Experimental Investigation Of Bamboo-Filled Aluminium Tube Subjected To Quasi-Static Loading.

i

EXPERIMENTAL INVESTIGATION OF BAMBOO-FILLED ALUMINIUM
TUBE SUBJECTED TO QUASI-STATIC LOADING

JOSEPH TIONG KING ING

This report is implemented as to fulfill the requirement of the title of Bachelor in
Mechanical Engineering (Structure and Materials)

FACULTY OF MECHANICAL ENGINEERING
UNIVERSITI TEKNIKAL MALAYSIA MELAKA

APRIL 2010

ii

PAGE OF CONFESSION

“I admitted that this report is the work of my own except each summary and
extraction which I had explained its sourse.”


Signature

: ........................................

Writer‟s Name

: …………………………..

Date

: …………………………..

iii

ACKNOWLEDGEMENT

First of all, I all would like to express our deeply thankfulness to God because
I manage to finish this “Projek Sarjana Muda 2” (PSM 2) report on time and could
submit it to fulfill the requirements of the subject of “Projek Sarjana Muda 2”

(BMCU 4983).

Besides that I also like to state my gratitude to everyone who has assisted and
guided me in producing this report especially to my beloved Supervisor, Prof Dr. Md
Radzai Bin Said. He had advices me how to carry out the study on “Experimental
Investigation of Bamboo-Filled Aluminium Tube Subjected to Quasi-Static Loading”.
Besides that, I would also like to share my gratitude to the Laboratory‟s
technician, Mr. Faizol Bin Kamarul Zahari and Mr. WanSaharizal Bin Wan Harun.
They were willing to arrange a time for me to perform any experimental test

Finally I also like to express my gratitude to any other individuals or group
who I have not mentions that has also played an important role in my PSM 2 report.
I hope that my PSM 2 report will fulfill the conditions as requested in “Projek
Sarjana Muda 2” (BMCU 4983). Thank you.

iv

ABSTRACT

The research involved experimental works of axial compression of

aluminium hollow square tube and bamboo-filled under quasi-static loading
condition. The main purpose of the research is to compare the energy absorption
between hollow tube and bamboo-filled tube. Initially, related journals and articles
were obtained through any resources. Total of eighteen specimens of aluminium
with different cross-section dimension were cut off with 300mm in length (9
specimens) and 150mm (9 specimens).

The cut area is ensured flat and

perpendicular to the length of the tube. Bamboo specimens are all oven-dry. After
bamboo specimens had been oven-dry, it is cut into slides. Six specimens with
length of 150mm are filled in with slides bamboo. All the specimens (empty tube
and bamboo-filled tube) were then subjected to compression load by using
INSTRON Universal Testing Mesin Model 5585. The rate of compression is 10mm
per minute.

Throughout the compression period, photos are taken with every

increment and decrement of the load-displacement curve. Videos were recorded
throughout entire compression process. This is to obtain the fold formation of the

compressed tube. After compression, data and results of the compression test were
obtained and load-displacement graphs are drawn to determine the total energy
absorption of the tube (area under curve).

v

ABSTRAK

Tajuk penelitian eksperimental melibatkan mampatan axial pembebanan
kuasi-statik balang aluminium persegi berongga dan buluh diisi.

Tujuan utama

penelitian ini adalah untuk membandingkan penyerapan tenaga antara balang hampa
dan balang buluh diisi.

Pada permulaaan, jurnal dan artikel yang berkaitan

diperolehi melalui sumber maklumat. Lapan belas spesimen dari aluminium dengan
dimensi penampang yang berbeza dipotong dengan panjang 300mm (9 spesimen),

dan 150mm (9 spesimen). Kawasan memotong dipastikan datar dan bersudut tegak
terhadap panjang balang. Semua buluh spesimen dioven-keringkan.

Setelah

spesimen buluh telah dioven-keringkan, buluh tersebut dipotong. Seterusnya, enam
spesimen dengan panjang 150mm diisikan dengan buluh yang telah dipotong.
Kemudiannya, semua spesimen (balang kosong dan balang berisi buluh) mengalami
mampatan pada mesin mampatan Instron Universal Testing Mesin Model 5585.
Kadar mampatan ditetapkan pada 10mm setiap minit. Seluruh tempoh mampatan,
foto diambil dengan setiap peningkatan dan penurunan dari graph beban-perpindahan.
Video dirakam

sepanjang proses mampatan dijalankan.

Ini adalah untuk

mendapatkan pembentukan lipatan balang dibuka. Selepas process mampatan, data
hasil kompresi diperolehi dan beban-perpindahan grafik dilukis untuk menentukan
jumlah penyerapan tenaga pada baling hampa dan baling berisi buluh (kawasan di

bawah lengkung).

vi

TABLE OF CONENT

CHAPTER

CHAPTER 1

CHAPTER 2

CONTENT

PAGE

TITLE

i


CONFESSION

ii

ACKNOWLEDGEMENT

iii

ABSTRACT

iv

ABSTRAK

v

TABLE OF CONTENT

vi


LIST OF TABLE

ix

LIST OF FIGURE

x

LIST OF SYMBOL

xviii

INTRODUCTION

1

1.1

Background


1

1.2

Objective

5

1.3

Scope

5

1.4

Problem Statement

6


1.5

Project Methodology

6

LITERATURE REVIEW

7

2.1

Energy Absorption

7

2.1.1

Quasi-Static Loading


9

2.1.2

Dynamic Loading

10

2.1.3

Oblique Loading

11

vii

CHAPTER

CHAPTER 3

CHAPTER 4

CONTENT

PAGE

2.2

Test Specimen Shape (Structural Shape)

14

2.2.1

Circular Tube

14

2.2.2

Square Tube

17

2.2.3

Frusta

18

2.3

Mode of Deformation

20

2.4

Bamboo

22

2.4.1

The Stem of Bamboo

23

2.4.2

Branch of Bamboo

24

2.4.3

Bamboo‟s Moisture Content

25

2.4.4

Bamboo‟s Dry Density

25

2.4.5

Bamboo‟s Shrinkage

26

EXPERIMENTAL DEVELOPMENT

27

3.1

Preparation of Specimen

27

3.1.1

Empty Square-shape Tube

27

3.1.2

Bamboo Specimen

28

3.2

Quasi-Static Loading

29

3.2.1

Empty Square Tube

29

3.2.2

Bamboo-Filled Square Tube

30

3.2.3

Load-Displacement Curve

31

EXPERIMENTAL RESULTS AND

32

DISCUSSION
4.1

Experimental Observation

32

4.2

Bamboo

61

4.3

The

Length

of

Bamboo-Filled

61

Aluminium Tube.
4.4

Fold Formation Process, LoadDisplacement Curves and Crush
Characteristic.

62

viii

CHAPTER

CONTENT
4.5

CHAPTER 5

PAGE

Energy Absorption Capability

63

4.5.1 Hollow Tube.

64

4.5.2 Bamboo

65

4.5.3 Bamboo-Filled Tube

65

CONCLUSION AND RECOMMENDATION

67

5.1

Conclusion

67

5.2

Recommendation

68

REFERENCE

69

APPENDIX

72

Appendix A : Aluminium Square Tube Cross

72

Section with Length= 300mm.
Appendix B : Aluminium Square Tube Cross

73

Section with Length = 150mm.
Appendix C : Flow Chart of PSM 1 (PSM 2)

74

Activities.
Appendix D : Grant Chart of Activities Carry
Out in PSM 2

75

ix

LIST OF TABLE

TABLE

TITLE

PAGE

4.1

Summary of Solid Bamboo Specimen Property

55

4.2

Summary of The Result For Hollow Aluminium

56

Square Tube.
(t=1.5mm, L=300mm)

4.3

Summary of the Result for Hollow Aluminium
Square Tube (

4.4

57

=100mm)

Summary of the Result of Density For Bamboo-

58

Filled Aluminium Square Tube
(L=150mm)

4.5

Summary of the Comparison Results For Both

59

Empty and Bamboo-Filled Aluminium Square
Tube (L= 150mm)

4.6

Summary of the Comparison Results For Both
Empty and Bamboo-Filled Aluminium Square
Tube (L= 150mm and

=13mm)

60

x

LIST OF FIGURE

FIGURE TITLE

1.1

Symmetric axial crush response mode – ductile

PAGE

3

metallic alloy, square box component: (a) axial
crush and undeformed tube specimens, (b) curve
sections and (c) crush characteristics.
(Source: Dipaolo and Tom, 2006)

1.2

Configuration A response – prototype specimen

4

S1-18: fold formation and load–displacement
curve.
(Source: Dipaolo and Tom, 2006)

2.1

Test Specimen Geometry and Support Conditions

9

(Source: Tarigopula et al., 2006)

2.2

Oblique Loading of Column

12

(Source: Reyes et al., 2003)

2.3

Test Rig

12

(Source: Reyes et al., 2003)

2.4

Deformation Modes of Oblique Loading
(Source: Reyes, et al., 2003)

13

xi

FIGURE TITLE

2.5

PAGE

Sample Specimen‟s Deformation of Oblique

13

Loading
(Source: Reyes et al., 2003)

2.6

Typical load–detection curve for an axially loaded
thin-walled

metal

tube

which

collapsed

14

by

progressive folding.
(Source: Guillowa et al., 2001)

2.7

Schematic axial view of non-symmetric or

15

diamond collapse mode. Two cases are shown, N =
3 and4 circumferential lobes.
(Source: Guillowa et al., 2001)

2.8

Axi-symmetric collapse mechanism assumed by

15

Alexander
(Source: Guillowa et al., 2001)

2.9

Axi-symmetric model used by Abramowicz and

16

Jones.
(Source: Guillowa et al., 2001)

2.10

Tube Deformation Response Mode

17

(Source: Dipaolo and Tom, 2006)

2.11

(a) Geometrical details of specimen and (b)

19

specimens before test.
(Source: Gupta et al., 2006)

2.12

Load-Deformation Curve For Frusta
(Source: Gupta et al., 2006)

19

xii

FIGURE TITLE

2.13

PAGE

Axisymmetric concertina mode and Cut view of

21

concertina mode.
(Source: Pled et al., 2007)

2.14

Diamond 3 lobe mode and Bottom view of

21

diamond mode
(Source: Pled et al., 2007)

2.15

The structural of Bamboo

23

(Source: Wong, K. M., (2004)

2.16

Bamboo‟s

Branch

Complements:

(A)

many

24

branches from many individual primary buds, (B)
many slender branches from a single primary bud,
(C) dominant primary branch and smaller branches
proliferating from its base, (D) pair of unequal
main branches from one primary bud, and (E) three
subequal main branches arising together.
(Source: Wong, K. M., 2004)

3.1

Quasi-Static Axial Crush: (a) Square Tube

29

Geometry (L=300mm) and (b) Square Tube
Geometry (L=150mm)

3.2

Instron Universal Testing Machine

31

4.1

Final Permanent Fold Formation of specimen

33

(a) 1A-1C, (b) 2A-2C, (c) 3A-3C; and (d) 1D, 2D,
and 3D.

xiii

FIGURE TITLE

4.2

Final Permanent Fold Formation of bamboo filled

PAGE

33

specimen (a) 1i-1ii, (b) 2i-2ii, and (c) 3i-3ii.

4.3

Fold Formation and Load-Displacement Curve of

34

Hollow specimen
(a) 1A, (b) 2C, and (c) 3C with L=300mm.

4.4

Fold Formation and Load-Displacement Curve of

35

Bamboo-Filled specimen (a) 1D, (b) 2D, and (c)
3D with L=150mm.

4.5

Fold Formation of Tube 1A (38X38mm) with

36

L=300mm in Load-Displacement Curve Under
Quasi-Static Loading.

4.6

Deforming Mode For Tube 1A Under Quasi-Static

36

Loading.

4.7

Fold Formation of Tube 2C (44.5X44.5mm) with

37

L=300mm in Load-Displacement Curve Under
Quasi-Static Loading.

4.8

Deforming Mode For Tube 2C Under Quasi-Static

37

Loading.

4.9

Fold Formation of Tube 3C (51X51mm) with

38

L=300mm in Load-Displacement Curve Under
Quasi-Static Loading.

4.10

Deforming Mode For Tube 3C Under Quasi-Static
Loading.

38

xiv

FIGURE TITLE

4.11

PAGE

Fold Formation of Tube 1D (38X38mm) with L=

39

150mm in Load-Displacement Curve Under QuasiStatic Loading.

4.12

Deforming Mode For Tube 1D Under Quasi-Static

39

Loading.

4.13

Fold Formation of Tube 2D (44.5X44.5mm) with

40

L= 150mm in Load-Displacement Curve Under
Quasi-Static Loading.

4.14

Deforming Mode For Tube 2D Under Quasi-Static

40

Loading.

4.15

Fold Formation of Tube 3D (51X51mm) with L=

41

150mm in Load-Displacement Curve Under QuasiStatic Loading.

4.16

Deforming Mode For Tube 3D Under Quasi-Static

41

Loading.

4.17

Fold Formation of Bamboo Ax (with L= 300mm)

42

in Load-Displacement Curve Under Quasi-Static
Loading.

4.18

Deforming Mode For Bamboo Ax Under Quasi-

42

Static Loading.

4.19

Load-Displacement

Curve

for

Bamboo-filled

Square Tubes 1a (38X38mm) with L=150mm.

43

xv

FIGURE TITLE

4.20

PAGE

Deforming Mode For Bamboo-Filled Square Tube

43

1a Under Quasi-Static Loading.

4.21

Load-Displacement

Curve

for

Bamboo-Filled

44

Square Tubes 1b (38X38mm) with L=150mm.

4.22

Deforming Mode For Bamboo-Filled Square Tube

44

1b Under Quasi-Static Loading.

4.23

Load-Displacement

Curve

for

Bamboo-Filled

45

Square Tubes 2a (44.5X44.5mm) with L=150mm.

4.24

Deforming Mode For Bamboo-Filled Square Tube

45

2a Under Quasi-Static Loading.

4.25

Load-Displacement

Curve

for

Bamboo-Filled

46

Square Tubes 2b (44.5X44.5mm) with L=150mm.

4.26

Deforming Mode For Bamboo-Filled Square Tube

46

2b Under Quasi-Static Loading.

4.27

Load-Displacement

Curve

for

Bamboo-Filled

47

Square Tubes 3a (51.0X51.0mm) with L=150mm.

4.28

Deforming Mode For Bamboo-Filled Square Tube

47

3a Under Quasi-Static Loading.

4.29

Load-Displacement

Curve

for

Bamboo-Filled

Square Tubes 3b (51.0X51.0mm) with L=150mm.

48

xvi

FIGURE TITLE

4.30

PAGE

Deforming Mode For Bamboo-Filled Square Tube

48

3b Under Quasi-Static Loading.

4.31

Comparison of Load-Displacement Curve of All

49

Empty Tube Specimen 1 with constant length,
38mm X 38mm cross-section, thickness 1.5mm,
and compression displacement of 220mm.

4.32

Comparison of Load-Displacement Curve of All

49

Empty Tube Specimen 1 with constant length,
44.5mm

X

44.5mm

cross-section,

thickness

1.5mm, and compression displacement of 220mm.

4.33

Comparison of Load-Displacement Curve of All

50

Empty Tube Specimen 1 with constant length,
51mm X 51mm cross-section, thickness 1.5mm,
and compression displacement of 220mm.

4.34

Comparison of Load-Displacement Curve for All

50

Empty Tube Specimen 1 with 38mm X 38mm
cross-section, thickness 1.5mm corresponding to
compression displacement of 100mm.

4.35

Comparison of Load-Displacement Curve of All
Empty Tube Specimen 2 of 44.5 mm X 44.5 mm
with

thickness

1.5

mm

corresponding

compression displacement of 100mm.

to

51

xvii

FIGURE TITLE

4.36

Comparison of Load-Displacement Curve of All

PAGE

51

Empty Tube Specimen 3 of 51 mm X 51 mm with
thickness 1.5 mm corresponding to compression
displacement of 100mm.

4.37

Comparison of Load-Displacement Curve of

52

Empty Tube (1D) and Bamboo-Filled Tubes (1a
and 1b) with Cross-section 38 mm X 38 mm.

4.38

Comparison of Load-Displacement Curve of

52

Empty Tube (2D) and Bamboo-Filled Tubes (2a
and 2b) with Cross-section 44.5 mm X 44.5 mm.

4.39

Comparison of Load-Displacement Curve of

53

Empty Tube (3D) and Bamboo-Filled Tubes (3a
and 3b) with Cross-section 51 mm X 51 mm.

4.40

Comparison of Load-Displacement Curve of

53

Empty Tube (1D) and Bamboo-Filled Tubes (1a
and 1b) with Cross-section 38 mm X 38 mm and
compression displacement of 13mm.

4.41

Comparison of Load-Displacement Curve of

54

Empty Tube (2D) and Bamboo-Filled Tubes (2a
and 2b) with Cross-section 44.5 mm X 44.5 mm
and compression displacement of 13mm.

4.42

Comparison of Load-Displacement Curve of
Empty Tube (3D) and Bamboo-Filled Tubes (3a
and 3b) with Cross-section 51 mm X 51 mm and
compression displacement of 13mm.

54

xviii

LIST OF SYMBOL

Pmax

=

peak load, N

Pmean

=

mean or average load, N

EA

=

energy absorption, Nmm

=

axial displacement, mm

t

=

thickness, mm

L

=

length, mm

A

=

area, mm2

Mc

=

moisture content, %

m0

=

initial mass of the test specimen, g

m0

=

final mass of specimen after oven-dry, g

D

=

density of test specimen, kg/m3

m

=

mass of specimen after dry, g

V

=

volume of the test specimen after dry, mm3

SH

=

shrinkage of the test specimen, %

I

=

initial diameter or length, mm

F

=

final diameter or length, mm

=

material yield strength, MPa

Pm

=

average folding force, N

h

=

wall thickness of the column, mm

C

=

the half length of every edge in the square cross section, mm

1

CHAPTER 1

INTRODUCTION

1.1

Background

Based on reference [1], the axial crush response of thin-wall, ductile metallic
alloy components (specific geometry and material combination) have been
extensively studied for irreversible directional energy absorption capability. It had
been studied by Coppa [2], Ezra and Fay [3], Johnson and Reid [4], and finally Reid
and Reddy [5]. Due to the significant energy can be absorbed by plastic deformation
during the progressive fold formation process that is characteristic of this response,
axial crush has many important engineering safety applications in areas including
crashworthiness and blast-resistant design of structures.

In early time, an example of the symmetric axial crush response mode by
Abramowicz and Jones for an AISI 304 stainless steel, welded square box
component tube specimen is shown in Figure 1.1. A crush specimen showing the
fold formation and an undeformed tube specimen are shown in Figure 1.1(a). The
corresponding axial load-axial displacement curve (subsequently referred to as the
load–displacement curve) is shown in Figure 1.1(b) and (c). As also mentioned in
reference [1], the axial crush response can be considered to consist of phases or
stages. The type of response shown in Figure 1.1 is divided into an „initial‟ phase
and a „secondary‟ phase. The initial phase phase includes the pre-collapse response
prior to the occurrence of the peak or maximum load, the change from axial to
bending load-resistance in the sidewalls, and the formation of the first few interior

2

and exterior folds on sets of opposite sidewalls with corresponding increases and
decreases in the load–displacement curve. The secondary folding phase consists of
the „„steady state‟‟ fold formation process and the adjacent sidewall interactions and
contacting of folds produce subsequent fold formations of constant wavelength along
the remaining length of the specimen. Therefore, a cycle in the curve (Figure 1.1(b))
corresponds to the formation of one exterior or one interior fold on both sets of
opposite sidewalls with load magnitudes fluctuating between minimum and
maximum values. The cycles can be further divided into sections with each section
represents the formation of an exterior fold on a specific set of opposite sidewalls
and the corresponding formation of an interior fold on the other opposite sidewall
pair.
For axial crush response, investigators have used or defined „„crush
characteristics‟‟, also called indicators or parameters, to evaluate and compare the
performance of components.

These characteristics include both direct data and

derived quantities. The emphasis of the current investigation is on the direct data
quantities from the load–displacement curve. The characteristics of interest are
shown in Figure 1.1(c) for the square box component and include: the initial phase
peak load, Pmax (or P02); maximum and minimum loads, Pij; mean or average loads,
Pmeani; energy absorptions, EAi; and axial displacements, �� . The subscript i refers to

the initial phase if i = 0 and the ith cycle in the secondary phase for i = 1, 2, etc. The

subscript j is a sequential number indicator for the maximum and minimum loads in
the initial phase or in an ith cycle. In general, an energy absorption quantity, EAi, is
the area under the load–displacement curve, and �

�� �

is equal to the energy

absorption divided by the axial displacement, �� for the initial phase or the ith cycle.
The axial crush response has been investigated with respect to types of
response modes, geometry-material design criteria for components, crush
characteristics to evaluate performance, methods to initiate or modify response, and
rate and temperature effects. The effects of material type, material alloying, and
process parameters were also investigated on the axial crush response of metallic
alloy components. The results shown response mode changes from ductile fold
formation to fracture, differences in mode response and crush characteristic
magnitudes in the fold formation process.

3

The analyses involved peak load and overall crush displacement and energy
absorption quantities. Secondary folding phase characteristics and details of the
materials undergoing severe plastic deformation could not be evaluated because of
significant differences in the fold formation process and the load–displacement curve
shapes for specimens within each individual study.

Figure 1.1: Symmetric axial crush response mode – ductile metallic alloy, square box
component: (a) axial crush and undeformed tube specimens, (b) curve sections and (c)
crush characteristics.
(Source: Dipaolo and Tom, 2006)

The term „„configuration response‟‟ was introduced in previous research
involving AISI 304 stainless steel square box components by DiPaolo [1]. For the
symmetric axial crush mode, a specific „„configuration response‟‟ refers to the
combination of a specific fold formation process (verified by fold appearance) and
the shape of the corresponding load–displacement curve.

An example of fold

formation and the corresponding load–displacement curve of an AISI 304 stainless
steel tube specimen for the „„Configuration A‟‟ response that was studied in the

4

previous research [1] is given in Figure 1.2. The results of the research showed that
there were several configuration responses of the symmetric axial crush mode and
that these configuration responses differed in stationary fold-line locations and
traveling fold-line paths for right-circular cylindrical polyvinyl chloride specimens,
idealized models, plastic „„hinge lines‟‟, and for right-circular cylindrical and square
specimens. Therefore, there were differed in load magnitudes, energy absorption
processes and material performance requirements.

It had demonstrated that axial crush response could be controlled and
restricted to a specific configuration response for tube specimens with constant
geometry and material and, also, for tube specimens with constant geometry and of
the same alloy, but having different uniaxial tensile strength levels.

This capability is important not only for the practical application of axial
crush response, but also because it provides the ability to research the influence of
material parameters on axial crush characteristic magnitudes and to study details of
material behavior such as microstructural evolution and deformation mechanisms
during severe plastic deformation.

Figure 1.2: Configuration A response – prototype specimen S1-18: fold formation
and load–displacement curve.
(Source: Dipaolo and Tom, 2006)

5

1.2

Objective

The main objective of this research is focused on the capability of the
bamboo-filled and hollow empty square aluminium tube to absorb energy during
compression. Different cross-section with constant wall thickness and length were
studied and tested to compare the behavior of its capability in energy absorption.

In order to achieve the above goal, each tube was investigated its peak and
mean loads, plastic folding and energy absorbed of bamboo-filled hollow empty
aluminium tube subjected to axial compression.

In additional, the study also

compared empty and bamboo-filled tube with respect to energy absorption.

1.3

Scope

Aluminium thin-walled tube is selected as the experiment specimen. For
comparison among the empty tubes, the tube had three different cross section
dimensions but had same thickness and length of 1.5mm and 300mm. While for
comparison between empty and bamboo-filled tubes, the length of the tube is
decrease to 150mm. The type of bamboo chosen is Dendrocalamus Asper. All
specimens subjected quasi-static loading with compression speed of 10mm per
minute. The characteristic of the empty tube for each cross section is determine
through its‟ peak and mean loads, number of plastic folding, and capability of energy
absorbed. As for the characteristic between empty tube and bamboo-filled tube, the
specimen‟s peak and mean loads, and the capability of energy absorbed are also been
determine. No simulation work performed in this particular task.