关键词: 特细砂, 喷射钢纤维混凝土, 砂率

Abstract: Aiming at the status quo of lacking natural sand in Chongqing area, the performance of steel fiber reinforced sprayed concrete （SFRSC） with superfine sand mixing with the machine-made sand and its application to the tunnel construetion are studied. It is shown that compared with the properties of SFRSC with natural coarse sand, SFRSC with mixed sand（ the sand ratio 54% - 58% ）exhibits similar performance, which is made of mixing superfine sand with machine-made sand in accordance with the 2 ： 3 ratio of sand mixed. The fineness modulus of the superfine sand mentioned above is 1.2 and 3.5 respectively. The application in practical engineering indicates that it is obviously advantageous for SFRSC to be used at the early stage of lining construction in tunnel engineering.

Key words: superfine sand , steel fiber reinforced sprayed concrete （SFRSC） , sand ratio ;