不同粗骨料对膏体强度性能的影响及配比优化

Effect of Different Coarse Aggregates on the Performance of Paste Strength and Its Formulation Optimization

云南某铅锌矿水淬渣产量逐渐降低,难以满足充填需求,亟需寻求新型粗骨料。以该矿全尾砂、机制砂、水淬渣为试验材料,采用正交设计法,研究料浆质量浓度、灰砂比、粗骨料含量以及粗骨料种类对膏体抗压强度的影响。基于最大密度曲线理论和贝雷法,从密实度和骨架结构两方面对混合物料级配进行评价,并对全尾—机制砂进行物料配比优化。研究表明:料浆质量浓度和灰砂比是抗压强度的主要影响因素,粗骨料含量的影响作用较小;相同条件下,全尾—水淬渣膏体抗压强度最大,全尾砂膏体次之,全尾—机制砂膏体抗压强度最小;全尾—机制砂膏体级配不良,密实度小于全尾—水淬渣和全尾砂膏体,且没有形成稳定骨架,再加上机制砂含泥量较高,导致全尾—机制砂膏体抗压强度最小。物料配比优化后,机制砂添加量为42.78%,全尾砂添加量为57.22%,达到较大密实度的同时又形成了稳定的骨架结构,有利于提高膏体抗压强度。

The output of granulated slag of a lead-zinc mine in Yunnan is gradually decreasing,and it is difficult to meet the filling demand.Therefore,it is urgent to find a new type of coarse aggregate.Using the unclassified tailings,manufactured sand and granulated slag of the mine as experimental materials,the orthogonal design method was used to study the influence of slurry mass concentration,cement-aggregate ratio,coarse aggregate content and coarse aggregate types on the compressive strength of the paste.Based on the maximum density curve theory and Bailey method,the mixture gradation is evaluated from the aspects of density and skeleton structure,and the material ratio of the unclassified tailing-manufactured sand is optimized.The results show that the slurry mass concentration and the cement-aggregate ratio are the main influencing factors of the compressive strength,and the influence of the coarse aggregate content is small.Under the same conditions,the compressive strength of the unclassified tailing-granulated slag paste is the largest,followed by unclassified tailing paste,and the unclassified tailing-manufactured sand paste has the lowest compressive strength.The gradation of the unclassified tailing-manufactured sand paste is poor,and smaller density,unstable skeleton structure,and higher mud content together lead to the smallest compressive strength of the unclassified tailing-manufactured sand paste.After the material ratio is optimized,the amount of manufactured sand added is 42.78%,and the amount of full tailings added is 57.22%,which achieves a large density while forming a stable skeleton structure,which is conducive to the improvement of the compressive strength of the paste.