Wood Fiber Reinforced Concrete

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Nov 25, 2013 (3 years and 6 months ago)

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243
Wood Fiber Reinforced Concrete
Ductility at low costs
M.G. Sierra B
eltr
a
n
/m.g.sierra
b
eltr
an@tud
elft.nl
Erik Schlangen
/ h.e
.j.g.schlangen@tudelft.nl
erials & E
nvi
r
o
n
m
e
nt / Wood Fiber Reinf
orced Concr
e
t
e
D
elft Unive
rsity of
T
echn
o
l
ogy/ Fa
c
ulty o
f Civi
l E
n
g
i
neeri
n
g and
Geosciences
SUBJECT
Natural fibers are a re
n
ewable, a
vail
able and
low cost resource for rei
nforcing materials.
Currently, polymers, plastics and ceramics
are b
eing reinforced with wood, kenaf, flax
or h
emp fibers. For this project woo
d fibers
will be studied as rein
f
orcement in a cement
matrix for possible a
pplications in structural
elements. A micromechanics-b
a
sed design is
proposed to achiev
e a ductile material.
GOAL
To design a ductile cementitious
composite with lower production costs c
ompared to
similar products reinf
orced with artificial fibers.
EXPECTED RESULTS
A cementitious comp
o
site that c
ould be used for structural appli
c
a
tions tha
t require
controlled c
racking, sufficient ten
sile strength and/or enhanced ductility and
toughness while having l
ow cost
s
. A material that w
ould be used cast-in-pl
a
ce as
well as for prefabricated element
s
.
C
e
m
e
n
t ma
t
rix with na
t
ural fibers
-
Microla
b
C
e
m
e
n
t ma
t
r
i
x wi
t
h woo
d f
i
b
e
r
s –
E
S
E
M
Mi
c
r
o
lab
Wood fibers –
E
S
EM Micr
o
l
a
b
0
5
10
15
20
0 2 4 6
D
i
s
p
l
a
c
emen
t (mm)
Ben
ding s
tren
g
t
h (MPa)
Goal: To design a duc
tile m
aterial similar t
o this E
C
C
(Engi
n
e
e
r
ed c
e
m
entit
i
o
u
s
c
ompo
sit
e
) bea
m w
i
t
h P
V
A
f
ibers m
ade a
nd t
e
s
ted at M
i
c
rola
b
Researcher
Supervisor
Progra
m
/
Su
b
prog
r
a
m Mat
Host Uni
v
e
rsit
y
242
243
Foto
Wood fiber reinforced concrete
Ductility at low cos
t
s
M.G. Sierra Beltran
1
, Erik Schlangen
2
1
PhD Researc
her, Materials & Environment, Microlab
,m.g.sierrabelran@tudelft.n
l
t
2
Supervisor, Mat
erial
s& E
nvironment, Microlab, h.e.j.g.schlangen
@tudelft.nl
Delft Univer
s
i
ty of Technol
ogy, Faculty of Civil Engineering and Geosciences
Subject: Wood fiber rei
nforced concrete
Natural fibers are a renewable, available and low cost resource f
or reinforcing materials.Currently,
polymers, plastics and cer
amics are bei
ng reinforced with wood,kenaf, flax or hemp fibers. Worl
d
w
ide t
h
e intere
s
t to us
e the
m for concre
t
e a
nd cementitiou
s m
aterials as well is growing
,but so far
the research has been foc
used on cem
entitiou
s mat
erials only for application
s such as thin sheets an
d
non-structural building ele
ments. For this project wood fibers wil
l be studied as reinforcement in a
cement matri
x for possible application
s in structural element
s
. A micromechanics-based design is
proposed to achieve a ducti
le material.
Goals
To design a ductile cementitiou
s composite with lower productio
n costs compared to similar products
reinforced with artifici
al fibers.The material will be d
esigned throu
gh micromechanics. Thi
s is a dif-
ferent approach related to the use of natural fibers in cement matrixes.
Research Question
Is it possible to achieve enhanced ductility and tough
ness by using wood and other natural fibers as
reinforcement in a cement matrix?
Strategy
First the nature and origin of the wood fibers to be used in this project will be established acc
ording to
the mechanical and chemi
cal properties as well as the avail
ability. Then, the fiber-cemen
t matrix in
-
teracti
on par
ameter
s will be analy
sed through testing and ESEM i
mages. Later, the m
aterial will be
designed employing micromechanic
s. F
inally, the mechanical properties and durability of the concrete
shall b
e tested in the lab
o
r
atory in order to compare the res
ults w
ith t
he calcula
tions done in advance.
Special attention will be given to the distribution of fibers in the c
ement matri
x
.
Expected R
esults
A cementiti
o
u
s composite that could be used for structural applications that r
e
q
uire contr
olled crack-
ing, sufficient tensile stren
gth and/or enhanced ductility and tough
ness while having low costs. A m
a
-
terial that w
ould be used c
ast-in-place as well as for prefabricated element
s
.
Preferred Partners Applications / Sponsors
Wood industr
y/ Natural fiber producers/ Construction industry
Prime Publication / Prototyping
The results of the research will be published in journal
s and c
onferences.
Research Period
2006-2010