Communication and technological solutions regarding the construction of shelter objects at underground railway stations in fractured and water-logged rocks

Abstract

The purpose of the work is to substantiate the choice of locations of underground shelter objects for the people protection during the warlike situation and methods and facilities for ensuring their stability and isolation, and to develop a combined supporting scheme taking into account mining and geological conditions. It is proposed to arrange the shelter objects in the vicinity of the boarding platforms of the underground railway stations connecting them with the passages, means for walking downstairs and upstairs and a transport network and providing areas for the long-term stay of people, areas for sleeping and eating, shower room, medical, shopping and other necessary blocks. The shelter should be connected to the networks of the underground railway station - electricity supply, water supply and drainage, ventilation and air conditioning. Sleeping areas should be built in the form of individual compartments and arranged in several tiers along the walls of the shelter object. This arrangement of underground objects will make it possible to create a single complex (the shelter object and subway station), reduce the total cost of the shelter construction, speed up the evacuation of people in the event of natural or man-made disasters or air strikes, and ensure a long-term comfortable stay for people. Load on supporting and parameters of roof-bolting systems were calculated for three categories of stability, which correspond to the conditions of the construction of underground railways in the Ukrainian crystalline shield. An algorithm for calculating parameters of the strengthened insulating-reinforcing protection system was built, which takes into account three types of support - rock-bolt structure, insulating-reinforcing rock-polymer layer and tubing. The developed technological solutions for the construction of underground objects assumes pre-bolting of their vaulted part according to a scheme which strengthens the interaction between the rows of bolts, improves the condition of the roof of the object, and ensures protection of the roadway and unsecured part near it during construction of the roadway. The rock-polymer layer protects the tubing against metal corrosion and leaching of concrete under the influence of groundwater, and, due to the high adhesiveness of the polymer resin, also binds the rock-bolt structure, the insulating-reinforcing rock-polymer layer and the tubing into a single reinforced system, which distributes the load around the object's perimeter. The use of modern elastic polymer resins in the protection system will contribute to resisting the alternating loads that spread in the soil during surface explosions, and ensures long-term stability and waterproofing of shelter object. The results of the research can be used in the development of scientific prerequisites for the improvement of methods and means of construction of underground shelter objects in order to ensure the safety of their operation in case of emergency situations. Keywords: underground structures, underground railway station, support, bolts, polymer resins.