Summary: | 碩士 === 國立臺灣科技大學 === 營建工程技術學系 === 81 === A 2-D laboratory model test and a full scale field test were
adopted to study the deformation characteristics of soil around
the grout bulb generated by the compaction grouting method. It
was found that if the soil was not homogeneously deposited, the
grout bulb tended to develop first toward the soil with lower
strength before a more homogeneous soil mass has been achieved.
This phenomenon was confirmed by the field test. The degree of
strength improvement of the soil tended to decrease with the
dis- tance from the injection point. The weaker the original
shear strength, the higher the degree of strength impro- vement
can be obtained. However, the UUU triaxial test results also
indicated that the area of influence did not increase
unlimitedly with the volume of grout being injected into the
soil. No obvious increase in the grout bulb in- fluenced area
was observed when the radius of the influenced area was more
than three times as large as that of the grout bulb. However,
the degree of strength improvement for the soil within the
influenced area was found to increase with the volume of
injected grout. Field test results showed that the SPT blow
counts for the soil in between the neighboring injecting points
could be increased as much as 150~200% if the infecting points
were properly layouted and certain the water pressure
dissipation pipes were installed.
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