DEFORMATION AND FAILURE OF CONCRETE LINING IN VERTICAL SHAFT AT INTERSECTIONS WITH HORIZONTAL TUNNELS

The article describes the long-term in-situ observations and inspection of concrete lining in air inlet shaft No. 3 in Uralkali's mine, which reveal the main causes of the lining failure at intersections with horizontal tunnels and in the areas of instable rocks. Numerical modeling of rock creeping and damage areas in lining at intersections with tunnels is performed in the axially symmetric and three-dimensional formulations. The calculations agree with the observation data, which proves efficiency of mathematical modeling in estimation of deformation and failure of concrete lining during shaft design and operation. Prediction of damage evolution in concrete lining in shaft No. 3 is carried out for the next 10 years.