94 Ground improvement by deep vibratory methods
with a total dead load of 2200 kN consisting of concrete blocks. The load
was applied in equal increments of 25% of the design footing pressure of
250 kPa up to a maximum load equal to 500 kPa. Figure 3.45 gives the pressure versus settlement curve for one of the load tests, and Table 3.11 shows
the recorded settlements at design and twice design bearing pressure for all
three load tests.
The relatively high stiffness as derived from the load tests indicates a
better compaction than expected. When using a constrained modulus of
145 MN/m 2 , which was measured in load test 1, for a settlement calculation, the tank centers will settle less than 20 mm, which compares favorably with the finite element analysis mentioned above in which the stiffness
employed was derived from a correlation with post-CPT tip resistances.
9
8
7
6
5
4
3
2
1
0
0
1
2
3
4
5
6
60
50
40
30
20
10
0
Depth (m)
Cone resistance q c (MPa)
Friction ratio R f (%)
Figure 3.44 Posttreatment cone penetration tests (each curve representing the average
of 21 CPTs) and CPT target line.