焙烧铁尾矿制备透水砖试验研究

为了改善尾矿制砖的力学性质，解决尾矿堆积问题，采用焙烧铁尾矿、水泥和粉煤灰为胶凝材料，2.36~4.75 mm粒级铁尾矿为粗骨料，通过搅拌、成型和养护工艺制备透水砖，探究了焙烧铁尾矿用量、水胶比、目标孔隙率和振动时间对透水砖性能的影响，对比未焙烧尾矿制备透水砖的性能。结果表明：① 焙烧尾矿制备透水砖最佳试验条件为：焙烧尾矿掺量60%，振动时间40 s、水胶比0.3，目标孔隙率20%；此时，透水砖抗折强度为3.34 MPa，符合国家标准Rf3.0，抗压强度为15.44 MPa，符合国家标准MU15，透水系数为2.58×10-2 cm/s，符合国家标准A级标准，实测孔隙率为23.41%。② 焙烧尾矿掺量为60%时效果最佳；未焙烧尾矿掺量为50%时效果最佳，抗折、抗压强度分别为3.38 MPa和14.54 MPa，透水系数符合国家A级标准；焙烧尾矿比未焙烧尾矿多替代水泥10%的情况下，力学性能焙烧尾矿透水砖较好，而透水性能则未焙烧尾矿透水砖较好。

Experiment Study on Preparation of Permeable Brick from Roasted Iron Tailings

In order to improve the mechanical properties of tailing brick and solve the problem of tailings storage， the permeable brick was prepared through mixing， molding and curing process preparation， using the roasted iron tailings， cement and fly ash as the gelled material，iron tailings 2.36~4.75 mm as the coarse aggregate. The effect of the addition of roasted iron tailings， water/cement ratio， target porosity and vibration time on the performance of the permeable brick was investigated and performance of the unburned tailings preparation permeable brick was also compared. The results showed that: ① The optimum test conditions for the preparation of permeable brick with roasted tailings are as follow: the addition of calcined tailings of 60%， the vibration time of 40 s， the water/cement ratio of 0.3， and the target porosity of 20%. At the moment， the bending strength of permeable brick is 3.34 MPa in line with the national standard Rf3.0， and the compressive strength is 15.44 MPa in line with the national standard MU15. The permeability coefficient is 2.58× 10-2 cm /s in line with the national standard Grade A standard， and the measured porosity is 23.41%. ② When the addition of the roasted iron tailings is 60%， the best effect is achieved. When the addition of the unroasted tailings is 50%， the best effect is achieved. The bending strength and compressive strength are 3.38 MPa and 14.54 MPa， respectively. The water permeability coefficient conforms to the national Class A standard.In the condition of replacement of addition 10% cement for roasted iron tailing，the mechanical properties of roasted iron tailing is better than that of unroasted tailing，while the permeable coefficient is opposite.