Development and knowledge for assessing the stability of rock masses and rock slopes in Bulgaria

This article examines the stages of construction of infrastructure in Bulgaria. Much of the existing railway infrastructure was built in the late 19th and early 20th centuries, when in practice there were no formulated requirements for assessing the stability of rocky slopes and workings carried out in rocky terrains. For this reason, the development of different methods for assessing the construction qualities of rock massifs is being considered. It is stated that the first methods for estimating the rock massifs are based only on the engineering-geological properties of the rocks, but not on their geostructural features. The development of methods for assessing the stability of tunnels and rock excavations, as well as the entry into them of necessary data from studies on the geostructural properties of rock massifs, are considered. Examples are given of the use of different methods in the assessment of the stability of rock slopes and tunnels in Bulgaria. It is emphasized that in the latest publications, the properties of the rock masses and their stability are described on the basis of the latest knowledge in the field of geostructural geology, geotechnics and normative documents.