Creep fracture of sandstones

Creep is one of the important properties of rocks and rock masses. But the mechanism and characteristic of rocks in creep has not received the attention it deserves. Sandstones mined from Emei Mountain are investigated and tested by utilizing the three-point bending creep fracture test. A mathematical relation between stress intensity factors and durations of sustained loading for the above specimen is obtained based on the gray prediction theory. The obtained results provide a better understanding of rock fracture under creep.