Predicting displacements of ore body boundaries in generation of blasted rock pile

The review of the present-day studies into blasting-induced displacement of ore boundaries reveals two current approaches to the boundary displacement determination: the direct measurement of the displaced boundary using special tools placed in rocks and the predictive modeling of displacement. The advantages and disadvantages of the approaches are described. The conclusion is draw that any prediction of the ore body boundary displacement is either difficult and time-consuming, or is unverified practically. This article presents a simplified calculation algorithm for ore boundary displacements in variation of basic blasting pattern designs. Pilot blasting was carried out to trial the proposed analytical model. The calculations show that the ore body boundary displaces from its initial position by 5–7 m, while the direct measurement by sampling of blasted rock pile points at the displacement of the test boundary by 6 m. The calculation and measurement agreement is 80%, which is permissible in the test problem. The general provisions are given to select a predictive model of ore body boundary displacement for specific mining and blasting conditions.

Khokhlov S. V., Vinogradov Yu. I., Noskov A. P., Bazhenova A. V. Predicting displacements of ore body boundaries in generation of blasted rock pile. MIAB. Mining Inf. Anal. Bull. 2023;(3):40-56. [In Russ]. DOI: 10.25018/0236_1493_2023_3_0_40.

S.V. Khokhlov¹, Cand. Sci. (Eng.), Assistant Professor, e-mail: khokhlov_sv@pers.spmi.ru, ORCID ID: 0000-0003-1040-8328,
Yu.I. Vinogradov¹, Cand. Sci. (Eng.), Assistant Professor, e-mail: vinogradov_yui@pers.spmi.ru, ORCID ID: 0000-0001-9468-2214,
A.P. Noskov, Managing Director, Polyus Aldan JSC, Nizhny Kuranakh, 678940, Russia, e-mail: NoskovAP@polyus.com,
A.V. Bazhenova¹, Graduate Student, e-mail: s195054@stud.spmi.ru, ORCID ID: 0000-0002-8155-2258,
¹ Saint-Petersburg Mining University, 199106, Saint-Petersburg, Russia.

S.V. Khokhlov, e-mail: khokhlov_sv@pers.spmi.ru.

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