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Abstract According to the conditions of high intensity rockburst and water gushing of the diversion tunnel in Jinping II hydropower station，the application studies of silica fume(SF) and steel fiber reinforced wet-shotcrete were performed. Samples from batching plant were formed by standard moulds and construction site cutting from field sprayed panels. The SF which contained 10% of cement mass was used as an admixture but not a partial cement replacement. The property differences between SF and steel fiber reinforced wet-shotcrete and concrete and between samples of batching plant and field spraying were studied by comparative test. In comparison with the concrete，the SF and steel fiber reinforced wet-shotcrete had the following characteristics by the results： Under the same slum，the water usage per unit volume increased with the incorporation of SF and steel fiber；the flesh concrete became cohesive；the decrease of rebound ratio became larger；the spraying depth increased；the early strength and ratio between splitting tensile strength and compressive strength increased markedly；the flexural toughness and plasticity improved. Through observation and analysis，we found that steel fiber reinforced wet-shotcrete was not suitable to surface permanent supporting of water tunnels，or else，some measures were taken for the surface of the wet-shotcrete. By comparative analysis，it is pointed out that the testing results of samples formed by standard moulds were different from the cubes cutting from field sprayed panels. And the reasons of the differences has been explored. Finally，some problems needing attention are proposed according to actual engineering application，so as to provide certain reference value for engineering practice.
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Received: 22 April 2011
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2011, Vol. 30 
