11.2 Semi-empirical Approach
159
Now that the relations have been discussed and somewhat framed in reality,
Table 11.4 is the key to determine the category of a structure based on a number
of its characteristics. To display it in this book, we have adapted it from the original
versions of SLM and (Altarejos et al. 2015). The original papers give detailed explanations on how to determine the category of a structure and suggests interpolation
techniques to cover intermediate cases. That is necessary because a structure has
generally varying degrees of quality over the various areas of characterization. In
our dam-specific version we look at thirty diagnostic points, including design, construction, liquefaction potential, internal erosion potential, management, monitoring
and maintenance as well as other specific dam-related points, and adopt a min-max
approach to define a range of probabilities of failure to avoid conveying a sense of
false “accuracy”. As Fig. 10.5 makes clear, the level of uncertainty can vary quite
considerably from dam to dam.
Table 11.4 How to determine a geo-structure category
Category
Design
Build
Operate
D1
D2
D3
CO
OM
Investigation Testing
Analyses and
documentation
Construction Operations
and
monitoring
I Best
Evaluate
design and
performance
of nearby
structures
Run lab tests
on
undisturbed
specimen at
field
conditions
Determine
FS using
effective
stress
parameters
based on
measured
data for site
Full time
supervision
by qualified
engineer
Complete
performance
program
including
comparisons
between
predicted and
measured
Analyze
historic
aerial photos
Run strength
tests along
field
effective
total and
effective
stress paths
Consider
field stress
path in
stability
determination
Construction
control tests
by qualified
engineers
and
technicians
no
malfunctions
(cracks
slides etc.)
Locate all
non
uniformities
Run index
field tests
(field vane,
come penetrometer) to
detect
anomalies
Prepare flow
nets for
instrumented
sections
No errors or
omissions
Continuous
maintenance
(continued)
159
Now that the relations have been discussed and somewhat framed in reality,
Table 11.4 is the key to determine the category of a structure based on a number
of its characteristics. To display it in this book, we have adapted it from the original
versions of SLM and (Altarejos et al. 2015). The original papers give detailed explanations on how to determine the category of a structure and suggests interpolation
techniques to cover intermediate cases. That is necessary because a structure has
generally varying degrees of quality over the various areas of characterization. In
our dam-specific version we look at thirty diagnostic points, including design, construction, liquefaction potential, internal erosion potential, management, monitoring
and maintenance as well as other specific dam-related points, and adopt a min-max
approach to define a range of probabilities of failure to avoid conveying a sense of
false “accuracy”. As Fig. 10.5 makes clear, the level of uncertainty can vary quite
considerably from dam to dam.
Table 11.4 How to determine a geo-structure category
Category
Design
Build
Operate
D1
D2
D3
CO
OM
Investigation Testing
Analyses and
documentation
Construction Operations
and
monitoring
I Best
Evaluate
design and
performance
of nearby
structures
Run lab tests
on
undisturbed
specimen at
field
conditions
Determine
FS using
effective
stress
parameters
based on
measured
data for site
Full time
supervision
by qualified
engineer
Complete
performance
program
including
comparisons
between
predicted and
measured
Analyze
historic
aerial photos
Run strength
tests along
field
effective
total and
effective
stress paths
Consider
field stress
path in
stability
determination
Construction
control tests
by qualified
engineers
and
technicians
no
malfunctions
(cracks
slides etc.)
Locate all
non
uniformities
Run index
field tests
(field vane,
come penetrometer) to
detect
anomalies
Prepare flow
nets for
instrumented
sections
No errors or
omissions
Continuous
maintenance
(continued)