散体云母片岩击实破碎特性试验研究

EXPERIMENTAL STUDY ON COMPACTION AND FRAGMENTATION CHARACTERISTICS OF LOOSE MICASCHIST

以某露天矿散体云母片岩为研究对象,对散体岩石物料开展不同级配和含水率条件下的击实试验,分析散体物料的击实特性,以及最大干密度、最优含水率和孔隙比随粗颗粒含量的变化关系;在此基础上,引入Bg颗粒破碎指标,探讨击实过程中散体颗粒的破碎特性。研究表明:1)随粗颗粒含量的增加,散体云母片岩的最大干密度呈现先增大后减少的非线性变化关系,最优含水率和孔隙比则相反;2)当粗颗粒含量为60%～70%时,最大干密度值出现峰值,且试样含水率和孔隙比最小,说明该级配条件下散体物料压实度最好;3)当粗颗粒含量在10%及其以下时,在相同击实功作用下颗粒将不再发生破碎,与此同时,破碎率也不会随着含水率的改变而发生变化;4)粗颗粒含量和含水率是影响颗粒破碎率的两个重要因素,但相对于含水率而言,粗颗粒含量对破碎率的影响要更加显著。

Taking loose micaschist of strip-mine as study object, compaction tests on loose rock materials are carried out under different gradation and water content conditions to analyze the compaction properties of loose rock materials and the relationships of the coarse particle content with the maximum dry densities, optimum water content and void ratio. On this basis, Bg as particle breakage index is applied to discuss the fragmentation characteristic of loose particle in the process of compaction. The research shows that： 1） the maximum dry densities of loose micaschist increases first and then decreases with the increase of coarse particle content, and the optimum water content and void ratio are the opposite; 2） peak-value of the maximum dry densities appears when the coarse particle content of loose micaschist is 60% -70% , and the water content and void ratio of sample are minimum, which show that the loose rock materials have the best compaction in this distribution; 3） there would be no fragmentation behaviors under the same compaction when the coarse particle content of loose micaschist is less than 10% , meanwhile the breakage index does not change with the moisture content; d） the coarse particle content and water content are two key factors to affect the particle breakage index, among which, the effect of coarse particle content is more significant than water content.