2-D WAVE PROPAGATION ANALYSIS TO DETERMINE THE CORRECTION FACTOR OF THE BASIN EFFECT RESULTING FROM 1-D WAVE PROPAGATION ANALYSIS

• Main Author: Mandhany, Anggariano
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/65916
• Institution: Institut Teknologi Bandung

The Basin effect has been known to affect the response of earthquakes on the ground surface, especially in areas close to the edge of the basin. One of the studies that discusses the geometric effect is discussed by Bard and Gariel (1986). The result of this study, from on 1-D and 2-D analysis, there is a quiet big difference in amplification values at the edge of the basin from 1-D and 2-D analysis. In the practical application, seismic studies were done using 1-D wave propagation analysis to develop such city microzonation maps. Based on practical considerations, it is necessary to have research to predict the correction factor of the 1-D analysis by considering the basin effect of the 2-D analysis. The modeling was performed using DMOD2000 for 1-D analysis and FLAC for 2- D analysis. Moreover, in the modelling processes, it is used 4 (four) variations, including, variation of the Peak Ground Acceleration (PGA) value from the input motion, variation of basin angle (?), variations in the ratio of basin depth and basin width (D/W), and variations of basin width. The results of the 1-D and 2-D modelling are the spectral acceleration values which are compared to a value of a correction factor. From the analysis, it is found that the correction factor is affected by the value of PGA input motion, the basin geometry both from the basin angle, width and the basin depth.