The main natural and anthropogenic factors determining the nature and mechanics of fractures of deep underground tunnel structures lining are considered. On the basis of the conducted research in underground excavations the systematization of the main forms of destruction is carried out. The composition of water extracts prepared from the destroyed concrete and various forms of neoplasms was investigated. Determination of the number and types of microorganisms - micro-mycetes, bacteria and actinomycetes - was carried out. Based on the results of experimental studies, a conclusion is made about the role of biocorrosion in the destruction of tubing and waterproofing jacket. Particular attention is paid to the impact of pressure water of the Lower Kotlin aquifer, which creates favorable conditions for the development of microbiota and its aggressive effect on structural materials.
