纳米材料在喷射混凝土中的应用研究

Study on the Application of Nano Material in Shotcrete

在成都地铁18号线5标龙泉山隧道C25喷射混凝土中掺入了10%的HB7-2W型纳米材料以等量替代水泥,可将混凝土1 d强度由5 MPa提高至10 MPa以上,28 d的抗压强度提高30%,综合回弹率降低60%以上,施工工效提高27.4%;喷射混凝土过程中的粉尘浓度降低幅度达到47%;耐久性方面,抗冻等级达到F200以上,抗渗等级达到W8,抗硫酸盐侵蚀等级达到KS50,电通量仅为400 C,为地铁洞挖隧道支护提供了一种高强、高效、节约成本的新型材料。

When 10%HB7-2W nano material is added in C25 shotcrete used in Longquanshan Tunnel of Chengdu Metro Line 18,to replace an equivalent quantity of cement,1-day strength of concrete is increased from 5MPa to more than 10 MPa,the 28-day compressive strength is increased by 30%,the comprehensive rebound rate of shotcrete is reduced by more than 60%,the construction efficiency is increased by 27.4%,and dust density during shotcreting is reduced by 47%.In terms of durability,the frost resistance grade is above F200,the impermeability grade is W8,the sulfate resistance grade is KS50,and the electric flux is only 400C.It provides a new material with high strength,high efficiency and cost saving for the support of subway tunnel.