Showing 5 results for Fibers
H. Oucief, M.f. Habita, B. Redjel,
Volume 4, Issue 2 (6-2006)
Abstract
In most cases, fiber reinforced self-compacting concrete (FRSCC) contains only one type
of fiber. The use of two or more types of fibers in a suitable combination may potentially not only
improve the overal properties of self-compacting concrete, but may also result in performance
synergie. The combining of fibers, often called hybridization, is investigated in this paper for a
cimentetious matrix. Control, single, two fibers hybrid composites were cast using different fiber
type steel and polypropylene with different sizes. Flexural toughness tests were performed and
results were extensively analysed to identify synergy, if any, associated with various fiber
combinations. Based on various analysis schemes, the paper identifies fiber combinations that
demonstrate maximum synergy in terms of flexural toughness.
Hasan Ghasemzadeh, Ms. Esmat Akbari Jalalabad,
Volume 9, Issue 3 (9-2011)
Abstract
In this study compressive strength of carbon nanotube (CNT)/cement composite is computed by analytical method. For this purpose representative elementary volume (REV) as an indicator element of composite is chosen and analyzed by elasticity relationships and Von mises' criterion applied to it. It is assumed that carbon nanotubes are distributed uniformly in the cement and there is perfect bonding in the interface of cement and nanotube. At first for simplicity of computations, carbon nanotubes ( CNTs) are assumed to have unidirectional orientation in the cement matrix. In following, the relations are generalized to consider random distribution of nanotubes in cement, and a new factor suggested for random orientation of fibers in the CNT/cement composite. The results of analytical method are compared with experimental results.
M. Khorami, J. Sobhani,
Volume 11, Issue 4 (12-2013)
Abstract
Worldwide, asbestos fibers utilized in fiber cement boards, have been recognized as harmful materials regarding the public
health and environmental pollutions. These concerns motivate the researchers to find the appropriate alternatives to substitute
the asbestos material towards the sustainability policies. In this paper, the applicability of asbestos replacement with three
types of agricultural waste fibers, including bagasse, wheat and eucalyptus fibers were experimentally investigated. To this
end, the flexural behaviour and microstructure of cement composite boards made by addition of 2 % and 4 % of waste
agricultural fibers in combination with and without 5 % replacement of silica fume by mass of cement were evaluated. The
results of this study attested the applicability of utilized waste agricultural fibers in production of cement composite boards by
improving the flexural and energy absorption characteristics, more or less, depending on the type of fibers. Moreover, it is
found that application of silica fume in production of cement composite boards led to an increase in flexural strength.
C. Gümüşer, A. Şenol,
Volume 12, Issue 2 (4-2014)
Abstract
The total coal and lignite consumption of the thermic power plants in Turkey is approximately 55 million tons and nearly
15 million tons of fly ash is produced. The remarkable increase in the production of fly ash and its disposal in an
environmentally friendly manner is increasingly becoming a matter of global concern. Studies for the utilization of fly ash in
Turkey are necessary to reduce environmental problems and avoid economical loss caused by the disposal of fly ash. Efforts
are underway to improve the use of fly ash in several ways, with the geotechnical utilization also forming an important aspect
of these efforts. An experimental program was undertaken to investigate the effects of Multifilament (MF19average) and
Fibrillated (F19average) polypropylene fiber on the compaction and strength behavior of CH class soil with fly ash in
different proportions. The soil samples were prepared at three different percentages of fiber content (i.e. 0.5%, 1% and 1.5%
by weight of soil) and two different percentages of fly ash (i.e. 10% and 15% by weight of soil). A series of tests were prepared
in optimum moisture content and laboratory unconfined compression strength tests, compaction tests and Atterberg limits test
were carried out. The fiber inclusions increased the strength of the fly ash specimens and changed their brittle behavior into
ductile behavior.
M.m. Kamal, M.a. Safan, Z.a. Etman, M.a. Abd-Elbaki,
Volume 13, Issue 4 (12-2015)
Abstract
The current research intends to study the possibility of producing fiber recycled self-compacting concrete (FRSCC) using demolitions as a coarse aggregate (crushed red brick and crushed ceramic). Steel fibers were used in recycled self-compacting concrete (RSCC) to improve fresh and hardened properties of this type of concrete. Thirty nine concrete mixes were prepared to achieve the aim proposed in this paper. Steel fiber volume fraction varied from 0 to 2.0% by the volume of concrete with aspect ratio 65. The fresh properties of FRSCC were evaluated using slump flow, J-ring and V-funnel tests. Compressive strength, tensile strength, flexural strength and density tests were performed in order to investigate mechanical properties. The optimum volume fraction of steel fibers was 0.25% and 1.0% for the mixes contained crushed red brick and ceramic as a coarse aggregate respectively. At optimum content of steel fibers, the compressive strength for the RSCC mixes with steel fibers improved by 11.3% and 31.8% for the mixes with crushed ceramic and crushed red brick, respectively with respect to control mix. Also the tensile strength and the flexural strength for the mixes were improved