摘要
铁尾矿大量堆存不仅造成环境污染而且存在地质灾害风险,将其用作膏体充填材料骨料,能够解决尾矿危害并保证矿山地下采场的安全稳定。通过开展相关试验,研究了本溪歪头山铁尾矿基本性质,发现其比重大、细颗粒含量少且级配不良,不适合单独作为膏体充填材料骨料。通过试验研究粉煤灰基本性质,选择将其作为掺合料,掺量由0开始以2.5%的梯度升高至15%,通过坍落度试验确定料浆质量浓度为72%,混合各材料制备膏体充填材料。试验研究了不同粉煤灰掺量下充填材料的坍落度、抗压强度、孔隙率和吸水率的变化。结果表明:随着粉煤灰掺量的增加,料浆坍落度由180.2 mm增加至240.2 mm,试件孔隙率先减小后略微上升,吸水率提升,28 d无侧限抗压强度达1.359 MPa。研究表明掺入粉煤灰可以提升膏体充填材料流动性和强度,但粉煤灰掺入量以不多于固体质量的12.5%为宜,该研究成果可为其他金属矿山改良充填结构提供理论支持。
The large storage of iron tailings not only causes environment pollution,but also has the risk of geological disasters.It can be used as paste filling material aggregate,which can solve the harm of tailings and ensure the safety and stability of underground stope.The Waitoushan iron mine adopts filling method.The filling material is composed of iron tailings,cement and water and the filling slurry has a mass concentration of 68%,which belongs to cemented filling with low-concentration whole tailings.Due to the low mass concentration of filling slurry,the whole tailings of iron tailings are coarse.Fine particles such as cement in the slurry are easily lost,which are not only waste cementing materials and affect the strength of the filling body,but also seriously pollute the underground environment.The filling material composition is fixed,and other admixtures and additives are not added,so the filling structure of the mine is single.Aiming at the problems of waste of filling materials and single filling structure in Waitoushan iron mine,the basic properties of Waitoushan iron tailings were studied by relevant tests.The test shows that the iron tailings have a large proportion,a small content of fine particles and poor gradation,so it is not suitable as paste aggregate alone.The fly ash was selected as admixture to supplement the fine particles in the iron tailings.The content of fly ash increased from 0 to 15%in a gradient of 2.5%,and the mass concentration of slurry was 72%,the paste filling material was prepared by mixing all materials.The slump,compressive strength,porosity and water absorption of filling materials with different fly ash content were tested.The results show that with the increase of fly ash content,the slump of slurry increases from 180.2 mm to 240.2 mm,the porosity decreases first and then slightly increases,and the water absorption rate increases.The unconfin compressive strength of filling material specimen could reach 1.359 MPa in 28 days.The results show that the fluidity and unconfined co
作者
海龙
程同俊
徐博
赵鑫
HAI Long;CHENG Tongjun;XU Bo;ZHAO Xin(School of Mechanics and Engineering,Liaoning Technical University,Fuxin 123000,Liaoning,China)
出处
《黄金科学技术》
CSCD
2022年第5期724-732,共9页
Gold Science and Technology
关键词
铁尾矿
全尾砂
膏体充填
粉煤灰
性能改良
iron tailings
full tailings
paste filling
fly ash
performance improvement
