Study on key strata and surface deformation prediction for overburden separation grouting mining in adjacent panel...

Area of Science:

• Mining Engineering
• Geotechnical Engineering
• Rock Mechanics

Background:

• Intensive coal exploitation leads to significant surface deformation, threatening structures and ecological balance.
• Understanding key strata behavior under mining is essential for predicting and mitigating surface impacts.

Purpose of the Study:

• To investigate key strata deformation characteristics during adjacent panel mining with overburden separation grouting.
• To develop a reliable model for predicting surface deformation caused by mining activities.

Main Methods:

• Elastic foundation beam theory and mechanical modeling of key strata.
• UDEC numerical simulations to determine foundation coefficients and their relationship with IPR and panel width.
• Integration of probability integral method and equivalent mining height theory for surface deformation prediction.

Main Results:

• Key strata subsidence decreased quadratically with increasing IPR and increased quadratically with increasing panel width.
• Unequal panel widths induced asymmetric subsidence, which is manageable with controlled IPR.
• The developed prediction model showed high reliability with a field validation deviation of 6.38%.

Conclusions:

• Overburden separation grouting is an effective method for controlling key strata deformation.
• The developed surface deformation prediction model accurately forecasts subsidence, aiding in risk management.
• Maintaining a reasonable IPR is vital for mitigating asymmetric subsidence and ensuring surface stability.