Experimental Study on Measurement Accuracy of Prediction Index K₁ for Rock Crosscut Coal Uncovering

Abstract:

Coal and gas outbursts are a kind of dynamic phenomena seriously threatening subsurface mining safety in coal mines. A precise prediction of outburst hazard in rock crosscut coal uncovering directly depends on whether or not its prediction index can be accurately determined. Measurement uncertainty reflects the degree of uncertainty of a measured result. In this paper, the authors studied the sources of measurement uncertainty of prediction index K₁ for rock crosscut coal uncovering outburst hazard, built corresponding mathematical model and carried out a great number of laboratory experiments to evaluate the measurement uncertainty of the prediction index K₁ . At a confidence probability of 95%, the expanded uncertainty of the index K₁ is obtained to be 33.3%, far greater than 5% allowed in engineering. To analyze the uncertainty sources, a table of uncertainty components of index K₁ was made, and it’s found through analysis that the mass of desorbed coal sample and the accuracy of pressure sensor are the main factors inducing measurement uncertainty in determination of index K₁ , and corresponding improvement measures were put forward to create conditions for using this index to accurately predict rock crosscut coal uncovering outburst hazard.

• Periodical: Applied Mechanics and Materials (Volumes 249-250)
• Pages: 88-94
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.249-250.88
• Online since: December 2012
• Authors: Yu Jia Chen, Cheng Lin Jiang
• Keywords: Measurement Uncertainty, Prediction Index, Rock Crosscut Coal Uncovering

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