Abstract Low rate of penetration (ROP) and high drilling cost are the key problems that encountered in hot dry rock (HDR) geothermal resources exploitation utilization. Plasma channel (PCD) is a potential technology which has advantages rock-breaking efficiency ROP. A detailed understanding PCD essential to optimize electrical parameters bit structure. Therefore, this paper uses probabilistic e...

Abstract Brittleness is a crucial parameter of rock mass and the key indicator in engineerings, such as rockburst prediction, tunnelling machine borehole drilling, hydraulic fracturing. To solve problem using present brittleness indexes, existing indexes were firstly summarised this paper. Then, index (BL), which considers ratio stress drop rate increase peak stress, was proposed. This new has ...

Numerical testing is an ideal method in the research on mechanical behaviors of jointed rock. However, there are few systematic studies focused comparison between two-dimensional (2D) and three-dimensional (3D) simulation effects rock behaviors, particularly those In this paper, a particle flow model was established by utilizing PFC2D PFC3D to represent materials, (especially rock) (uniaxial co...

Under the action of dynamic loadings such as earthquakes and volcanic activities, mechanical properties gas-hydrate-bearing sediments will deteriorate, leading to a decrease in stability hydrate reservoirs even inducing geological disasters submarine landslides. In order study effect loading on sediments, triaxial compression tests numerical specimens were carried out by using particle flow cod...

In this work, the interaction between the semi-circular space and the neighboring joint with and without the presence of rock bolts was investigated using the particle flow code (PFC) approach. For this purpose, firstly, the calibration of PFC was performed using both the Brazilian experimental test and the uniaxial compression test. Secondly, a numerical model with the dimension of 100 m...

Nowadays, the development and utilization of more engineering construction are closely related to granite. However, many granite rock masses in Qingdao contain natural hole defects, which have a great impact on mechanical properties It may even cause instability surrounding safety accidents. Therefore, this paper, we discuss influence diameter stability tunnels. Uniaxial compression experiments...

Bulk gangue is a common backfill material in solid mining. After backfilling into the goaf, bulk serves as main body to bear load of overlying strata, and its deformation resistance key factor affecting quality. In this study, laterally confined compression test broken was designed, compaction characteristics specimens under different loading rates were studied, acoustic emission (AE) energy an...

The limestone stratum has well-developed rock fissures and abundant groundwater. Under extreme rainstorm conditions, tunnel surrounding seepage is serious especially. In order to reveal the grouting diffusion mechanism of karst fractured mass realize effective water plugging, in this paper, basic mechanical parameters are obtained by laboratory triaxial test, porosity distribution nuclear magne...