The an thors developed a new composite cement base material by mixing the high tenacity polypropylene (coarse) fiber in plain cement base for the cement-layer-spray technology. By studying the key parameters of the ...The an thors developed a new composite cement base material by mixing the high tenacity polypropylene (coarse) fiber in plain cement base for the cement-layer-spray technology. By studying the key parameters of the fiber dosage, the spray layer thickness, and the fiber reinforced concrete injection time, etc. It is found that the ideal volume ratio of polypropylene (crude) fiber is 0.8% (V/V), and the secondary lining fiber concrete spraying should start when the shrinkage rate is lower than 0.5 mm/d, and the optimal thickness of shotcrete is 120 mm. The supporting effects and the economic benefits were studied using a real project practice, and the result obtained can be a good reference for practical applications of this new supporting material in the future.展开更多
文摘The an thors developed a new composite cement base material by mixing the high tenacity polypropylene (coarse) fiber in plain cement base for the cement-layer-spray technology. By studying the key parameters of the fiber dosage, the spray layer thickness, and the fiber reinforced concrete injection time, etc. It is found that the ideal volume ratio of polypropylene (crude) fiber is 0.8% (V/V), and the secondary lining fiber concrete spraying should start when the shrinkage rate is lower than 0.5 mm/d, and the optimal thickness of shotcrete is 120 mm. The supporting effects and the economic benefits were studied using a real project practice, and the result obtained can be a good reference for practical applications of this new supporting material in the future.