Page 8 - Technical E-Booklet Stone Column (Group 3)

H O W D O E S
When a vibro flotation machine (stone column

equipment) is driven into the loose ground, it creates a

hole. Gravel particles of a certain size are then fed into
S T O N E
the hole, either using the top feed or bottom feed

method. The top-feed method is used when a stable

hole can be formed by the vibratory probe. With the dry
C O L U M N
method (top or bottom-feed), the probe is inserted into

the ground and penetrates to the

target depth under its own weight and compressed air

C O N S T R U C T ?
jetting

( T A U B E A N D H E R R I D G E , 2 0 0 2 )
BOTTOM FEED METHOD FOR STONE

COLUMN PROCEDURE.

STEP V I B R O C A T S T A B I L I S E D

O N H Y D R A U L I C S
1

O U T R I G G E R S

T h e l e a d e r s a r e e l e v a t e d t o t h e v e r t i c a l

a n d t h e v i b r a t o r l o c a t e d o n t h e g r o u n d

a t t h e s t o n e c o l u m n p o s i t i o n . T h e s k i p

i s c h a r g e d w i t h s t o n e .

STEP S K I P T R A V E L S U P T H E

2 L E A D E R S

A u t o m a t i c a l l y d i s c h a r g e s s t o n e i n t o t h e

r e c e p t i o n c h a m b e r a t t h e t o p o f t h e

v i b r a t o r

STEP V I B R A T O R P E N E T R A T E S

3

V i b r a t o r p e n e t r a t e s t h e w e a k s o i l s t o

t h e d e s i g n d e p t h u n d e r t h e a c t i o n o f

t h e v i b r a t i o n s , c o m p r e s s e d a i r a n d p u l l -

d o w n w i n c h f a c i l i t y

STEP R E Q U I R E D D E P T H

4

S t o n e i s r e l e a s e d a n d c o m p a c t e d b y

s m a l l u p w a r d a n d d o w n w a r d

m o v e m e n t s o f t h e v i b r a t o r , t h e p u l l -

d o w n b e i n g e m p l o y e d o n t h e

d o w n w a r d c o m p a c t i n g a c t i o n

STEP ADDED STONE

5 Stone being added to the system as

necessary at any stage of the construction

procedure, a stone column of very high

integrity, tightly interlocked with the

surrounding soil, is built up to ground

level