As part of an extensive research program exploring the potential benefits of using air-entraining admixtures in mine backfill, the experimental study presented in this paper investigates the effect of cement and entrained air dosages on mine backfill unconfined compressive strength (UCS), fresh density, and dry density. Backfill specimens were prepared using silica sand, normal Portland cement, water, and an entrained air admixture. An experimental design with response surface methodology was adopted to develop predictive mathematical models and analyze the results. The results demonstrated that an entrained air dosage of 3.5% could improve the UCS of the mine backfill owing to better dispersion of cement particles. However, a further increase in the dosage reduced the UCS as well as the fresh and dry densities by approximately 200 and 120 kg/m³, respectively. Study results imply that using air-entraining admixtures can potentially enhance mine backfill flowability and reduce the density, thus providing safer and more sustainable working conditions in an underground mining environment.

中文翻译：

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夹带空气对水泥矿回填特性的影响：基于响应面法的分析

作为探讨在矿井回填中使用引气剂的潜在益处的一项广泛研究计划的一部分，本文提供的实验研究调查了水泥和引气量对矿井回填无侧限抗压强度（UCS），新鲜密度，和干密度。回填样品使用硅砂，普通硅酸盐水泥，水和夹带的空气混合物制备。采用响应面方法进行实验设计，建立预测数学模型并分析结果。结果表明，由于水泥颗粒的分散性更好，引气量为3.5％可以改善矿井回填的UCS。但是，剂量的进一步增加使UCS以及新鲜和干密度降低了约200和120 kg / m³，分别。研究结果表明，使用引气剂可以潜在地提高矿井回填的流动性并降低密度，从而在地下采矿环境中提供更安全，更可持续的工作条件。