Geoscience Reference
In-Depth Information
12
Data points from Suzuki et al (1998) for
(N)
78
5; [(N)
60
5]
£
£ 6.
5
£
(N)
78
< 10; [6.5
£
(N)
60
< 13]
10
10
£
(N)
78
< 20; [13
£
(N)
60
< 26]
Approximate trend for :
8
Average (N)
60
≈
20
Average (N)
60
≈
10
6
Average (N)
60
≈
4
4
2
0
0
20
40
60
80
100
Fines Content, FC (%)
)
60
as afunction of fines content
(data points from Suzuki et al., 1998 adjusted by a factor of 78/60 to account for energy
delivered toSPT sampler)
Fig. 1.11. Variations of the ratioq
cN
/(
N
varied systematically with fines content and D
R
(or N). This is illustrated in Figure 1.11
showing their data in terms of q
cN
/(
N
)
60
versus fines content, FC, for three ranges of
(
)
60
values. Their SPT blow count data most likely corresponded to an energy ratio
of about 78%, and hence were adjusted to an equivalent energy ratio of 60% to obtain
the
N
)
60
values presented in Figure 1.11. The three sets of data points presented in
Figure1.11arefor
(
N
(
N
)
60
<
6
.
5(average
≈
4),for
(
N
)
60
rangingfrom6.5to13(average
≈
(
)
60
ranging from13 to26(average
≈
10), and for
N
20).
(
)
60
<
.
The data points for
5 covered a sufficient range of fines contents to enable
construction of a reasonable relationship between q
cN
/(
N
6
N
)
60
and fines content for an
average
)
60
of4. AlsoshowninFigure 1.11arerelationships thatwerederived forthe
other two ranges of
(
N
(
N
)
60
and which follow the form derived for
(
N
)
60
=
4. These three
relationships were used, with interpolation, to estimate q
cN
/(
N
)
60
ratios for different
values of
)
60
and fines content.
Fines content adjustments,
(
N
q
c1N
-
Sr
, for CPT penetration resistances were derived to
be consistent with those adopted for the SPT-based approach. The resulting values for
q
c1N
-
Sr
arelistedinTable 1.3.
CPT penetration resistances were estimated for each of the case histories listed in
Table1.1asfollows.Valuesofq
c1N
wereestimatedbymultiplyingtheSPT
(
N
1
)
60
values
