Study on the Creep Characteristics of Sandstone under Coupled Stress-water Pressure

  • Zuosen Luo Collaborative Innovation Center for Geo-Hazards and Eco-Environment in Three Gorges Area, 443002, Yichang, Hubei, China; Key Laboratory of Geological Hazards on Three Gorges Reservoir Area, China Three Gorges University, Ministry of Education, 443002, Yichang, Hubei, China
  • Jianlin Li Collaborative Innovation Center for Geo-Hazards and Eco-Environment in Three Gorges Area, 443002, Yichang, Hubei, China; Key Laboratory of Geological Hazards on Three Gorges Reservoir Area, China Three Gorges University, Ministry of Education, 443002, Yichang, Hubei, China
  • Lehua Wang Collaborative Innovation Center for Geo-Hazards and Eco-Environment in Three Gorges Area, 443002, Yichang, Hubei, China; Key Laboratory of Geological Hazards on Three Gorges Reservoir Area, China Three Gorges University, Ministry of Education, 443002, Yichang, Hubei, China
  • Eleyas Assefa College of Architecture and Civil Engineering, Addis Ababa Science and Technology University, 1000, Addis Ababa, Ethiopia
  • Huafeng Deng Collaborative Innovation Center for Geo-Hazards and Eco-Environment in Three Gorges Area, 443002, Yichang, Hubei, China; Key Laboratory of Geological Hazards on Three Gorges Reservoir Area, China Three Gorges University, Ministry of Education, 443002, Yichang, Hubei, China

Abstract

Long-term interaction between stress and water pressure leads to creep damage of reservoir bank slope. As a result there will be instability of the bank slopes in many water conservancy projects. The rock mass creeping effect of coupled stress-water pressure was studied by using a typical sandstone rock from the Three Gorges reservoir area. The experiment was conducted by using the rock immersion-air-drying cyclic load rheometer device (designed and manufactured by our research team). Based on the experimental results, the following key points were observed: 1) the creep strain and the steady-state creep rate was increasing when the water pressure increased (at the same stress level). Under the same water pressure, the increase in the axial pressure resulted in the increase in the creep strain and steady creep rate of the sandstone specimens. 2) the increase in the axial pressure increased the creep strain and steady-state creep rate of the sandstone specimens while the water pressure increased. The mechanical properties of the sandstone specimens were affected by the water pressure. 3) the water infiltrates through the pore surfaces. As a result, the rate of deformation will increase while the bearing capacity and long-term strength of the rock decrease. This paper provides a solid theoretical foundation for the evaluation and prediction of reservoir geological hazards.

Keywords: rock mechanics, sandstone, creep, water pressure
Published online
2019-10-24
How to Cite
Luo, Z., Li, J., Wang, L., Assefa, E., & Deng, H. Study on the Creep Characteristics of Sandstone under Coupled Stress-water Pressure. Periodica Polytechnica Civil Engineering. https://doi.org/10.3311/PPci.14706
Section
Research Article