Enhancing the SCC Resistance of the Anchor Steel with Microalloying in a Simulated Mine Environment.

This work explored a new idea for enhancing the resistance to stress corrosion cracking (SCC) of mining anchor steel through microalloying. Microalloyed anchor steels with Nb, Cu, Ni, Sb, and C were prepared through vacuum smelting and hot rolling. Electrochemical measurements, slow strain rate tensile (SSRT) tests, and fracture morphology observations were used to study the electrochemical and SCC behavior in the simulated mine environment.

Experimental and numerical investigation of the interaction between blast wave and pre-crack in a defected material: publisher's note.

This publisher's note corrects the affiliation section in Appl. Opt.58, 9718 (2019)APOPAI0003-693510.

Explosion wave and crack field of an eccentric decoupled charge.

To investigate the characteristics of the explosion damage from an eccentric decoupled charge, the rock-breaking mechanism of an eccentric decoupled charge is revealed from the perspectives of the explosion wave field and crack field through theoretical and experimental analyses. The ratio of the maximum to minimum pressure on an eccentric decoupled hole wall increases exponentially with an increase in the decoupling coefficient, but it does not change with a change in the explosive density or explosive detonation velocity. The explosive energy on the eccentric charge side has a certain accumulation effect, the velocity of the reflected shock wave at the blasthole wall is greater than that of the incident shock wave, and the incident velocity of the explosion wave on the eccentric side is greater than that on the non-eccentric side.

Experimental study on the effect of defect curvature on the impact fracture behavior of structures using the real-virtual caustics method.

Defects have significant influence on the impact fracture behavior of structures. In this paper, the real-virtual caustics method is used to study the impact fracture behavior of structures with elliptical arc defects under impact loading of the drop hammer, and the impact loading process is simultaneously analyzed. The research results show that impact loading of the drop hammer in this experiment is a multi-period dynamic loading process, and the fracture of specimens under impact loading of the drop hammer is an energy-controlled process.

Design and application of a comprehensive experimental system for real imaging-virtual imaging of dynamic caustics.

On the basis of the principle of caustics, a comprehensive experimental system for real imaging-virtual imaging was designed and established and then applied to dynamic fracture mechanics experiments. An explosion load experimental system was used to investigate the interaction between blast stress waves and prefabricated cracks. The virtual image information of the caustic spot of the crack tip under the radial compressive stress of the explosive load was captured and quantified.

Experimental and numerical investigation of the interaction between blast wave and precrack in a defected material.

This study uses a cracked medium to study the interaction mechanism between blast waves and the precrack. The experimental results show that the compressive phase of the dilatational wave would cause the opened precrack to close with a negative sign of stress intensity factor $K_{\rm I}^d$KId, while the tensile phase of the dilatational wave attributes to the precrack opening and increases the crack velocity. However, the shear wave tends to make crack initiation at mixed-mode I/II fracturing by increasing the dynamic stress intensity factor $K_{\rm II}^d$KIId.

Deformation mechanisms in a coal mine roadway in extremely swelling soft rock.

The problem of roadway support in swelling soft rock was one of the challenging problems during mining. For most geological conditions, combinations of two or more supporting approaches could meet the requirements of most roadways; however, in extremely swelling soft rock, combined approaches even could not control large deformations. The purpose of this work was to probe the roadway deformation mechanisms in extremely swelling soft rock.