Block caving mining method - Epiroc

Block Caving: An Overview

Introduction to Block Caving

• Block caving is a large-scale mining method designed for efficient extraction of substantial rock volumes.

• The development time before production initiation is longer compared to other mining methods.

Mechanism of Block Caving

• The process involves creating a gap by drawing rock from the lower extraction level, leading to the overlying rock mass caving due to gravity and stress.

• This technique minimizes drilling and blasting but requires favorable conditions such as a sufficiently large ore body for natural breakage.

Preparation for Extraction

• To initiate the caving process, an undercut level must be developed and blasted below the extraction level.

• Draw bells are established between undercut and extraction levels, serving as passages for the caved rock.

Safety Measures in Block Caving

• Accurate drilling is essential to avoid misfires during blasting operations.

• Rock reinforcement techniques include using steel arches, sprayed concrete, cable bolts, rock bolts, steel mesh, and straps due to extreme rock stress changes throughout the long production period.

Transportation of Extracted Ore

• Once extracted from draw points, rock can be transported via various methods either into haulage levels or directly into crushers.