用灰关联分析方法确定影响岩体爆破质量的主要因素

用灰关联分析方法确定影响岩体爆破质量的主要因素。在简介灰关联分析原理及其计算方法后,通过实例计算与分析,得到各影响因素的主次关系。并且发现:节理裂隙岩体中的爆破块度指标主要受爆区内节理裂隙分布特征的控制;其次,也与均质岩体中的爆破一样,影响块度分布的主要因素是炮孔间距、排距和最小抵抗线等。

DETERMINATION OF PRINCIPAL FACTORS AFFECTING THE QUALITY OF ROCK BLASTING WITH GREY CORRELATION ANALYSIS

Rock blasting is considered as a grey system and the principal factors affecting the quality of rock blasting are detdermined by the grey correlation analysis in this paper. The fundamentals of the grey correlation analysis and its calculating method are briefly introduced. Taking four field blasting results as examples, the authors calculated their grey absolute correlation grades respectively and obtain the corresponding grey absolute correlation matrixes. Through calculations and analyses, the authors come to the main conclusion as following:1. The grey correlation analysis may determine the relationship between the primary and the secondary of all the factors affecting the blasting quality in different mines and blasting conditions. It supplies a simple and useful method in selecting parameters to controll and predict the blasting quality.2. For multiple blasting quality indexes, usually, two or more factors control the blasting quality. But for a single index, it is necessary that there is a factor which dominantly affects the blasting quality.3. The size indexes of fragments resulting from rock masses blasting are mainly influenced by the distribution of the joints and cracks within rock masses. The space of joints and cracks affects the average and characteristic size of fragments, the length of joints and cracks determines the amounts of big fragments.4. Among all the blast parameters, the hole space and row space as well as the burden play a leading role in the size distribution of fragments. When joints and cracks are not developed within blasting regions, the optimum blasting and the control of fragment size will be realised by adjusting these parameters reasonably.5. Under different charcteristics of rock masses and blasting forms, the same blast parameter plays a different role in the size ditribution of fragments.