Powder factor analysis of quarry blasts through the fragmentation-energy fan concept
| Autor: | Sanchidrián Blanco, José Angel, Segarra Catasus, Pablo, Navarro Miguel, Juan, Castedo Ruiz, Ricardo |
|---|---|
| Rok vydání: | 2019 |
| Předmět: | |
| Zdroj: | Proceedings of the 45th Annual Conference on Explosives and Blasting Technique | 45th Annual Conference on Explosives and Blasting Technique | 27-30 enero 2019 | Nashville, TN, USA Archivo Digital UPM instname |
| Popis: | This paper investigates fragmentation in an aggregate quarry in the light of the fragmentation-energy fan concept. Six blasts were monitored, located one behind the other in the same quarry area. The rock structure was blocky, the water level and the usage of explosives were variable within and between the blasts. The powder factor above grade was between 0.28 and 0.44 kg/m3. Fragmentation of the plant feed was measured using an online digital image analysis system and three belt scales. The oversize material that was not directly fed to the plant after the blast corresponds to 3‒9.3 % of the total. Data from image analysis was used to build the size distribution in the coarse range (fragments above 120 mm), and the passing fractions at 120 and 25 mm obtained from belt scales data were used in the range 120‒25 mm. The non-dimensional percentile sizes between 10 and 90 % for each blast are described through power functions of the powder factor above grade; the model coefficients are statistically significant. From them, using the principles of the fragmentation-energy fan and the Swebrec distribution properties, the fragmentation can be expressed in terms of the powder factor by means of five parameters: the fan focus coordinates and the three parameters of a function of the exponents vs. the percentage passing. The model shows a good capability to describe fragmentation. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|