Lecture2_site investigation.pdf

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SITES INVESTIGATION AND INSITES INVESTIGATION AND IN--SITU TESTINGSITU TESTING

111/7/2011 Dr.Jirayut Suebsuk 211/7/2011 Dr.Jirayut Suebsuk

311/7/2011

Water content, Atterberg limits

c , ,

u

Cc,Cr,OCR

411/7/2011 Dr.Jirayut Suebsuk


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1.

2.

3.

4.




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(budget)

(soil variability)

20-40

10

11/7/2011

50 30 15 4

60 30 15 3

30 7 1-2

300 150 30

- - -

( af t er Sower, 1979)


()

0.7

6 ()0.7



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r a

,

undisturbed block

14



(Undisturbed Clay Samples)

(triaxial test) conso a on es

A

R< 10%

2 2

2

outer inner

RA

=

..

inner



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ranu ar so

in-situ

tests) (penetation test)

80-90%


an ugers (Wash boring)

(PercussionDrilling)

(Rotary Drilling)


as or ng


ercuss on r ng



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o ary r ng


(Disturbed samples)

, p t spoon

, ,

Basic properties Engineering properties

22

11/7/2011

(Undisturbed sample)

(Thin-walled tube) ston samp er ,

Engineering properties


(Thin Wall Tube)

Drill rod

Drilling rod

Thin wall tube

Thin wall tube



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(Piston Sampler)


n-s u es

1) Penetration Test

- SPT, CPT, Kunzelstab Penetration, Pocket penetrometer

2) Pnuemetric

- , ,

3) Vane shear test

4) Loading test*

- Plate load test*

- Pile load test* 2611/7/2011

2711/7/2011 Dr.Jirayut Suebsuk 2811/7/2011


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60 (Skemton, 1986)

600.60

m B RN =

Em

(Hammer efficient)CB

CR

(Drill rod)


m B RE C C NN =0.60

(E )

SPT (Clayton, 1990)

m

Donut 0.45

Pin weight 0.72

Donut 0.55

Donut 0.50

Donut 0.50

Donut (Trigger) 0.78-0.85

Donut 2 +

0.65-0.67

.

Safety 2 0.55-0.60

31

.


m B RE C C N

600.60

- - B

. . . . .

150 . (6 ) 1.05

200 . 8 1.15

(CR) 3-4 . (10-13 ) 0.75

4-6 . (13-20 ) 0.85

6-10 . (20-30 ) 0.95

> 10. (> 30 ) 1.00



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20

.5

16

on

/

2)

(ton/m2)=

N60

plastic

ity

plas

ticity

12

14

th,

Su

( u

Terzaghi and Peck (1967)layso

fmediu

lays

ofhig

10

ars

tren

ts

60

1.5u

NS =

6

ine

ds

he

wplasti

cityand

clayeys

2

4

Undra

Clays

o

2 4 6 8 10 12 14 16 18 20 22 24 26 28 300

33

an ar pene ra on num er, 60 ow11/7/2011 Dr.Jirayut Suebsuk

60NN C N=

100NC =

34


0

a)

Bazaraa (1967)

ssu

re(k

Tomlinson (1974)

200

rdenpre

300

overbu

Liao and Whitman (1986)

400ffectiv

500

35

0 1.0 2.0 3.0 4.0

Correction factor11/7/2011

N'(Peck et al., 1974)

SPT N'

(kN/m3)

(%)0-5 11-13 0-15

6-10 14-16 16-35

11-30 17-19 36-65

- - -

>50 >21 >86

!! Use with caution; unreliable.



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ynam c one ene ra on es

Simple and rugged.

Better than SPT or SCPT in hard soils such as dense gravels


a c one ene ra on es

4211/7/2011

a c one ene ra on es con .


ezocone

A modern static cone;

measures pore wa er

pressure also.



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n erpre ng ezocone a a

4511/7/2011 4611/7/2011 Dr.Jirayut Suebsuk

0

0 2 4 6 8

qc(kg/cm2)

0

0 50 100 150 200

fsc(kg/cm2)

0

0 4 8 12 16 20 24

Rf(%)

4 4 4

8

12

8

12m)

m)

8

12m)

16 16Depth(

Depth(

16Depth(

20 20 20

28 28 28

47Af t er Horpi bul suk et al .


unze s a ene ra on

Ku nzelstab Penetration9

th(m)

( )0.539 0.954KPTN N= +

( )(ksc) 0 .64 3.57 for sanda KPT q N=

Dep sc . . or c aya KPT q =

48

.



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ane ear es con .


2T M M= +s e

( ) 22v hd d

T dh S d S

= +

Torque

Undisturbed

Remoulded

(vane shear) 2 3

2 6

uS d h d

= +

( . ) (vane shear)u cor vane uS S=0 25 50 75

Rotation (Degree)

5411/7/2011

(Bjerrum, 1974)

1.2

1.0

( . ) (vane shear)u cor vane uS S=

= 1.7 - 0.54 log(PI)

.

0.6

0.4

55Plasticity Index, PI11/7/2011

e van s ear

0

0 20 40 60 80 100

0

1 2 3 4 5

SensitivityUndrained shear strength (kPa)

2

4

2

4

6

8

6

8

h(m)

12

14

12

14

Dep

16

18 UndisturbedRemolded

16

18

20 20

56 (Horpibulsuk et al., 2007)11/7/2011


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3Boring log

6111/7/2011 6211/7/2011 Dr.Jirayut Suebsuk

4

Borin lo

6311/7/2011 6411/7/2011

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Lecture2_site investigation.pdf