Study on Dynamic Evolution of Roof Crack and Support Timing of Secondary Tunneling for Large Section Open-Off Cut in Deep Mines

<div>Coal mine location and the roadway site: (a) the LODM I-I section; (b) enlarged drawing of the 5202 LODM; (c) the LODM and working surface layout drawing of the research site; (d) location of the research site.</div>

Advances in Civil Engineering

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Figure 1

Figure 1: Study on Dynamic Evolution of Roof Crack and Support Timing of Secondary Tunneling for Large Section Open-Off Cut in Deep Mines 