To study the characteristics of quiet period acoustic emission (AE) during rock failure process, models with an abnormal elastic modulus were established based on PFC2D. The calibration mesoscopic parameters was performed by macroscopic mechanical granite samples obtained in uniaxial compression tests. An area 2 × 100 mm2 set at center model and had two to six times normal area. evolution law c...

To research the internal load transfer behavior and failure mechanism of a bird’s nest anchor cable anchoring structure based on pull-out test, bond-slip model is established basis statistical damage theory, distribution formula shear stress at anchorage agent–rock interface deduced. Combined with theoretical analysis, pulling out test particle flow code (PFC) numerical simulation as well axial...

This study is aimed at investigating the excavation damage characteristics of surrounding rock in Jinping deeply buried marble tunnels, China. According to acoustic detection results tunnel cross-sections under condition boring machine (TBM) obtained on site, PFC microscopic parameters Types II/III were simulated and calibrated through PFC2D program. In doing so, deeply-buried sections diversio...

The recovery of top coal in the caving face directly impacts efficiency mining resources. geological conditions and parameters are well known to be significant influences on coal. This study focused 9-301 working face, which is located a thick seam with large dip angle. seam’s angle, direction, mode interval were analyzed using PFC2D simulation. Field trials also carried out. results numerical ...

Hydraulic fracturing of a roof can attenuate the strong mineral pressure and stress transfer by creating series parallel artificial fractures in it, different forms hydraulic have effects on attenuation effect coal rock system. In this regard, study investigated influence law pre-cracks mechanical properties rock–coal combined body through PFC2D numerical simulation, following conclusions were ...

When the tunnel and underground engineering construction encounters water-rich soft broken surrounding rock, it is very easy to occur serious disasters such as mud inrush, water inrush collapse, threatening safety of construction. Taking ultracataclasite stratum exposed by 4th branch Xianglushan Tunnel in Central Yunnan Water Diversion Project an example, this has strong compactness, weak perme...

In recent years, an international consortium of research organizations conducted investigations at the Chicxulub Crater in Yucatan, Mexico, to better understand crater’s formation mechanisms and effects produced by impact asteroid that is hypothesized have caused one major life extinctions on Earth. This study aims reproduce asteroid’s mechanics matching computer simulations obtained with use d...

In order to guarantee perpendicularity of rotary cast-in-place pile in Karst areas, filling, like sand, etc., is commonly used between the inner steel casing and outer sleeve; while sleeve pulled out or a vertical load applied on top pile, sand will move, contact, push against each other, which leads recrushing; therefore, shear characteristics secondary breakage are meaningful problem study wi...