Hysteresis and attenuation of saturated rocks under cyclic loading
循环荷载下饱和岩石的滞后和衰减

We analyze hysteresis phenomena such as stress-strain loop, "X" shape of instantaneous modulus and Poisson's ratio, and effect of strain amplitude on attenuation of saturated rocks under cyclic loading by experiments of fluid saturated sandstones and marbles. We think that the attenuation of a rock is in proportion to the strain amplitude of the applied cyclic loading, and the b value of attenuation is a measurement to a saturated rock's attenuation under cyclic loading. We discuss the possible micro mechanisms of attenuation and hysteresis at low frequencies by the macro behavior of saturated rocks in uniaxial stress cycling tests. The flow of porous fluid may play an important role in attenuation and hysteresis of a porous rock, and both the grain contact adhesion and stick-slip friction might be the causes of a porous saturated rock's hysteresis and attenuation in high stress and low frequency cycling tests.