Sustainable Ground Improvement Technique for Geo-Disaster Mitigation - Sustainable Practices in Geoenvironmental Engineering - page 458

300

Prediction based on
Equation 12.17

200

q

100

Triaxial compression

0

0 100 200 300 400 500

p'

FIGURE 12.13
Relationships between p ′ and q for actual triaxial compression and prediction. Units for both axes are in kPa.

the center and radius of the largest Mohr's circle in Figure 12.12b, respectively. This p ′ -q
relationship is a tool that can be used for design of soil improvement.

12.6.2.3 Cone Penetration Resistance

Figure 12.14 shows the change in cone penetration resistance ( N sw ) as a result of microbial
cementation (carbonate content about 0.5% at a soil depth of 60 cm) of loose medium sand.
Figure 12.14 shows that penetration resistance increases because of carbonate cementa-
tion—i.e., the number of blows, N sw —increases from approximately 10 to 70 at a soil depth
of 60 cm, and as one would expect, the number of resistance blows depends on the carbon-
ate content.

Number of blows ( N sw )

0 5 10 15 20 25 30

0

20

After precipitation

40

60

80

100

120

Before

140

160

FIGURE 12.14
Results of the dynamic cone penetration test for sand with and without microbial cementation.