掺复合功能掺合料快速修补混凝土的试验研究

以优质粉煤灰和硅灰复合粉体为基材外掺少量激发剂配制而成的复合功能掺合料(CUFG)是一种新型水泥混凝土路面快速修补材料。采用42.5级普通硅酸盐水泥,单方水泥用量315~360 kg/m3,掺入20%~30%复合功能掺合料,可配制出24 h抗压强度大于20 MPa,24 h抗折强度大于3.5 MPa;28 d抗压强度大于50 MPa;28 d抗折强度大于7.0 MPa的快硬高早强混凝土,满足24 h开放交通所需的最低强度指标要求,且后期强度也有较大的提高。CUFG的掺入提高了快速修补混凝土(RRC)早期和后期的折压比,降低了混凝土的干缩程度,有利于提高快速修补混凝土的抗裂性能。掺CUFG快速修补混凝土的抗氯离子渗透能力较强,同时具有优异的耐磨性能。

The experimental study of rapid repair concrete with CUFG

Composite functional admixture with fly ash and silica fume as matrix and a small amount of activator(CUFG) is a new kind of rapid repair material for cement concrete pavement.The rapid hardening and high early strength concrete prepared with 315-360 kg/m3 strength grade no less than 42.5 ordinary Portland cement and CUFG replacing 20%-30% of cement can meet the minimum strength index demands of opening to traffic within 24 h,the compressive strength and the flexural strength is higher than 20 MPa and 3.5 MPa,respectively at 24 h;the compressive strength and the 28 d flexural strength is higher than 50 MPa and 7.0 MPa,respectively at 28 d.At the same time,the long term strength increase steadily.CUFG increases the ratio of flexural strength and compressive strength of rapid repair concrete(RRC),decreases the dry shrinkage rate of rapid repair concrete.The cracking resistance of rapid repair concrete with CUFG is improved.Rapid repair concrete with CUFG has stronger Cl-permeability resistance and better abrasion-resisting property.