Experimental study on yielding and relief pressure support technology of fluid-filled lining in a high-ground stress soft rock tunnel

Liu, Jie; Wang, Bin; Yang, Yunan; Yang, Haoyu; Wang, Yansong; Du, Zhuoxing

doi:10.24200/sci.2024.61505.7350

Experimental study on yielding and relief pressure support technology of fluid-filled lining in a high-ground stress soft rock tunnel

Document Type : Article

Authors

- College of Civil Engineering & Architecture, China Three Gorges University, Yichang City, Hubei Province,443002, China - Key Laboratory of Geological Hazards on Three Gorges Reservoir Area, Ministry of Education, China Three Gorges University, Yichang City, Hubei Province, 443002, China

10.24200/sci.2024.61505.7350

Abstract

High-ground stress soft rock tunnels have experienced large deformations. Yielding and pressure relief fluid-filled lining support technology is an effective method for solving large soft rock tunnel deformation due to the deformation characteristics of high-ground stress soft rock tunnels. To give the surrounding rock a certain amount of deformation space, a layer of fluid filling is set up at the reserved deformation of the tunnel. By creating a force test model of the inflatable carcass and water-filled carcass, the straight section of the tunnel support structure is simulated. When supporting large deformation soft rock tunnels, inflatable and water-filled carcasses produce fluid homogenization load shedding and fluid drainage load shedding effects. Inflatable carcasses and water-filled carcasses without leakage reduce load by about 28% and 7%, respectively. The peak load reduction rate under liquid leakage can gradually reach 100 %. Inflatable carcasses can dissipate up to 90% of the work of external forces acting on the supporting structure. The load reduction rate of water-filled carcass is 1.2 times that of inflatable carcass. Fluid-filled materials can remove load from secondary lining support structures after yielding and pressure relief. Design and construction of high-ground stress soft rock tunnels can be influenced by research results.

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