STUDY ON DYNAMIC ANALYSIS ADOPTING EFFECTIVE STRESS APPROACH FOR LIQUEFACTION POTENTIAL EMBANKMENT

• Main Author: Sulaiman, Ahmad
• Format: Theses
• Language: Indonesia
• Subjects: Teknik (Rekayasa, enjinering dan kegiatan berkaitan)
• Online Access: https://digilib.itb.ac.id/gdl/view/45136
• Institution: Institut Teknologi Bandung

Simplification method is a practical and simple method in liquefaction analysis. However, the disadvantage of this method is that it cannot model the excess pore water pressure and deformation due to occurance of liquefaction. The non-linear dynamic analysis with an effective stress approach can show deformation and excess pore water pressure at each loading time. Specifically in this study an analysis was carried out using the effective stress approach for liquefaction potential embankment. The objective of the study is to find out the relationships between the height of the embankment, earthquake loading, relative density of sands, and site classes on horizontal deformation and increases of excess pore water pressure. The independent variables used in this study are input ground motion that consists of megathrust and shallow crustal, embankment heights of 5 m and 10 m, site classes (SD and SE), and relative density of sands with Dr values of 40% to 80%. Liquefaction potential analysis is conducted numerically by using a finite difference method FLAC Dynamic 2D software. Independent wave propagation carried out from the subsurface rock to the ground surface of the model is conducted using NERA software. To compare 1D to 2D wave propagation analysis, the two review points were analyzed in this study, which is close to the slope and far to the slope. The results of the analysis obtained are then linked to empirical calculations of liquefaction using Boulanger (2006) and Luna & Frost (1998). Results of the analysis shows that the density of sand soils with Dr = 80% do not cause liquefaction under 0.1g to 0.5g earthquake load for 5 m and 10 m embankment height. However, the resulted deformations need to be considered in certain schemes of analysis. The increases of excess pore water pressure at a close print to the slope and far to the slope location will increase as the decreasing embankment height. Meanwhile, horizontal deformation at close to the slope will increases as the height of the embankment increases, but horizontal deformation at the far of the slope will decrease with increasing embankment height. For practical needs, deformations on the embankment can be determined empirically make use of the LPI (Liquefaction Potential Index). In addition, recommendation relationship between excess pore water pressure, deformation, height of embankment, relative density of sand, site class, and PGA are presented in this study.