Shorter Mine Boreholes More Effectively Reduce Rock Stress
Study shows that 30 m boreholes outperform 50 m variants at mitigating rockburst risks in the 1305 working face.
Updated on Oct. 28, 2026 in Geology
Researchers investigating pressure relief methods at the 1305 working face of a mine found that 30 m deep boreholes effectively reduced rock stress. Conversely, 50 m boreholes were found to inadvertently increase stress and displacement, according to the research-stage study.
Why it matters
Pressure relief schemes are vital for preventing rockbursts, sudden failures of brittle rock that endanger miners. Understanding how borehole depth influences stress distribution is critical for optimizing safety protocols in underground mining operations.
The study utilized numerical simulation to model pressure relief, comparing 30 m and 50 m borehole depths. Field validation confirmed that while the 30 m depth successfully mitigated deformation, the 50 m scheme generated overlapping secondary pressure zones that exacerbated rock instability.
The details
Pressure relief boreholes are conduits drilled into coal seams to allow internal gas and stress to dissipate, preventing the sudden, high-energy rock failure known as a rockburst. The study suggests that deeper 50 m boreholes inadvertently transfer stress to the surrounding coal pillar rather than relieving it. The 30 m depth remains the more effective configuration for stabilizing the immediate working face, as determined through a combination of predictive simulation and on-site testing.
Timeline
October 28, 2026: The research findings were published.
The Tech Race
This study challenges standard assumptions regarding borehole depth in pressure relief programs used to prevent rockburst accidents. It marks a critical refinement in mining safety engineering by demonstrating that deeper interventions do not necessarily equate to higher safety margins.
Mining engineers and safety officers can utilize these findings to recalibrate pressure relief drilling patterns at active working faces. The study serves as a technical benchmark for current safety protocols, suggesting that increasing borehole depth without site-specific simulation may increase geological risk.
The takeaway
Effective pressure relief is not always a function of depth, as demonstrated by the counterproductive results of 50 m boreholes in this study. Mine safety planners should watch for future simulation-based safety studies that quantify rock stress displacement in similarly structured working faces.
Further reading
Learn more about structural earth dynamics in our Geology section.
More information
Review the technical findings in the complete peer-reviewed research article.
