Investigation of the Optimal Layout of the Roadway in Closely Spaced Ultra-Thick Coal Seams Mining with Remaining Coal Pillars

<div>Layout of roadway roof measuring points. (a) Layout of roadway roof measuring points. (b) Layout of section measurement points.</div>

Shock and Vibration

Figure 2: Investigation of the Optimal Layout of the Roadway in Closely Spaced Ultra-Thick Coal Seams Mining with Remaining Coal Pillars 