Content area
Karst tunnels accumulate localized high water pressure during heavy rainfall, which can potentially induce cracks and damage to tunnel structures. By fully analyzing the stress characteristics of the lining structure and the critical water pressure, this study aims to evaluate the safety status of karst tunnels under heavy rainfall conditions, and proposes detailed tunnel optimization solutions. The results indicate that the outward deformation of the structure is restricted when the water pressure within the cavity is low, thus enhancing structural stability. However, the internal forces of the structure gradually increase as water pressure increases. Additionally, the mechanical properties of the surrounding rock significantly influence the internal forces. The bending moment in the lining structure is highest in the grade III surrounding rock under the same water pressure. However, the critical water pressure of the lining structure differs by surrounding rock grade due to varying constraints, following the order IV > V > III. Moreover, karst cavities located at the arch spandrel exert the greatest detrimental effect on the structure. Furthermore, the critical water pressure and concrete failure modes of the lining structure under different conditions are determined. Lastly, the optimization of the construction and design of the actual tunnel is proposed to enhance the structural integrity of the tunnel lining. These findings provide valuable insights for structural safety assessments under various karst cavity conditions.
Details
Water pressure;
Karst;
Structural safety;
Tunnels;
Rainfall;
Drainage;
Safety;
Mechanical properties;
Rocks;
Tunnel linings;
Tunnel construction;
Case studies;
Design optimization;
Simulation;
Construction;
Bending moments;
Structural integrity;
Failure modes;
Optimization;
Water damage;
Internal forces;
Holes;
Structural stability
; Tang, Xu 2 ; Ma, Xiaoxin 2 ; Wang, Xiaonan 2
1 School of Mechanics and Civil Engineering, China University of Mining and Technology, Xuzhou 221116, China; [email protected] (W.Q.); [email protected] (X.T.); [email protected] (X.M.), State Key Laboratory of Intelligent Geotechnics and Tunnelling, Southwest Jiaotong University, Chengdu 610031, China
2 School of Mechanics and Civil Engineering, China University of Mining and Technology, Xuzhou 221116, China; [email protected] (W.Q.); [email protected] (X.T.); [email protected] (X.M.)