Proactive intervention depressurization control for pre-mining roof fall and mining impacts.

Area of Science:

• Mining Engineering
• Geotechnical Engineering
• Rock Mechanics

Background:

• Roof fall in return air roadways poses significant challenges in coal mining operations, particularly when passing through goaf areas.
• Understanding the causes of roof fall, such as high static loads and mining pressure, is crucial for effective control.

Purpose of the Study:

• To analyze the characteristics and causes of roof fall along the rib of the goaf in the Lijiahao coal mine.
• To propose and evaluate an early intervention pressure relief control technology for surrounding rock control.

Main Methods:

• On-site investigations and numerical simulations were conducted to analyze roof fall characteristics.
• A numerical model based on the Mohr-Coulomb criterion was established to identify influencing factors.
• An early intervention pressure relief control technology centered on "proactive avoidance" was developed and implemented.

Main Results:

• The deformation of surrounding rock is influenced by static loads, mining pressure, rock properties, and pressure relief effects.
• The optimal timing for intervention is when the working face is 20m from the roof fall area, with an avoidance roadway staggered 20m.
• The proactive intervention pressure relief technology reduced surrounding rock deformation by approximately 11%.

Conclusions:

• Early proactive intervention pressure relief technology is effective in reducing roadway surrounding rock deformation.
• The developed "proactive avoidance" strategy provides a practical and effective solution for controlling roof fall in coal mines.
• Resuming the use of the original roadway after passing through the avoidance roadway ensures economic benefits while maintaining safety.