Modeling of non-linear rheological behavior of hard rock using triaxial rheological experiment

During the reservoir operation process, the long-term security and stability of the bank slope is affected by dynamic response characteristics of its seismic action directly. Aimed at the typical bank slope existing in the actual reservoir environment, an experiment considering reservoir water level fluctuation and soaking-air-drying cyclic water-rock interaction has been designed and conducted while the cyclic loading test was performed in different water-rock cycles. Research results indicate the following: Firstly, in the process of water-rock interaction, the dynamic characteristics of sandstone show evident degradation trend, with the increase of the damping ratio and Poisson's ratio and decrease of dynamic elastic modulus, and the former six water-rock cycle degradation effects are particularly obvious. Secondly, the numerical analog computation analysis of dynamic response in typical bank slope shows that as the water-rock interaction period is increased, the dynamic response of the slope hydro-fluctuation belt zone increases gradually, while the other parts weaken. irdly, under the long-term water-rock interaction process, the hydrofluctuation belt zone gradually becomes a "soft layer" which is sensitive to the earthquake effect and dynamic response, resulting in a direct influence on long-term seismic performance of the bank slope. erefore, it is necessary to make better protection for the bank slope hydro-fluctuation belt zone.

Section: E Cyclic Loading and Unloading Test Schemementioning

confidence: 99%

The Dynamic Response Law of Bank Slope under Water‐Rock Interaction

Zhang

Deng

Wang

et al. 2018

“…Recently, many researchers have focused on studying the influence of the roadway axial principal stress to the plastic analysis and timedependent change in the plastic zone of the deep circular roadway and hope the results will fit the specific reality better. For example, Zhao et al [17][18][19] studied complex elastoviscoplastic behaviors of rock subjected to triaxial stress state and proposed a new EVP creep model to study timedependent change in the plastic zone. In 1985, Yu et al [20,21] put forward a unified strength theory and a double shear strength theory based on the concept of double shear.…”

Section: Introductionmentioning

confidence: 99%

Plastic Failure Analysis of Roadway Floor Surrounding Rocks Based on Unified Strength Theory

Zheng

2018

Taking the whole surrounding rock of an excavation roadway as the research object, the elastoplastic failure mechanics analysis of the surrounding rock body of the excavated roadway under three-directional in situ stresses is carried out by using the knowledge of generalized plane strain problems and unified strength theory, and the equations are derived for the elasticplastic zone stress together with the plastic fracture range of the roadway floor surrounding rock under three-directional in situ stresses. At the same time, by means of the conclusion of mechanical analysis and the results of in situ detection of in situ stress in the Changcun mining area, the stability of the roadway floor surrounding rock was analyzed. e analysis reveals the influence on the stability of the roadway floor surrounding rock between the spatial relationship with the different in situ stresses and the roadway layout; meanwhile, it calculates the range of the plastic failure zone and the stress value of the #1 roadway floor in the S6 mining area of Changcun mine, which provides a reliable theoretical mechanical reference for research on roadway floor heave control technology.

“…After the earthquake observation, however, it is found that under the action of strong ground motion, tunnels may be subjected to extensive deformation or even collapse [1][2][3][4]. e surrounding rock has various pattern fractures, and a series of morphological changes occur in an earthquake [5][6][7][8]. Moreover, the dynamic response of tunnel structure is highly distinct from that of superstructure [9][10][11].…”

Section: Introductionmentioning

confidence: 99%

Parameter Sensitivity of Shallow‐Bias Tunnel with a Clear Distance Located in Rock

Jiang

Wang

Yang

et al. 2018

In order to obtain the seismic internal force response laws of a shallow-bias tunnel with a small clear distance, the reliability of the numerical simulation is verified by the shaking table model test. e parameter sensitivity of the tunnel is studied by using MIDAS-NX finite element software. e effects of seismic wave peak (0.1 g, 0.2 g, 0.3 g, 0.4 g, 0.5 g, and 0.6 g), existing slope angle (30°, 45°, 60°, and 90°), clear distance (1.0 D, 1.5 D, 2.0 D, and 3.0 D), and excitation mode (X direction, Z direction, XY direction, and XYZ direction) on the internal force response law of the tunnel are studied, respectively. e results show that (1) the shear force gradually increases with the increasing of seismic peak. e amplification is different with different measuring points. (2) Under different existing slope-angle conditions, the variation trend of shear force of the tunnel is similar, but the shear force is different. e existing slope has significant effect on the shear force response of the tunnel, and the degree is different with different slope angles. (3) Under the conditions of 1.5 D and 2.0 D, the shear force response of the tunnel is stronger, but the response of other conditions is relatively weak. e tunnel with 1.5 D to 2.0 D clear distance should be avoided. Different excitation modes have a significant effect on the shear force response of the tunnel. (4) Under the same excitation mode, the different excitation directions also have a significant effect on the shear force response. (5) e shear force response of the tunnel crosssection shows nonlinear variation trend. e shear force response is strongest at the arch shoulder and arch foot of the tunnel. e research results provide a useful reference for the design of antishock and vibration resistance of the tunnel.