Stress Measurements to Confirm Stress Field Components for FOG Prevention in Complex Geological Areas
COALTECH Project Number: CSIR/MIN/MTS/RPO/2025/0001/A
By JWL Hanekom, K Mphahlele – CSIR
C Smith – Groundwork Consulting
T Morakile – SRK Consulting
C Skinner, R Gonsalves – Seriti Coal | May 2026
R1500,00
Description
The project assessed whether the DCDA method could provide a practical, lower-cost approach for estimating underground stress conditions in South African coal mines.
Testing at Kriel Colliery confirmed that both CCBO and DCDA methods can be applied, although results are strongly affected by drilling quality, core damage, anisotropy and rock mass conditions.
CCBO produced meaningful underground stress data, while DCDA showed promise in detecting stress-related deformation, particularly in coal samples.
The strongest potential for DCDA appears to be in identifying stress orientation changes rather than reliably determining stress magnitudes at this stage.
Further development is recommended, including improved drilling controls, better core orientation procedures and additional testing across different geological environments.
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