Application of Shotcrete Technology in the Repair and Reconstruction of Underground Structures

The article explores shotcrete technology as one of the leading methods for restoration, reinforcement, and waterproofing of underground structures with various purposes. Special attention is paid to the analysis of this method’s application features during the repair and reconstruction of structures exposed to moisture, aggressive environments, or significant damage.The physical-mechanical properties of shotcrete, including its adhesion to the substrate, crack resistance, and durability under challenging operational conditions, are examined. The study provides a detailed analysis of modern materials used in shotcreting, such as dry and wet mixtures, polymer-modified compositions, reinforcing fibers, and admixtures that enhance wear resistance and coating strength. A comparative evaluation of shotcrete application methods—dry and wet processes—is presented, highlighting their structural differences, efficiency, optimal use cases, advantages, and limitations. Emphasis is placed on surface preparation requirements, the technological sequence of mixture application, safety measures during work, and the impact of human factors on the final coating quality.A dedicated section of the article showcases practical applications of shotcreting in underground infrastructure projects, including tunnels, mines, utility conduits, pedestrian underpasses, and subway stations. Specific case studies from domestic and international practice demonstrate the technology’s effectiveness in real-world conditions. Challenges encountered during shotcrete-based projects and potential solutions are analyzed. In conclusion, the article underscores the promising prospects for further development and refinement of shotcrete technology in modern underground construction and engineering structure rehabilitation.