外加料对尾砂湿喷混凝土强度影响的试验研究  

Experimental Study on the Influence of Additives on the Strength of Wet Shotcrete with Tailings

作　　者：吴炜 胡亚飞 陈建新 孟科 WU Wei;HU Yafei;CHEN Jianxin;MENG Ke(Guizhou Jinfeng Mining Limited,Guiyang,Guizhou 550023,China;Key Laboratory of Ministry of Education for High-efficient Mining and Safety of Metal,University of Science and Technology Beijing,Beijing 100083,China)

机构地区：[1]贵州锦丰矿业有限公司,贵州贵阳550023 [2]北京科技大学金属矿山高效开采与安全教育部重点实验室,北京100083

出　　处：《矿业研究与开发》2020年第5期84-88,共5页Mining Research and Development

基　　金：国家自然科学基金资助项目(51374034、51304011).

摘　　要：针对分级尾砂湿喷混凝土强度低的缺点,开展了配合比正交试验,以硅粉、粉煤灰、矿渣粉和MF525掺量为变量,以分级尾砂湿喷混凝土强度为考察指标,开展了外加料对分级尾砂湿喷强度的影响规律研究。结果表明:矿渣粉和硅粉是对分级尾砂湿喷强度影响最大的两个因素。在试验范围内,矿渣粉掺量小于75kg时,混凝土强度增长缓慢,当掺量超过75kg时,混凝土强度开始明显增长;硅粉对混凝土7d强度的作用效果最明显,而对28d和56d的作用效果相对减弱;随着MF525掺量的增加,该外加剂表现出了抑制强度增长的特性;粉煤灰掺量超过150kg时,28d和56d强度基本停止增长,56d强度总体上比28d强度提高1MPa,说明粉煤灰可以提高混凝土的后期强度。最终得到外加料最佳配比为矿渣粉105kg、硅粉50kg、粉煤灰200kg、MF525 100g。Aiming at the low strength of wet shotcrete with graded tailings,the orthogonal test of mix proportion was carried out.Taking the contents of silica powder,fly ash,slag powder and MF525 as variables and the strength of wet shotcrete with graded tailings as inspection index,the influences of additives on the strength of wet shotcrete with graded tailings was studied.The results showed that the slag powder and silica powder were the two factors that had the greatest influence on the strength of wet shotcrete with graded tailings.In the experimental range,when the content of slag powder was less than 75 kg,the strength of shotcrete increased slowly;when the content of slag powder was more than 75 kg,the strength of shotcrete began to increase obviously.The effect of silica powder on the strength of shotcrete in 7 dwas the most obvious,but its effects on strength in 28 dand 56 dwere relatively weak.With the increase of MF525 content,the additive showed the characteristics of inhibiting the growth of strength.When the content of fly ash was more than 150 kg,the strength in 28 dand 56 dbasically stopped growing,and the strength in 56 dwas 1 MPa higher than that in 28 d,which showed that the fly ash can improve the later strength of concrete.The best mixing proportion of additives was cement of 440 kg/m3,water-cement of 0.45,sand-stone of 2.33(7∶3),and water reducing agent of 1%.

关 键 词：外加料 尾砂湿喷混凝土 正交试验 

分 类 号：TD853[矿业工程—金属矿开采]