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What is Block Caving and How is it Implemented?

Introduction to Block Caving

• Block caving, or "hundimiento de bloque," is a mining method that utilizes controlled fracturing of rock, leveraging gravity to extract material.

• In the PMCHS (Presumably a mining site), this process involves exploitation units consisting of two macrobloques, each covering approximately 35,000 m².

• The height for the first level of exploitation ranges from 200 to 400 meters, depending on the depth of the pit.

Infrastructure Development in Mining

• Initial construction included permanent works such as bidirectional access tunnels, main transport tunnels, air injection tunnels, and an air extraction shaft.

• Following these developments was the construction of the BIS (Barrio Industrial Subterráneo), located adjacent to the first level of mine exploitation.

Preconditioning Units for Exploitation

• Preconditioning involves creating three vertical descending drill holes that reach down to each macrobloque's sinking level.

• High-pressure pumps inject water into these holes to create controlled fractures in order to weaken the rock mass; this technique is known as hydrofracturing.

Finalizing Preconditioning and Production Preparation

• The preconditioning stage concludes with confined blasting or dynamic weakening using explosives.

• After preconditioning, preparation for mineral extraction begins at the production level by blasting the base of blocks and facilitating gravitational flow as minerals are extracted.

• Extraction occurs symmetrically and alternately from the center towards both sides within each macrobloque.