Relationship between Modified Mercalli Intensity and peak ground acceleration in Myanmar

Abstract

In this study, the previously reported isoseismal maps are compiled and used to carefully inves-tigate the macroseismic intensity in terms of the Modified Mercalli Intensity (MMI) scale, based on the engineering ground-motion parameter, as the peak ground acceleration (PGA), inferred from the ground-motion attenuation character-istic of Myanmar. The preliminary relationship be-tween the MMI and PGA is reported to be a function of log 10 (PGA) = 0.2526MMI – 3.1006. The strongly correlated MMI-PGA relationship ob-tained in this study, if confirmed, will be par-ticularly useful in real-time applications for dam-age prediction or engineering parameter deter-mination when an earthquake occurs in or near-by to Myanmar. Compared with the previously proposed MMI-PGA relationships for other re-gions, the standards/provisions of building con-struction in Myanmar is not high enough to with-stand the hazards from earthquakes, particularly at higher levels of ground motion. Therefore, the seismic building code of Myanmar should be modified in order to reduce future hazards aris-ing from earthquakes.