Mining in focus
Tailings dams
technology:
learning from failure (Part 3)
By Adriaan Meintjes
In his third article on tailings storage facilities,
Adriaan Meintjes looks at how technology can
address the challenges.
Adriaan Meintjes, principal civil geotechnical
engineer at SRK Consulting South Africa.
About the author
Adriaan Meintjes has been involved in civil
and geotechnical engineering for over three
decades and has worked for SRK Consulting
SA since 1992. His speciality areas include
soil and rock mechanics, numerical modelling,
foundation design, water and tailings dams,
and risk assessment. Through his extensive
experience serving the mining industry, he
has developed wide-ranging expertise in the
geotechnical behaviour of tailings dams, dams,
and fills, among other fields.
Adriaan has worked on projects across
South Africa, southern Africa, and other
regions of Africa, as well as South America,
publishing and presenting over a dozen papers
at professional and scientific forums. His
qualifications were earned at Stellenbosch
University and London University, and he is a
registered professional engineer and member
of the South African Institution of Civil
Engineering (SAICE).
[20] MINING MIRROR APRIL 2019
I
n my previous two articles for Mining
Mirror on tailings storage facilities (TSFs),
I focused firstly on water security and then
on safety. This article will look more closely
at how technology has evolved with regard
to both understanding and addressing the
challenges of tailings dams. I will argue that
we are in store for exciting times, as advances
in technology promise to pave the way to
safer and more environmentally sound tailings
storage practices.
Certainly, ever-increasing computing
power — harnessed by continuously evolving
software — has allowed great strides in
the field of modelling in soil mechanics,
rock mechanics and, by extension, tailings
engineering. This will deserve more detail in a
moment. However, technology also includes
the scientific and engineering methods that
must underpin the process of discovery in
any discipline. These methods, and how they
have recently developed in regard to tailings
management, are worth some discussion
first. They form the foundation for how we
as consultants — along with our fellow-
professionals in this discipline — frame the
problems we encounter and the solutions we
recommend.
In the scientific method, we usually
investigate and quantify the laws of nature in
a theoretical or applied manner. Considering
aspects of a material’s strength, for instance,
would draw on theory such as the laws of
gravity, as well as on applied mechanics
— such as the motion of pendulums and
centrifugal forces.
The engineering method — which can
include the scientific method — usually starts
from the ‘boundaries’ of applied mechanics.
Here, there are three major approaches:
firstly, for situations where closed-form
mathematical solutions can be developed;
secondly, where reasonable mathematical
solutions can be developed; and thirdly,
where empirical methods are used to evaluate
behaviour. In geotechnical engineering, all
three approaches are followed — which is
perhaps why certain aspects of the discipline
are referred to as a science and other aspects
as an art.
Finding the answers
This leads us on to consider the value and
the role of numerical analysis in finding
answers to our questions. Numerical analyses
are based on a mathematical model which is
used to represent (in other words, to model)
some form of physical problem. To do this,
we make certain assumptions about how the
material we are looking at will behave under
different conditions.
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