2D SITE-SPECIFIC RESPONSE ANALYSIS TO IDENTIFY THE EFFECT OF SOIL GEOMETRY AND SITE-CLASS ON SAND RECLAMATION EMBANKMENT

• Main Author: Nyoman Sutrisna Angga, I
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/68699
• Institution: Institut Teknologi Bandung

Most of reclamation projects are constructed using sandy soil. Reclamation are carried out to acquire new land to build infrastructure on it. Indonesia, which is an area where several tectonic plates colide, causes Indonesia's seismic activity to be quite frequent. To produce a reclamation embankment that meets the standards, it is necessary to take into account the effects of the earthquake, the local soil (site class), the geometry and properties of the embankment. This study aims to carry out site specific response analysis in 2D with Jakarta soil investigation data, in order determine the amount of amplification on the surface due to earthquakes. The study will includes variations in parameters such as embankment height, soil site class, relative density of sand, and earthquake input motion. Model verification is carried out by comparing 1D wave propagation in FLAC software with DEEPSOIL software in accordance with the research recommendations of Hutabarat (2016). The results of the study divide the soil layer just below the embankment into 3 zones. The zones are the zones without embankment, the transition zone, and the zone with embankment. In the zone without embankment, it is found that the magnitude of the acceleration response that occurs is greater when the approaches the embankment slope. Transition zone is a zone that is near the slope but there is an embankment on it. The magnitude of the acceleration response obtained by the average PGA is 3.4x greater than the no-embankment zone. The width of the transition zone ranges from 1.5x - 2x the height of the embankment above, at a height of 5m embankment the width of the transition zone is 7.8m - 9m from slope toe while at a height of 10m the width of the transition zone is 18.3m - 20m from the slope toe. In the zone with the embankment, the smallest acceleration response is obtained than in the other zones. The transition zone that already has an embankment above it is affected by the geometric effect of the adjacent slope so that even though there is an additional effective stress from the embankment above it, this zone still produces the largest acceleration response value. This study also discuss of deformation that occurs along the embankment. The results obtained show that in the transition zone the magnitude of deformation is 7-8x greater than the zone without embankment and 10-12x greater than the zone with embankment.