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Preliminary experimental investigation into the use of recycled fibres from textile waste for the improvement of embankments

Rossignoli Chiara, Caruso Marco, Jommi Cristina, Sterpi Donatella

Journal of Water and Land Development

2023

no. 59

202--207

Failures that occurred in the last few decades highlighted the need to raise awareness about the emergent risk related to the impact localised degradation phenomena have on embankments. Common interventions aimed to improve embankments, such as the reconstruction of the damaged area or the injection of low-pressure grouts to fill fractures and burrows, may cause the weakening of the structure due to discontinuities between natural and treated zones. Moreover, since such repair techniques require huge volumes of materials, more sustainable solutions are encouraged. At the same time, the textile and fashion industries are looking for sustainable waste management and disposal strategies to face environmental problems concerned with the voluminous textile waste dispatched to landfills or incinerators. The use of soil mixed with textile waste in embankment improvement has been investigated to identify an effective engineering practice and to provide a strategy for the circular economy of textiles. Preliminary laboratory tests have been conducted on soil specimens collected from the Secchia River embankment, Northern Italy, to define the appropriate mixture proportions and to compare physical properties and hydro-mechanical behaviour of natural and treated soils. The results show that an appropriate fibre content offers manageable and relatively homogeneous mixtures. The indluence on soil consistency is mainly due to the textile fibre hydrophilic nature. The addition of fibres reduces the maximum dry density and increases the optimum water content. At low stress levels, the compressibility and hydraulic conductivity appear higher, however macro voids produced during sample preparation may alter the findings.

Ballistic performance of FRP – steel layered structures

Barnat W., Gotowicki P., Dybcio P., Gieleta R., Kosiuczenko K.

Journal of KONES

2013

Vol. 20, No. 2

15--20

In this study, the impact performance of layered structures made of aramid/epoxy, S2 glass/epoxy, Dyneema and steel subjected to high velocity impact is presented. All materials were previously examined using proper techniques of strength tests. The procedure allowed determining Young’s moduli, Poisson’s ratio, ultimate compression and tension strength, shear modulus. The ballistic test procedure was based on standards for testing panels and armour plates. For the purpose of ballistic tests, standard 5.56 NATO ammunition (183 g) was used. The aim of presented work was to determine ballistic performance of different structures under bullet impact. During the tests, subsequent time moments were recorded using Phantom V12 high-speed camera. When structure penetration did occur, the residual velocity of bullet was measured using PVM-21 lightscreen. Basing on the results, each material performance was evaluated. This paper reviewed a number of mechanisms that influence the ballistic performance of ballistic textiles. The composites reinforced with continuous fibres (aramid, S2 glass) could effectively absorb the kinematic energy of bullet. The efficiency of energy absorption for each types of material in the order from highest is as follows: polyethylene fibres Dyneema HB50, composite reinforced with S2 glass fibres, composite reinforced with aramid fibres.

Experimental and theoretical investigations of glass-fibre reinforced composite subjected to uniaxial compression for a wide spectrum of strain rates

Pieczyska E. A., Pęcherski R. B., Gadaj S. P., Nowacki W. K., Nowak Z., Matyjewski M. M.

Archives of Mechanics

2006

Vol. 58, nr 3

273-291

Results of static and dynamic compression} tests for two types of glass fibre-reinforced polypropylene composites are presented. Stress-strain curves showing the influence of the strain rate on the composite mechanical properties have been obtained. A three-dimensional description of the material behavior during the deformation has been developed. The material constitutive parameters have been calculated. Specification of the parameters and description of the methods used for their identification have been worked out. The results are discussed in terms of the deformation processes and the material non-homogeneity.