ABSTRACT
Underground transport structures with two-layer enclosing structures made of monolithic or prefabricated reinforced concrete, erected by different methods, are considered. A characteristic design feature of these structures is the presence of a potentially filtering layer (joint) between the outer and inner linings, through which uncontrolled migration of groundwater occurs in case of even localised water tightness failure of the outer lining due to its mechanical damage, formation of a technological defect or loss of tightness during construction or operation of the underground structure. Lack of possibility to use traditional methods of repair of reinforced concrete structures gives rise to the problem of necessity to develop a technological solution for restoration of external waterproofing protection of waterlogged two-layer lining of underground structures.The solution is obtained by means of the technical solution developed in ‘Mosinzhproekt’ JSC on the basis of the method of interlayer sectional area injection. It provides for the area injection of sealing polymer injection composition at an angle of 90° inside the sealed sections of a closed profile, arranged also by the method of injection into the cavities of the watered interlayer stratification. The sectioning of the interlayer cavity over the entire area of the watered enclosing structure simplifies the quality control of the injection works, minimises the consumption of the injection composition, ensures the elimination of watering and the arrangement of a reliable and repairable external waterproofing protected structure made of the sealing polymer composition of the structure.
