Uniaxial compression tests have been conducted on Jinan gabbro under six different axial strain rates ranging from 10-3s-1 to 10-8s-1(0.8×10-3s-1, 0.6×10-4s-1, 1×10-5s-1, 0.7×10-6s-1, 1.6×10-7...Uniaxial compression tests have been conducted on Jinan gabbro under six different axial strain rates ranging from 10-3s-1 to 10-8s-1(0.8×10-3s-1, 0.6×10-4s-1, 1×10-5s-1, 0.7×10-6s-1, 1.6×10-7s-1 and 2.7×10-8s-1). The stress-strain（σ1—ε1） curve and stress-volumetric strain（σ1—εv） curve thus obtained indicate that, as the展开更多
It is important to study the crack growth mechanism, because it effectively demonstrates the dynamic process during the fracturing of materials. We used an ultra-small testing machine and chose a piece of plane glass ...It is important to study the crack growth mechanism, because it effectively demonstrates the dynamic process during the fracturing of materials. We used an ultra-small testing machine and chose a piece of plane glass of 48×28×1 mm3 in size as an experimental sample. A small pre-crack 2 a0, less than 5 mm long, was created in the展开更多
Uniaxial compression tests have been conducted on Jinan gabbro at six different axial strain rates ranging from 10^(-8)/s to 10^(-3)/s. Results show that the strength decreases by about 23% with decreasing strain rate...Uniaxial compression tests have been conducted on Jinan gabbro at six different axial strain rates ranging from 10^(-8)/s to 10^(-3)/s. Results show that the strength decreases by about 23% with decreasing strain rate. The stress level C_0~' /or the onset of dilatancy is constant for six strain rates. When σ_1>C_o~' ε_1 and D increase with decreasing strain rate (?) under a specific stress level.Microscopic observations on the stressed rock samples reveal that the density of microcracks for the samples loaded at low strain rates is higher than that at high strain rates; in addition there are also cracks nearly perpendicular to it, which is responsible for the increase of D value.The creep test under the stress σ_(σ_1>C_0~') confirms that the growth of microcracks in the rock has been time-dependent effects, and the steady-state creep with (?)=constant developed until the rock fails.Summing up the above reslts shows that when σ>C_0~', the constitution law of the rockswill be time-dependent, and the C_0~' value is a limit of the rocks strength.展开更多
The Yishu fault zone consisting of approximately four paraUd faults is an active one. The surface features of quartz grains in gouges from Yishu active fault zone are examined by means of SEM. It is considered that th...The Yishu fault zone consisting of approximately four paraUd faults is an active one. The surface features of quartz grains in gouges from Yishu active fault zone are examined by means of SEM. It is considered that the preserved surface markings on quartz grains may indicate the activity of Yishu fault zone as well as the history of tectonic movements.展开更多
基金Project sponsored by the Joint Seismological Science Foundation
文摘Uniaxial compression tests have been conducted on Jinan gabbro under six different axial strain rates ranging from 10-3s-1 to 10-8s-1(0.8×10-3s-1, 0.6×10-4s-1, 1×10-5s-1, 0.7×10-6s-1, 1.6×10-7s-1 and 2.7×10-8s-1). The stress-strain（σ1—ε1） curve and stress-volumetric strain（σ1—εv） curve thus obtained indicate that, as the
文摘It is important to study the crack growth mechanism, because it effectively demonstrates the dynamic process during the fracturing of materials. We used an ultra-small testing machine and chose a piece of plane glass of 48×28×1 mm3 in size as an experimental sample. A small pre-crack 2 a0, less than 5 mm long, was created in the
基金Project supported by the Joint Seismological Science Foundation
文摘Uniaxial compression tests have been conducted on Jinan gabbro at six different axial strain rates ranging from 10^(-8)/s to 10^(-3)/s. Results show that the strength decreases by about 23% with decreasing strain rate. The stress level C_0~' /or the onset of dilatancy is constant for six strain rates. When σ_1>C_o~' ε_1 and D increase with decreasing strain rate (?) under a specific stress level.Microscopic observations on the stressed rock samples reveal that the density of microcracks for the samples loaded at low strain rates is higher than that at high strain rates; in addition there are also cracks nearly perpendicular to it, which is responsible for the increase of D value.The creep test under the stress σ_(σ_1>C_0~') confirms that the growth of microcracks in the rock has been time-dependent effects, and the steady-state creep with (?)=constant developed until the rock fails.Summing up the above reslts shows that when σ>C_0~', the constitution law of the rockswill be time-dependent, and the C_0~' value is a limit of the rocks strength.
文摘The Yishu fault zone consisting of approximately four paraUd faults is an active one. The surface features of quartz grains in gouges from Yishu active fault zone are examined by means of SEM. It is considered that the preserved surface markings on quartz grains may indicate the activity of Yishu fault zone as well as the history of tectonic movements.
