DEVELOPMENT OF SEISMIC MICROZONATION MAP OF MALAY BASIN FOR OFFSHORE FACILITIES

Soft soil in offshore regions may cause vibrations experienced by offshore structures, particularly the current fixed jacket platforms that were built without consideration for seismic in Malaysian waters. In order to develop a map of seismic microzonation, a map of soil amplification factors according to soil type, proposed designed horizontal response spectra and site coefficient values (Ca and Cv) for Malay basin, this study was created. For the ground response analysis of six selected seismic events with five return periods of 100, 200, 500, 1000, and 2500 years, a 1-Dimensional nonlinear analysis of layered soil (NERA) was utilised. Peak surface acceleration (PSa), the soil amplification factor, and the designed horizontal response spectral acceleration for the research area were all determined through analysis. The results demonstrate that the PSa value for soil type E is often greater than that for soil type D, and the PSa exhibits an increasing tendency when compared between a return time of 100 years and 2500 years.