Effect of cyclic wetting and drying on the pure mode II fracture toughness of sandstone

Experimental Study on Mixed Mode Fracture Behavior of Sandstone under Water–Rock Interactions

“…These failures are strongly associated with water-rock interactions, such that many geological disasters like earthquakes, debris flow, landslides, and ground subsidence, have occurred in recent years. Water-rock interactions can significantly deteriorate the physical and mechanical properties of rocks, and they have been identified as one of the significant factors influencing the stability and safety of structures in rock-soil engineering and tunnel engineering [1][2][3].…”

“…The mechanical parameters in the aforementioned studies were mainly compressive strength, cohesion resistance, tensile strength, shear strength, and so on. However, studies on the fracture mechanical properties of the rocks affected by periodic water-rock interactions and long-term immersion are scarce [1][2][3]9,15,36]. It has not yet been incompletely understood how the mixed mode fracture behavior of rocks is influenced by periodic water-rock interactions and long-term immersion.…”

Mixed mode fracture analysis of CCBD specimens based on the extended maximum tangential strain criterion

“…However, some research results indicated that there were huge differences between the test results and the predictions according to the abovementioned fracture criteria. [6][7][8][9][10] This is probably because all those criteria only consider the influence of stress intensity factors (SIFs) and ignore the higher order terms of Williams' series expansion 11 (such as T-stress) in estimating the crack initiation conditions. Many researchers have used the T-stress to modify the conventional fracture criteria for improving the theoretical predictions.…”

Damage Features of Altered Rock Subjected to Drying-Wetting Cycles

“…e rock samples were subjected to 1,5,8,15, and 20 drying and wetting cycles in di erent hydrochemical environments. e test design is shown in Figure 3.…”

“…Many valuable achievements about the influence of drying and wetting cycles to various rocks have been studied by domestic and foreign researchers. Liu and Deng et al [6,7] examined the deterioration laws of sandstone under waterrock interaction, including the changes of compressive strength and rheological properties; Hua et al [8] studied the fracture toughness of sandstone subjected to cyclic wetting and drying; the swelling behavior of volcanic rocks or mudstone and stabilized expansive soils has been studied by Vergara et al, Doostmohammadi et al, and Rao et al, respectively [9][10][11]; the effects of acid rain on the mechanical properties and the stability of reservoir slope slump under the condition of acid rain were examined by Liu et al [12][13][14]; Zhao et al [15] have investigated the change laws of tensile strength of sandstone with low clay mineral content; Liu et al [16] have studied the crack growth mechanism, especially subcritical crack under water-rock interaction; and Saleh-Mbemba et al [17] examined the water retention of tailings behavior. As for altered rock, the hydromechanical properties of altered rock have been analyzed by Wang et al [18], and Kohno et al and Chen et al [19,20] have studied the relations between point load strength index and UCS (uniaxial compressive strength) of hydrothermally altered soft rock.…”