Return on experience from full-scale open pit blasting experiments

Keyword(s):  
2021 ◽  
pp. 58-62
Author(s):  
I. F. Bondarenko ◽  
R. Ya. Nikitin ◽  
I. V. Zyryanov

ALROSA performs blasting operations mainly using explosives manufactured on the spot. Considering modern trends of using local manufacture explosives, Company’s experience of application of emulsion explosives, as well as prompt introduction of technological innovations, novel process solutions are utilized in manufacture and use of emulsion explosives. To this effect, Udachny Mining and Processing Plant constructed and commissioned a plant to manufacture non-explosive components for emulsion explosives within the Plant’s infrastructure area. Emulsion explosives enable blasting in open pit and underground mines which are assumed hazardous in terms of oil and gas shows. Within the framework of technical upgrading at MMLT-500-PR Plant, the investment project on construction and commissioning of a modular production line to manufacture packaged emulsion explosives has been implemented. The field trials of NPGM grade emulsion explosive has proved the economic and production efficiency of blasting using this explosive in open pit and underground mining. This article presents the results of testing and application of NPGM emulsion explosive during blasting in open pit and underground mines of ALROSA. The outcomes of pilot explosions using this type explosive as the main borehole and chain charges, as well as intermediate detonators in full-scale conditions of an underground mine and in an open pit are described. The proposed technology features higher operational efficiency and is applicable in various geotechnical conditions of mineral mining.


Author(s):  
Andreas Svanberg ◽  
Simon Larsson ◽  
Rikard Mäki ◽  
Pär Jonsén

Abstract Rope shovels and other heavy mining equipment used for loading fragmented rocks to extract minerals from the earth are used in almost every open pit mine. The optimization of the loading process is of enormous value due to the extremely large amount of material turn over. In this work, a full-scale numerical model of the loading process is developed. Granular material of copper ore is modeled in a combination of rigid finite elements for larger particles with complex shapes, and the discrete element method for smaller particles. A multi rigid body dynamic model, discretized with finite elements are used to model the rope shovel. Calibration of the numerical model for the granular material is performed via a new and unique experimental full-scale approach of analyzing waste rock pile angles with a height of approximately 15 m. In situ experimental data acquisition is performed during the loading process for validation of the model. After model validation, the influence of several loading variables such as bucket rake angle, velocity, and position from the pile are investigated and evaluated. When comparing the numerical model results with experimental mass measurement an excellent agreement was observed. Also, drone camera video recordings of the mass flow behavior and the numerical mass flow behavior are in agreement. Small adjustments of dig variables show a significant effect on the average dig force as well as the bucket fill factor.


2015 ◽  
pp. 15-20 ◽  
Author(s):  
G. V. Shubin ◽  
◽  
B. N. Zarovnyaev ◽  
I. F. Bondarenko ◽  
A. S. Kurilko ◽  
...  
Keyword(s):  

2000 ◽  
Vol 16 (2) ◽  
pp. 107-114 ◽  
Author(s):  
Louis M. Hsu ◽  
Judy Hayman ◽  
Judith Koch ◽  
Debbie Mandell

Summary: In the United States' normative population for the WAIS-R, differences (Ds) between persons' verbal and performance IQs (VIQs and PIQs) tend to increase with an increase in full scale IQs (FSIQs). This suggests that norm-referenced interpretations of Ds should take FSIQs into account. Two new graphs are presented to facilitate this type of interpretation. One of these graphs estimates the mean of absolute values of D (called typical D) at each FSIQ level of the US normative population. The other graph estimates the absolute value of D that is exceeded only 5% of the time (called abnormal D) at each FSIQ level of this population. A graph for the identification of conventional “statistically significant Ds” (also called “reliable Ds”) is also presented. A reliable D is defined in the context of classical true score theory as an absolute D that is unlikely (p < .05) to be exceeded by a person whose true VIQ and PIQ are equal. As conventionally defined reliable Ds do not depend on the FSIQ. The graphs of typical and abnormal Ds are based on quadratic models of the relation of sizes of Ds to FSIQs. These models are generalizations of models described in Hsu (1996) . The new graphical method of identifying Abnormal Ds is compared to the conventional Payne-Jones method of identifying these Ds. Implications of the three juxtaposed graphs for the interpretation of VIQ-PIQ differences are discussed.


1996 ◽  
Vol 12 (1) ◽  
pp. 27-32 ◽  
Author(s):  
Louis M. Hsu

The difference (D) between a person's Verbal IQ (VIQ) and Performance IQ (PIQ) has for some time been considered clinically meaningful ( Kaufman, 1976 , 1979 ; Matarazzo, 1990 , 1991 ; Matarazzo & Herman, 1985 ; Sattler, 1982 ; Wechsler, 1984 ). Particularly useful is information about the degree to which a difference (D) between scores is “abnormal” (i.e., deviant in a standardization group) as opposed to simply “reliable” (i.e., indicative of a true score difference) ( Mittenberg, Thompson, & Schwartz, 1991 ; Silverstein, 1981 ; Payne & Jones, 1957 ). Payne and Jones (1957) proposed a formula to identify “abnormal” differences, which has been used extensively in the literature, and which has generally yielded good approximations to empirically determined “abnormal” differences ( Silverstein, 1985 ; Matarazzo & Herman, 1985 ). However applications of this formula have not taken into account the dependence (demonstrated by Kaufman, 1976 , 1979 , and Matarazzo & Herman, 1985 ) of Ds on Full Scale IQs (FSIQs). This has led to overestimation of “abnormality” of Ds of high FSIQ children, and underestimation of “abnormality” of Ds of low FSIQ children. This article presents a formula for identification of abnormal WISC-R Ds, which overcomes these problems, by explicitly taking into account the dependence of Ds on FSIQs.


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