Page 54 - New Trends in Green Construction

Circular Economy
Flexural tensile strength: the studies conducted to evaluate the flexural tensile strength in concretewith PFledtotheconclusionthattheresistancedecreasesastheamountofaddedfibers increases (López-Buendía, 2013, Pelisser, 2012). This decrease tends to be reduced using low percentagesofplasticfibers(Ruiz-Herrero, 2016).
Durability: the addition of plastic fibers in the concrete, affects the durability of the mixture and, particularly, on shrinkage, porosity, and the possibility of entering gaseous or liquid substances into the concrete. Regarding the shrinkage, the results of the tests carried out byvariousscholarsareconflicting.Some showedadecreaseinshrinkageoftheconcretewithPF with an increase in the fibers content (Karahan, 2011). On the contrary, others have seen an increase in shrinkage with the increase of the plastic aggregate (Kim, 2010). The tests conductedontheporosityoftheconcretecontainedPFsshowsthattheporosityincreaseas the amount of PF rises (Karahan, 2011). According to the previous studies (Kakooei, 2012), the dosage of PF not have a significant influence on the possibility of entry of gaseous or liquid substances into concrete.
3. Results and conclusions
The use of plastic and recycled plastic macro fibers certainly leads to positive results with regard to the protection of the environment as it significantly reduces the amount of waste taken to landfill. As it has been shown, many research works have been developed with the main objective of reusing recycled plastic fibers as a construction material. This research field is gaining widespread attention due to the large amount of plastic materials that our society consumes daily. The conclusions of the present work are that it is feasible to revalue plastic wastes as recycled plastic fibers for being used in concrete manufacturing, improving the concrete properties. More conflicting (and certainly to be continued and deepen) are the research on the physical and mechanical characteristics of the mixture between concrete and plastic fibers. In order to obtain univocal results, thus realizing a fully usable material in the field of structural and non-structural constructions, and with characteristics equivalent or superior to concrete made only with natural aggregate. Thus, the road ahead is to continue in the investigations and experiments in this framework.
4. Acknowledgment
Thanks to all the authors who have carried out the studies and experiments mentioned in the present work.
5. References
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