Theory and test of underground explosions: Coupling rule between cratering and ground shock

Abstract

Calculating the parameters of the ground shock induced by an underground explosion is a complex energy coupling problem. It is difficult to establish a unified ground shock coupling law from limited test data. This paper summarizes the research results obtained at home and abroad and systematically analyzes the coupling mechanism of craters formed by an underground explosion and the ground shock. The differences between the concepts of “closed-explosion critical depth” and “equivalent closed-explosion critical depth” are clearly explained. The spreading of the ground shock energy is attributed to the explosive expansion of the air cavity, revealing a linear relationship between the volume of the cavity region (or the volume of the crack region) and the ground shock energy associated with the underground explosion. The proportionality factor is related to the mechanical properties of the medium and is independent of the magnitude of the explosion equivalent. Based on this, a theoretical calculation formula and conversion method for the ground shock coupling coefficient were established. Explosion tests were conducted in clay and Plexiglass under varying burial depths. The test results were consistent with the theoretically calculated results. Our study provides a theoretical basis for the design of explosion-resistant structures in underground engineering.

Keywords

Underground explosion / Ground shock coupling / Coupling coefficient / Equivalent closed explosion / Experimental study

CRediT authorship contribution statement

Wei Guo: Conceptualization, Methodology, Investigation, Data curation, Writing - original draft. Jie Li: Methodology, Investigation, Data curation, Writing - original draft. Benjun Shi: Investigation, Data curation, Writing - original draft. Tianhan Xu: Investigation, Data curation, Writing - original draft. Xiaohui Xu: Investigation, Data curation. Gan Li: Investigation, Data curation. Jie Shi: Investigation, Data curation.

Declaration of competing interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Acknowledgment

This research was funded by the National Natural Science Foundation of China (Grant No. 52279120). Thanks for the MJEditor (www.mjeditor.com) for its linguistic assistance during the preparation of this manuscript.

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