Alongside mining depth of mine continuing,roadway support displays out soft rocks feature,anchor way of bolt must expand from end bolt to long bolt and all bolt.

 
  • 隨著(zhù)礦井采深的不斷加大,巷道支護表現出軟巖支護的特點(diǎn),錨桿錨固方式由端錨逐步向加長(cháng)錨、全錨方向發(fā)展。
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