Seepage Modeling with SEEP/W - GeoStudio 2007 version 7.22

Chapter 2: Numerical Modeling
SEEP/W
“If we can incorporate boundary
elements rather than simple finite
elephants, enhance the statistical
evaluation of parameter generation
and stick with the fuzzy sets, I am
confident that accuracy will be
increased to at least the fourth
decimal place.”
“Put another shovel
full in Pat! It is fullcores
they’re wanting!”
Note: origins of this figure are unknown at time of printing.
2.6 How not to model
As mentioned earlier in this chapter, it is completely unrealistic to expect to set up a complex model at the
start of a project and immediately obtain realistic, understandable and meaningful results. There are far
too many parameters and issues which can influence the results, so if this is your expectation, then
modeling is going to lead to major disappointments.
For novice modelers; the initial reaction when faced with incomprehensible results is that something must
be wrong with the software. It must be a limitation of the software that the solution is inappropriate or
completely senseless. It is important to remember that the software is very powerful; it can keep track of
millions of pieces of information and do repetitive computations which are far beyond the capability of
the human mind. Without the software it would not be possible to make these types of analyses. The
software by itself is extremely powerful numerically speaking, but essentially unintelligent. Conversely,
the human mind has the capability of logic and reasoning, but has significant limitations retaining large
amounts of digital data. It is the combination of the human mind together with the capability of a
computer that makes numerical modeling so immensely powerful. Neither can do the task in isolation.
The software can only be used effectively under the careful guidance and direction of the modeler.
Sometimes it is suggested that due to a time limitation, it is not possible to start simple and then progress
slowly to a more complex analysis. A solution is needed quickly and since the budget is limited, it is
necessary to immediately start with the ultimate simulation. This approach is seldom, if ever, successful.
Usually this leads to a lot of frustration and the need to retreat to a simpler model until the solution is
understandable and then build it up again in stages. Not following the above “how to” modeling
procedures generally leads to requiring more time and financial resources than if you follow the
recommended modeling concepts.
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