chapter6 Sức bền vật liệu

Đây là tài liệu của các bạn sinh viện hiện tại đang học tại Đại học Bách Khoa TP HCM. Đồng thời cũng là giáo án của giảng viên tại Đại học Bách Khoa. Nó sẽ rất hữu ích cho công việc học tập của các Bạn. Chúc Bạn thành công.

Trang 1

Construction methods and management

Chapter 6 PILING

WORK

Trang 3

Trang 4

PILE TYPES

Chapter 6 Piling work

Trang 5

Trang 6

THE INSTALLING PROCESS FOR

Trang 7

The installing process for

displacement piles

7

Trang 8

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

Trang 9

Displacement piles

-disadvantages

• May break during driving

• May suffer unseen damage which may reduce carrying capacity

9

Trang 10

Equipment for installing

Trang 11

Equipment for installing

piles

11

source: Riley và Cotgrave, 2004, tr 136

drop hammer/

diesel hammer/

hydraulic hammer

driving

vibro-jacking

Trang 12

Pile driving equipment:

drop hammer

Trang 13

• 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

13

Trang 14

diesel hammer

Trang 15

Trang 16

Trang 17

hydraulic hammer

17

source: 0712(7ton)/Hydraulic_Pile_Hammer(7ton1.2M)01.jpg

Trang 18

http://www.powerquip.co.kr/job/SGH-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

Trang 19

vibro-driving

19

Trang 20

vibro-driving

• Effective in driving piles into

water-saturated 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

Trang 21

jacking

21

Trang 22

The installing process for

in-situ hollow piles

Trang 23

THE INSTALLING PROCESS FOR NON-DISPLACEMENT PILES

23

Trang 24

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

Trang 25

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

25

Trang 26

Bored piles

• Diameter of bored pile ranges from

600mm (less than 600mm: micro bored piles)

• A continous flight, hollow shaft auger is rotated into the soil

• Bentonite is commonly used to resist the excavation

• Concreted is poured underwater with

Trang 27

1.Set out, bore the initial hole,

place the casing

2 Pump betonite which is

commonly used to resist the

excavation into the borehole

3 Proceed with boring using an

augering bit to required depth.

4 Pump out and recycle

contaminated bentonite and

pump fresh betonite into the

borehole, install steel cage and

pour concrete

5.Pour concrete to 1m higher

than the required depth

6 Complete operation after

extracting casing

Bored piles

27

source: http://www.frankipile.co.id/pic/bored-pile.jpg

Trang 28

Bored piles: augers

Cohesive soils

Trang 29

Diaphragm wall

29

Trang 30

diaphragm wall construction

Trang 31

Typical excavation

sequence of diaphragm

walls

Trang 32

Trang 33

Trang 34

Trang 35

35

source: http://www.itm-ltd.com/projects/images/Dscn0099b.jpg

Guide FGgui

Guide walls built in

advance for the trench

excavation

Trang 36

CONSTRUCTION SEQUENCE

Trang 37

Precast reinforced concrete piles

Trang 38

Trang 39

Trang 40

Trang 41

Trang 42

Precast reinforced concrete hollow piles

Trang 43

Trang 44

Trang 45

45

4 Weld

the joint

Trang 46

5 Continue

hammering

Trang 47

Trang 48

Concrete sheet piling

Trang 49

49

2 Install

guiding

frame

Trang 50

3 Hoist

up the

pile

Trang 51

Trang 52

Trang 53

Trang 54

Trang 55

Trang 56

Trang 57

CONSTRUCTION SEQUENCE

ILLUSTRATION OF STEEL SHEET

PILES

57

Trang 58

Steel sheet piling

Trang 59

Trang 60

Trang 61

Trang 62

Trang 63

63

4

Vibrating

the piles

Trang 64

Trang 65

Trang 66

7 Steel

sheet

piles

installed

Định dạng
Số trang	66
Dung lượng	2,98 MB