EXPERIENCE IN GEOSTRUCTURAL AND GEODYNAMIC INVESTIGATIONS OF NUCLEAR POWER PLANT ALLOCATION TERRITORIES FOR ASSESSING STABILITY OF ENGINEERING STRUCTURES

Abstract

The results of geological and structural-geodynamic research are presented for the territories of several nuclear power plants (NPP) located on the East European Platform. The influence of geological structure, lithology, and the latest tectonic movements are considered as well as the resultant structures and relief, which generally represent the geological environment, on the stability of the NPP areas. Structural and geodynamic conditions, in particular, recent tensile stresses that cause intense rock fracturing and high gas-fluid permeability, suffusion, karst and landslide, are proved to be the main causes of hazardous processes resulting in settling and tilting of some NPP buildings. Tectonic sloping of the sites towards descending depressions, the sand basement of NPP sites, sloping clay aquicludes, fluctuating water levels in the adjacent water reservoirs, the presence of so-called “hydrogeological windows”, the buried relief and modern structural and geodynamic conditions, i.e., tectonic stresses (tensile stresses in many cases) contribute to building deformations. Along with solving practical problems, a number of theoretical issues are considered. Lineaments are associated with rock fracture zones and faults zones; the fault zones in crystalline foundation influence the formation of recent structures; and new platform structures, i.e. gravity-tectonic massifs and pull-apart depressions, are distinguished.