Speaker
Description
A study examined seismic hazard in Thailand's central plain, characterized by a thick quaternary basin. Unconsolidated sediments may amplify seismic ground shaking, potentially increasing structural damage. The research resulted in a fundamental frequency map derived from HVSR analyses at 149 microtremor sites. A Vs30 map was subsequently generated using HVSR inversion methods, alongside a soil classification map based on NEHRP standards. The upper central plain near the Yom and Nan Rivers demonstrated a low fundamental frequency of 0.3-0.5 Hz and low Vs30, categorizing it as soil type Class E. In southern Ayutthaya, Pathum Thani and central Bangkok, an extremely low Vs30 below 100 m/s suggested soil class F or special soft soil. A thorough probabilistic seismic hazard analysis was performed, considering Vs30 conditions. The northern upper central plain and western central basin showed relatively high seismic hazards. Additionally, site effects notably amplified ground motion at the 1.0 second period, exceeding Thailand's earthquake-resistant design standards by over five times, particularly in the central lower plain region.
| [email protected] |
