Assessment of the ground motion levels for the Vrancea (Romania) November 1940 earthquake

Abstract

This short paper focuses on the evaluation of the ground motions levels likely experienced in ten cities seriously damaged during the November 1940 intermediate-depth Vrancea (Romania) earthquake (M W = 7.7). In the first step of the analysis, the ground motion levels are evaluated using a recently developed ground motion model (Vacareanu et al. in J Earthq Eng 19 (3):535-562, 2015) for the Vrancea intermediate-depth seismic source. Next, the stochastic method of simulation (Boore in Pure App Geophys 160: 2003) is employed in the same purpose. In order to include the nonlinear soil effects into the results of the stochastic simulations, a dedicated amplification function is derived from the ground motions recorded during two large magnitude Vrancea earthquakes in 1986 and 1990. The results obtained for the November 1940 Vrancea earthquake show that the largest spectral ordinates are obtained when the nonlinear soil effects are taken into consideration, while the peak ground accelerations are in almost all cases in excess of 0.15 g. In addition, the results for Bucharest are validated through a site-specific response analysis performed using a soil profile from the literature. This site response analysis for the 1940 seismic event reveals long-period spectral amplitudes, similar to the ones observed in Bucharest during the Vrancea 1977 earthquake.

Mapping accessibility for earthquake hazard response in the historic urban centre of Bucharest

“…8), but their capacity should be assessed against the probable number of casualties, which could reach as high as 11 000. The earthquake of 1940 registered 1271 and the 1977 earthquake 11 321 injured persons (Pavel and Vȃcȃreanu, 2015). The location of Colţea Hospital suggests that the majority of injured persons would go there for immediate treatment.…”

“…The Vrancea seismic area is responsible for the highest seismic risk in Romania (Pavel et al, 2014;Ardeleanu et al, 2005). Over the past 76 years, Bucharest has been affected by four earthquakes with a magnitude of between 6.9 and 7.7 on the Richter scale (November 1940, March 1977, August 1986, and May 1990.…”

An Updated Perspective of the Impact of the 1940 Vrancea Earthquake on Design and Construction Practices in Romania

“…Various solutions for ground motion estimations have been proposed in the literature using both seismological parameters as well as macroseismic observations. Since no ground motion was recorded during this event, a discussion regarding an estimation of the ground motion amplitudes during the Vrancea intermediate-depth seismic event of November can be found in the studies by Pavel and Vacareanu [17] and Pavel and Vacareanu [18]. In the latter study, the ground motion amplitudes were derived starting from the macroseismic intensities of the event, while in the former study, the procedure involved both ground motion prediction equations as well as stochastic ground motion simulations.…”