Investigations on Creep Behavior and Fractal Derivative Constitutive Model of Sandstone under Different Drying-Wetting Cycles
Investigations on Creep Behavior and Fractal Derivative Constitutive Model of Sandstone under Different Drying-Wetting Cycles
Tao Li(China University of Mining and Technology); Rui Hou(China University of Mining and Technology); Guokun Liu(China University of Mining and Technology); Qian Han(China University of Mining and Technology); Dingyang Li(China University of Mining and Technology)
26권 1호, 69~78쪽
초록
Sandstone has been regarded as an optimal medium for underground gas storage (UGS). To better understand effects of drying-wetting (D-W) cycles on creep behavior of sandstone, comprehensive experimental investigations including uniaxial compression test (UCT) and uniaxial constant-load creep test (UCCT), were conducted on sandstone specimens under different D-W cycles. Experimental results demonstrate that the UCS and E, instantaneous strain, and steady creep rate of sandstone are greatly influenced by D-W treatment. Steady creep rate of sandstone increases with the increase in stress and D-W cycles, while both the UCS and long-term strength (σ∞) of sandstone specimens gradually decrease with the increase in D-W cycles. A novel fractal derivative creep constitutive model of sandstone considering the variations of viscosity coefficient and D-W cycles is established, which could accurately describe the creep characteristics of sandstone after different D-W cycles in the whole creep process. The influence of D-W cycles on the sensitivity of creep parameters is analyzed to discuss the influence of D-W cycles on creep and damage behavior of sandstone.
Abstract
Sandstone has been regarded as an optimal medium for underground gas storage (UGS). To better understand effects of drying-wetting (D-W) cycles on creep behavior of sandstone, comprehensive experimental investigations including uniaxial compression test (UCT) and uniaxial constant-load creep test (UCCT), were conducted on sandstone specimens under different D-W cycles. Experimental results demonstrate that the UCS and E, instantaneous strain, and steady creep rate of sandstone are greatly influenced by D-W treatment. Steady creep rate of sandstone increases with the increase in stress and D-W cycles, while both the UCS and long-term strength (σ∞) of sandstone specimens gradually decrease with the increase in D-W cycles. A novel fractal derivative creep constitutive model of sandstone considering the variations of viscosity coefficient and D-W cycles is established, which could accurately describe the creep characteristics of sandstone after different D-W cycles in the whole creep process. The influence of D-W cycles on the sensitivity of creep parameters is analyzed to discuss the influence of D-W cycles on creep and damage behavior of sandstone.
- 발행기관:
- 대한토목학회
- 분류:
- 토목공학