Experimental Study on Reloading Creep Characteristics of Marble After Unloading–Freezing–Thawing Damage

Abstract

The reloading characteristics of slope projects such as water conservancy and hydropower in cold regions after excavation and unloading are the key to the long-term stability problem of bank slopes in reservoirs. After pre-peak unloading and freeze–thaw, uniaxial gradient loading creep test was carried out with marble, and the unloading creep mechanical behavior of marble under different temperature ranges and different numbers of freeze–thaw cycles was studied. The results show that the temperature range of freeze–thaw and the number of cycles control the reduction of creep damage stress and long-term strength as well as the increasing trend of creep strain of marble, and the time-mechanical response of unloaded marble under the action of freeze–thaw with large temperature difference is more obvious. Based on the traditional Burgers model, a non-constant Burgers model considering freeze–thaw damage was proposed, and the applicability and rationality of the model were verified.