Effect of untreated coal waste as fine and coarse aggregates replacement on the properties of steel and polypropylene fibres reinforced concrete

The consumption of structural concrete in the construction industry is rapidly growing, and concrete will remain the main construction material for increasing urbanization all over the world in the near future. Meanwhile, construction and demolition waste from concrete structures is also leading to a significant environmental problem. Therefore, a proper sustainable solution is needed to address this environmental concern. One of the solutions can be using recycled coarse aggregates (RCA) in reinforced concrete (RC) structures. Extensive research has been conducted in this area in recent years. However, the usage of RCA concrete in the industry is still limited due to the absence of structural regulations appropriate to the RCA concrete. This study addresses a safety margin of RCA concrete beams in terms of shear capacity which is comparable to natural coarse aggregates (NCA) concrete beams. To this end, a database for reinforced concrete beams made of recycled coarse aggregates with and without shear reinforcement was established, collecting the shear specimens available from various works in the existing literature. The database was used to statistically identify the strength margin between RCA and NCA concrete beams and to calculate its safety margin based on reliability analysis. Moreover, a comparability study of RCA beams was conducted with its control specimens and with a database for conventional RC beams.

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Polypropylene Fibre Reinforced Concrete Air Permeability

MRS Proceedings ◽

10.1557/proc-211-71 ◽

1990 ◽

Vol 211 ◽

Cited By ~ 2

Author(s):

Miguel A. Sanjuan ◽

A. Moragues ◽

B. Bacle ◽

C. Andrade

Keyword(s):

Carbon Dioxide ◽

Reinforced Concrete ◽

Steel Corrosion ◽

Air Permeability ◽

Polypropylene Fibre ◽

Fibre Reinforced Concrete ◽

Polypropylene Fibres ◽

Cement Ratio ◽

Reinforcing Steel Corrosion

AbstractThe permeability of concrete to gases is of direct importance to the durability of concrete structures, because of carbon dioxide flowing through the concrete favour lime carbonation and reinforcing steel corrosion.Mortar with and without polypropylene fibres having water/cementitious ratios of 0.30, 0.35 and 0.40 and a cement/sand ratio of 1/1 were studied. Polypropylene dosage varied from 0.1 to 0.3% by volume of cement.The characterization of mortar permeability was made using cylindrical shaped samples (3 cm height and 15 cm diameter). These specimens were 28 days cured and then dried before the test.The addition of fibres results in a decrease of air permeability. Variation of the water/cement ratio is of lesser importance than fiber addition.

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Study of the reinforcement of structure members by polypropylene fibres waste

MATEC Web of Conferences ◽

10.1051/matecconf/201814901022 ◽

2018 ◽

Vol 149 ◽

pp. 01022 ◽

Cited By ~ 1

Author(s):

Khadra Bendjillali ◽

Mohamed Chemrouk

Keyword(s):

Reinforced Concrete ◽

Significant Contribution ◽

Concrete Beams ◽

Average Diameter ◽

Concrete Surface ◽

Point Of View ◽

Reinforced Concrete Beams ◽

Polypropylene Fibres ◽

Steel Bars ◽

Material Durability

The valorisation of industrial waste in the field of construction became a very interesting axis of research from scientific, economic and environmental point of view. We have conducted this work to study the effect of the addition of polypropylene fibres waste on the mechanical behaviour of reinforced concrete beams subjected to a simple flexural loading, with and without transversal reinforcement. The used fibres are coming from the waste of the fabrication of domestic brushes and sweeps; they have an average diameter of 0.47 mm and a length between 40 and 60 mm. Two weight dosages of fibres are used, 0.25 and 0.5 %. The experimental results showed that the incorporation of polypropylene fibres waste into the concrete affects negatively its workability, but its flexural and compressive strength are improved. The fibers have presented a significant contribution on the shear behavior and the cracking of beams, particularly in absence of transversal bars. The waste used in this work as fibrous reinforcement has not only increased the ductility of reinforced concrete beams, but it have also provided a perfect cracking distribution on the concrete surface and it has participated in a considerable way in the reduction of cracks number and dimensions, which allows to ensure the material durability and then the structure longevity. The reinforcement of concrete beams with 0.5 % of polypropylene fibers waste with a minimal steel bars can ensure an excellent mechanical behavior in shear, as in flexion.

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PROPERTIES OF FRESH POLYPROPYLENE FIBRE REINFORCED CONCRETE UNDER THE INFLUENCE OF POZZOLANS

Journal of Civil Engineering and Management ◽

10.3846/13923730.2003.10531339 ◽

2003 ◽

Vol 9 (4) ◽

pp. 271-279 ◽

Cited By ~ 2

Author(s):

Hau-yan Leung ◽

Ramapillai V. Balendran

Keyword(s):

Reinforced Concrete ◽

Fly Ash ◽

Silica Fume ◽

Setting Time ◽

Polypropylene Fibre ◽

Partial Replacement ◽

Fibre Reinforced Concrete ◽

Polypropylene Fibres ◽

Fibre Concrete ◽

Time Substitution

This paper summarises experimental results of some fresh concrete tests. Polypropylene fibres were added to the concrete mix to produce fibre reinforced concrete. Pozzolanic materials, including pulverised fly ash and silica fume, were used as partial replacement of cement, and their effects on the fresh fibre concrete were reported. Test results showed that the polypropylene fibre reduced the concrete workability significantly by thixotropic effect and decreased the setting time. Substitution of pozzolans also greatly affected the properties. The presence of fly ash increased the workability and setting time but in the presence of silica fume a reverse trend was observed. Empirical equations were proposed.

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Long-term flexural performance of reinforced concrete beams with recycled coarse aggregates

Construction and Building Materials ◽

10.1016/j.conbuildmat.2018.05.069 ◽

2018 ◽

Vol 176 ◽

pp. 593-607 ◽

Cited By ~ 21

Author(s):

Sindy Seara-Paz ◽

Belén González-Fonteboa ◽

Fernando Martínez-Abella ◽

Diego Carro-López

Keyword(s):

Reinforced Concrete ◽

Concrete Beams ◽

Reinforced Concrete Beams ◽

Flexural Performance ◽

Coarse Aggregates

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Performance evaluation of E-waste and Jute Fibre reinforced concrete through partial replacement of Coarse Aggregates

Materials Today Proceedings ◽

10.1016/j.matpr.2020.10.689 ◽

2020 ◽

Author(s):

R. Rajkumar ◽

V. Navin Ganesh ◽

S.R. Mahesh ◽

K. Vishnuvardhan

Keyword(s):

Performance Evaluation ◽

Reinforced Concrete ◽

Partial Replacement ◽

Fibre Reinforced Concrete ◽

Jute Fibre ◽

Coarse Aggregates

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Effect of recycled concrete coarse aggregates on service-load deflections of reinforced concrete columns

Engineering Structures ◽

10.1016/j.engstruct.2019.109955 ◽

2020 ◽

Vol 204 ◽

pp. 109955 ◽

Cited By ~ 2

Author(s):

Adam M. Knaack ◽

Yahya C. Kurama

Keyword(s):

Reinforced Concrete ◽

Concrete Columns ◽

Recycled Concrete ◽

Reinforced Concrete Columns ◽

Coarse Aggregates ◽

Service Load

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Shrinkage Behaviour of Fibre Reinforced Concrete with Recycled Tyre Polymer Fibres

International Journal of Polymer Science ◽

10.1155/2015/145918 ◽

2015 ◽

Vol 2015 ◽

pp. 1-9 ◽

Cited By ~ 16

Author(s):

Marijana Serdar ◽

Ana Baričević ◽

Marija Jelčić Rukavina ◽

Martina Pezer ◽

Dubravka Bjegović ◽

...

Keyword(s):

Reinforced Concrete ◽

Drying Shrinkage ◽

Fibre Reinforced Concrete ◽

Restrained Shrinkage ◽

Polypropylene Fibres ◽

Concrete Mixtures ◽

Shrinkage Behaviour ◽

Different Types ◽

Waste Tyre ◽

Recycled Polymer

Different types of fibres are often used in concrete to prevent microcracking due to shrinkage, and polypropylene fibres are among the most often used ones. If not prevented, microcracks can lead to the development of larger cracks as drying shrinkage occurs, enabling penetration of aggressive substances from the environment and reducing durability of concrete structures. The hypothesis of the present research is that polypropylene fibres, used in concrete for controlling formation of microcracks due to shrinkage, can be replaced with recycled polymer fibres obtained from end-of-life tyres. To test the hypothesis, concrete mixtures containing polypropylene fibres and recycled tyre polymer fibres were prepared and tested. Experimental programme focused on autogenous, free, and restrained shrinkage. It was shown that PP fibres can be substituted with higher amount of recycled tyre polymer fibres obtaining concrete with similar shrinkage behaviour. The results indicate promising possibilities of using recycled tyre polymer fibres in concrete products. At the same time, such applications would contribute to solving the problem of waste tyre disposal.

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