骨料堆积密实度对充填体强度影响的规律研究  

Study on the Law of Influence of Aggregate Packing Density on the Strength of Filling Body

作　　者：张超 胡亚飞 王延春 顾金钟 ZHANG Chao;HU Yafei;WANG Yanchun;GU Jinzhong(State Key Laboratory of Nickel and Cobalt Resources Comprehensive Utilization,J inchang,Gansu 737100,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]镍钴资源综合利用国家重点实验室,甘肃金昌市737100 [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》2019年第8期96-100,共5页Mining Research and Development

基　　金：国家“十二五”科技支撑计划项目(2012BAB08B02);国家自然科学基金资助项目(51374034,51304011)

摘　　要：骨料堆积密实度是孔隙率、骨料粒径、级配关系的综合反映。为研究骨料堆积密实度对充填体强度影响的规律,以废石集料和风砂为骨料,开展了堆积密实度试验;以水泥掺量、水灰比、质量浓度为变量,以单轴抗压强度为考察指标,开展了骨料密实度对充填体强度影响的试验研究。结果表明:混合料堆积密实度对充填强度有较大影响。在实验范围内,随着废石集料的增加,混合料堆积密实度呈"拱形"先增大后减小,当砂石比为5∶5时,密实度达到最大值为0.724,此时可充分发挥混合料的强度效应,此后废石占比每提高10%,充填体7d和28d强度分别降低12.5%和11%。充填体强度与水泥掺量和质量浓度成正相关,而与水灰比成负相关;满足7d和28d强度分别为2.5MPa和5MPa的前提下,最佳水泥掺量为240kg/m^3,最佳水灰比为1.6,最佳砂石比为5∶5,最佳质量浓度为79%。Aggregate packing density is a comprehensive reflection of porosity,aggregate size and gradation.In order to study the law of the influence of aggregate packing density on the strength of the filling body,the packing density test was carried out by taking waste rock aggregate and wind sand as aggregate.Taking cement content,water-cement ratio and mass concentration as variables and uniaxial compressive strength as an investigation index,the experimental study on the influence of aggregate density on filling strength was carried out.The results showed that the packing density of the mixture had a great influence on the filling strength.In the experimental range,with the increase of waste rock aggregate,the packing density of the mixture increased first and then decreased.When the ratio of sand to gravel was 5∶5,the density reached a maximum value of 0.724.At this time,the strength effect of the mixture can be fully exerted.After that,each additional of 10%at the proportion of the waste rock,the strength of the filling body at 7 dand 28 dwas accordingly decreased by 12.5% and 11%,respectively.The strength of the filling body was positively correlated with the cement content and mass concentration,but was negatively correlated with the water-cement ratio.Under the premise that the strength of 7 d,28 dwas 2.5 MPa and 5 MPa respectively,the optimum cement content was 240 kg/m^3,the best water-cement ratio was 1.6,the optimum sand ratio was 5∶5,and the optimum mass concentration was 79%.

关 键 词：堆积密实度 胶结充填 配合比 强度效应 

分 类 号：TD853.34[矿业工程—金属矿开采]