chapter6 Sức bền vật liệu

Chapter 6 PILING
WORK

Construction methods and management


©2010 của Đỗ Thị Xuân Lan , GVC. Ths.

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PILING WORK
6.1. Pile types
6.2. The installing process for
displacement piles
6.3. The installing process for nondisplacement piles

©2010 của Đỗ Thị Xuân Lan , GVC. Ths.

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Chapter 6. Piling work

PILE TYPES

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Pile types

(REPLACEMENT )
NON-DISPLACEMENT

Concrete tube piles
Timber piles

Screw piles

source: Riley và Cotgrave, 2004, tr. 135

©2010 của Đỗ Thị Xuân Lan , GVC. Ths.

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Chapter 6. Piling work

THE INSTALLING PROCESS FOR
DISPLACEMENT PILES
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The installing process for
displacement piles

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Displacement piles advantages
• Material forming piles can be inspected for
quality
• Not susceptible to squeezing or necking
• The pile’s carrying capacity can be
monitored during installing process
• The construction operation is not affected
by groundwater
• Projection above groundlevel
• Can be driven to long lengths
• Can be designed to withstand high bending
and tensile stresses
©2010 của Đỗ Thị Xuân Lan , GVC. Ths.

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Displacement piles disadvantages
• May break during driving
• May suffer unseen damage which may
reduce carrying capacity

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Equipment for installing
piles
•
•
•
•
•

drop hammer
diesel hammer
hydraulic hammer
vibro-driving
jacking

source: />owtoselectofpilingrig.pdf

©2010 của Đỗ Thị Xuân Lan , GVC. Ths.

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Equipment for installing
piles
drop
hammer/
diesel
hammer/
hydraulic
hammer

jacking
vibrodriving

©2010 của Đỗ Thị Xuân Lan , GVC. Ths.

source: Riley và Cotgrave, 2004, tr. 136
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Pile driving equipment:
drop hammer

©2010 của Đỗ Thị Xuân Lan , GVC. Ths. source: />

Pile driving equipment:
drop hammer
• A drop hammer normally can deliver 4-8
blows/minute → For driving piles on
remote projects that require only a few
piles
• Small investment, simplicity of
operation, ability to vary energy per blow
• Slow rate of driving piles, danger of
damaging piles or adjacent buildings,
unable to use directly for underwater
driving
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Pile driving equipment:
diesel hammer

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Pile driving equipment:
diesel hammer

source:
/>%E1%BA%ADp_tin:DSCF0017.jpg

©2010 của Đỗ Thị Xuân Lan , GVC. Ths.

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Pile driving equipment:
diesel hammer
• More mobile and requires less time to
set up
• Economical to operate, lower
maintenance cost
• May not operate well when driving piles
into soft ground
• Noisy and oil spillage

©2010 của Đỗ Thị Xuân Lan , GVC. Ths.

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Pile driving equipment:
hydraulic hammer

source: />
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Pile driving equipment:
Hydraulics hammer
• Operate on the differential pressure of
hydraulic fluid
• The drivers develop up to 140 tons of
pressing or extracting force, make
minimal noise and cause very little
vibration
• Suited in areas where there is restricted
overhead space

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Pile driving equipment:
vibro-driving

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Pile driving equipment:
vibro-driving
• Effective in driving piles into watersaturated noncohesive soils
• The vibration are transmitted to the pile
and from the pile to the adjacent soil →
reduces the skin friction between the
soil and the pile → The combined dead
weight of the pile and the driver drive
the pile rapidly

©2010 của Đỗ Thị Xuân Lan , GVC. Ths.

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Pile driving equipment:
jacking

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The installing process for
in-situ hollow piles

©2010 của Đỗ Thị Xuân Lan , GVC. Ths.

source: Riley và Cotgrave, 2004, tr. 138
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Chapter 6. Piling work

THE INSTALLING PROCESS FOR
NON-DISPLACEMENT PILES
©2010 của Đỗ Thị Xuân Lan , GVC. Ths.

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Nondisplacement piles advantages
• Lenghth can be varied
• Soil removed during boring can be
analysed for comparison with site
investigation data
• Drilling tools can break up obtructions
which can not be penetrated by any form of
displacement pile
• Material forming pile is not governed by
handling or driving stresses

• Can be installed in very long lengths
• Can be installed without appreciable noise
or vibration
©2010 của Đỗ Thị Xuân Lan , GVC. Ths.

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Nondisplacement piles disadvantages
• Concrete in shaft susceptible to
squeezing or necking in soft soils
• Special techniques needed for
concreting in water-bearing soils
• Concrete cannot be really inspected
after installation
• Drilling a number of piles in group may
cause loss of ground and settlement of
adjacent structures
©2010 của Đỗ Thị Xuân Lan , GVC. Ths.

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