Coaltech Research Association

Development of Seam-Specific Strength Formulae for South African Collieries

Statistical back analysis of an expanded collapse database, testing power, linear and non-linear strength models, for rock engineers setting pillar safety factors.

by M.D.G. Salamon, I. Canbulat and J.A. Ryder | January 2006

What this report found

Back analysis of 77 collapsed and 245 uncollapsed pillar cases showed that much of the scatter in pillar strength comes from differences between coalfields, so a single national formula is unrealistic. Seam specific formulae were derived for the major coalfields; Free State and KwaZulu Natal data remained too sparse. The lognormal safety factor distribution was retained.

R1500,00

Description

Related Products

J van Brakel

Benefits of an Apiary at a Rehabilitation Site

Ian Mey

2019

Desktop study based on literature, a stakeholder workshop and specialist consultation, assessing whether keeping bees on rehabilitating mine land pays, for closure teams weighing aftercare options.

What this report foundThe financial benefit of bees to a rehabilitating site could not be modelled with confidence, and a field trial to show direct benefit is hard to configure...

R1500,00

R1500,00

Ian Mey

What this report found

The financial benefit of bees to a rehabilitating site could not be modelled with confidence, and a field trial to show direct benefit is hard to configure because so many variables affect rehabilitation. Apiaries suit sites where bee friendly plants are established, the return coming through honey yield rather than measured gains in biodiversity or ground cover, at low establishment cost.

SJ Mangena

Coal Washability Using Coal Petrography

2019

Summary of postgraduate work validating washability prediction for southern African coals by image analysis and tomography, written for geologists, metallurgists and mining engineers valuing a deposit.

What this report foundA single float sink test destroys the sample and gives one deterministic answer, so it cannot show how washability changes with particle size distribution.

R1500,00

R1500,00

What this report found

A single float sink test destroys the sample and gives one deterministic answer, so it cannot show how washability changes with particle size distribution. Simulating washability from petrographic images and tomography allows many size distributions to be tested statistically from one sample. Running simulation alongside float sink work during exploration lets the prediction error of each be compared.

Shopping Basket