
Seismic Zone "Kresna" in South-Western Bulgaria and the Infrastructure Projects in the Area
Authors
Kiril Anguelov, Dobrin Denev, Kiril Anguelov
DOI
Abstract
On April 4, 1904, an earthquake with a magnitude of 7.9 on the Richter scale occurred on the territory of the Kresna Gorge (South-western Bulgaria). The earthquake is a consequence of activity along a fault (Krupnishki Fault), which crosses almost perpendicularly the meridional Struma fault zone along which the Struma River flows. As a result of the earthquake, several deep cracks were formed, where the waters of the Struma River were completely drained in a few hours.
At the moment for the Bulgarian designer and builders stands the important and significant goal for the construction of the last highway section of the Struma Highway.
The highway is built almost entirely in between Sofia and the border with Greece ("Kulata – Promachonas” customs). Considering the complex seismic situation the question for the best and safest construction remains the part of the highway near the Kresna Gorge.
There are several options for the construction of this section - with a long tunnel, with short tunnels and bridges or with the construction of one-way high-speed road sections in both directions. In the following report we will make a comparative assessment of the proposed options.