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We use ground-motion simulations of the 2013 Bohol, Philippines, earthquake along with a new post-disaster exposure/damage database to constrain building fragility and vulnerability. The large number of damaged buildings (>70,000) and the wide spread of seismic intensities caused by this earthquake make it an ideal candidate for such a study. An extensive survey was conducted leading to a robust description of over 25,000 damaged and undamaged structures. Ground-motion fields were simulated using ground-motion prediction equations and stochastic modeling, and the estimated and observed values were compared. The finite source model used in the simulation was based on the analysis of aftershocks and SAR data. The ground motions were associated with the empirical database to derive fragility and vulnerability models. Results indicate that the pattern of damage is best captured in the stochastic simulation. Constraints were placed on seismic building fragility and vulnerability models, which can promote more effective implementation of construction regulations and practices.

A network of realtime intensity meters is being established in different parts of the Philippines under a Japan-Philippines cooperation. The intensity meters can record and transmit on a near real-time basis the site-specific levels of groundshaking in terms of macroseismic intensity, peak ground acceleration and peak ground velocity. The intensity meters evaluate earthquake effects using the Philippine earthquake intensity scale – PHIVOLCS Earthquake Intensity Scale (PEIS). Deployment of the instruments was planned according to an optimum distribution with respect to active earthquake generators and vulnerable communities. All manned seismic stations of PHIVOLCS were equipped with an intensity meter while the rest was deployed in relevant disaster risk reduction and management centers. In its initial operation which started in 2012, the network captured several significant earthquakes such as theMw7.2 in Bohol in 2013.

Depths of the partially melted zone and the Moho discontinuity are probably at 18 kilometers and 34 kilometers, respectively beneath Tagaytay seismic station, Luzon, Philippines. This conclusion is based on the shear‐wave velocity structure determined in this study, which indicates the presence of a low‐velocity zone and high‐velocity zone at these depths. The shear wave velocity model was derived from the inversion of five receiver functions of teleseismic earthquakes recorded by the broadband seismometer at Tagaytay. However, due to the very limited information to constrain our initial model, other models with comparable waveform fit were also obtained but with deeper low velocity zone and shallower Moho.

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