Experimental loading system and method for studying the interaction between blast stress wave and moving crack

Abstract

The invention discloses an experiment loading system and method for researching interaction of explosion stress waves and moving cracks. A drop hammer freely falls and hits an impact head, and the impact head applies impact loads on a test piece, so that the test piece is subjected to crack initiation to generate moving cracks; an electric signal is generated when the drop hammer makes contact with the impact head, the electric signal is transmitted to an automatic tracking synchronous machine through a signal line, and the automatic tracking synchronous machine sends out triggering signals to a multi-channel pulse igniter; the interval between the time when the automatic tracking synchronous machine receives the electric signal and the time when the automatic tracking synchronous machine sends out the triggering signals can be set in advance; the multi-channel pulse igniter discharges immediately after receiving the triggering signals, discharging is performed at the tip of an initiation probe connected with an initiation line to ignite explosive in an explosive bag, and explosion stress waves are generated; the experiment loading system ignites one or more explosive bags at different periods of moving crack expansion, the explosion time interval of multiple explosive bags can also be set artificially, and different experiment requirements can be met.

Description

technical field [0001] The invention relates to a blasting test experimental system in the field of fracture mechanics research, in particular to an experimental loading system and method for studying the interaction mechanism of blast stress waves and moving cracks. Background technique [0002] Drilling and blasting technology is widely used in open-pit mines and deep mines, road construction, tunnel and shaft excavation. The blasting action is an instantaneous process of high temperature, high pressure and high speed. Most of the blasted medium-rock materials are formed by natural deposition for hundreds of millions of years, and there are randomly distributed pores and cracks of different orders; at the macro level, natural rock mass is a heterogeneous, non-elastic, and anisotropic material. Due to geological tectonic movement and other stresses, natural rock mass is cut by various geological structural planes—joints, fissures, and faults. Due to the existence of a lar...

AI Technical Summary

Problems solved by technology

Due to the precision of pyrotechnics and the delayed detonation technology, it is inevitable that some blastholes will be detonated first and some blastholes will be detonated later. In this way, there must be the interaction between the cracks generated by the blast holes first and the stress waves generated by the blast holes later. Issues such as interpenetration of explosive main cracks

However, there are relatively few experiments and studies on the interaction between blast stress waves and moving cracks.

Images