam Clay’s Critical Soil Mechanics Concept, Mesri, Jamiolkowski and Skempton, the increases of undrained strength is analysed.