671017.pdf

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changing pattern of horizontal permeability coefficient versus
푟.Thesolutionsof퐹푐hadbeengivenbyZhangetal.[ 24 ]as


퐹푐=

푛^2

푛^2 −1

{

푠−1

휅푠 − 1

ln(휅푠)−

(푠−1)^2

푛^2 (1−휅)

+

2

푛^2

(푠−1)(휅푠 − 1)

(1−휅)^2

ln

1



2

푛^4

푠−1

1−휅

×(

푠^3 −1

3


푠^2 −1

3

)−

1

푛^4

(푠−1)(휅푠 − 1)

(1−휅)^2

×[

푠^2 −1

2


(푠−1)(휅푠 − 1)

1−휅

+

(휅푠 − 1)^2

(1−휅)^2

ln

1


]


푛^2 −푠^2

푛^4

(1−푠)^2

1−휅

+ln




3

4

+

4푛^2 푠^2 −푠^4

4푛^4

}.

(29)

3. Parametric Study and Discussion

In order to study the characters of consolidation of CCSG pile
composite foundation,훽푚should be converted to dimension-
less, which can be expressed as


훽푚푡=휏푚푇ℎ, (30)

where푇ℎis the horizontal time factor of the soil, which can
be expressed as


푇ℎ=

푐ℎ푡

4푟^2 푒

,푐ℎ=

퐸푘ℎ

훾푤

. (31)

In this case, ( 25 )changesinto

푈=1−



푚=1

2

푀^2

푒−휏푚푇ℎ, (32)

where


휏푚=푟^2 푒(훼 + 푛^2 −1+푌)

×{

푘V푤

푘ℎ

(



)

2
[

푟^2 푒퐹푐

2

+

(푛^2 −1)푅푘ℎ

(1 − 푎^2 )8푘ℎ푤

]

+(푛^2 −1)+

푘V푤

푘V

}




  1. 2

  2. 4

  3. 6

  4. 8

  5. 0
    0.0001 0.001 0.01 0. 1110


n=4
n=6

n=8
n=10

Th

U

Figure 4: Influence of푛on consolidation process.




  1. 2

  2. 4

  3. 6

  4. 8

  5. 0
    0.0001 0.001 0.01 0. 1110


H/dw=20
H/dw=50
H/dw= 100

Th

U

Figure 5: Influence of퐻/푑푤on consolidation process.

×(

{

{

{

(푛^2 −푎^2 )

2

1−푎^2


푘ℎ

푘V

(



)

2

+[(푛^2 −1)

푘V푤

푘V

+1]

⋅(

푟^2 푒퐹푐

2

+

푅(푛^2 −1)푘ℎ

8푘ℎ푤

)

}

}

}

)

−1

.

(33)

From the expression of휏푚, the dimensionless parameters
influencing the consolidation character of CCSG pile com-
posite foundation include푛,푎,푠,푋,푌,퐻/푑푤(푑푤 =2푟푤),
푘ℎ/푘V,푘푠/푘ℎ,푘ℎ/푘V푤,푘ℎ/푘ℎ푤,and푘ℎ푤/푘V푤.Theinfluences
of several dimensionless parameters on the consolidation
behaviourofCCSGpilecompositefoundationwereinves-
tigated and some numerical results from different solutions
were compared according to the above formula. The specific
calculation results are shown in Figures 4 – 11 .Thecalculating
parameters are shown inTa b l e 1.
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