废石干式充填压实力学特征及影响因素研究

为改善废石干式充填效果，提高充填强度，采用物理试验和理论计算等方法研究废石干式充填的压实力学特征及其影响因素。结果表明：试样的粒径级配以及级配的连续性对试样的密实度影响较大，连续性级配的密实度较低，试样抗压能力更强。通过极差分析，级配系数n对轴向应变的影响大于最大粒径D;试样轴向应变-应力曲线表明，试样宏观变形的主要来源是对孔隙的直接压缩和填充。变形模量-轴向应力曲线表明，废石试样粒径分布完善，且各范围粒径之间应有一个合理的比例关系，使得试样通过发生较少的轴向应变达到稳定状态。试样分形特征表明，合理的级配系数n以及最大粒径D可以提高废石颗粒的破碎程度，并提高试样的抗压能力。确定了废石最佳粒径级配为n=0.4、D=30 mm。研究结果对废石干式充填具有一定指导意义。

Mechanical characteristics and influencing factors of dry filling compaction of waste rock

In order to improve the effect of dry filling of waste rock and improve the filling strength, this paper studies the compaction mechanical characteristics and influencing factors of dry filling of waste rock utilizing physical tests and theoretical calculations. The results show that the particle size gradation of the sample and the continuity of the gradation have a great influence on the compactness of the sample. The compactness of the continuous gradation is lower and the compressive strength of the sample is stronger. Through range analysis, the influence of gradation coefficient n on axial strain is greater than that of maximum particle size D ; the axial strain-stress curve of the specimen shows that the main source of the macroscopic deformation of the specimen is the direct compression and filling of the pores. The deformation modulus-axial stress curve shows that the particle size distribution of the waste rock sample is perfect, and there should be a reasonable proportional relationship between the particle sizes in each range so that the sample reaches a stable state through less axial strain. The fractal characteristics of the sample show that the reasonable Taibo coefficient n and the maximum particle size D can improve the crushing degree of the waste rock particles and improve the compressive strength of the sample. The optimum particle size gradation of waste rock was determined: n = 0.4, D = 30 mm. The research results have a certain guiding significance for the dry filling of waste rock.