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The objective of this research was to analyse the tensile response of three geosynthetics, to apply constitutive equations, and propose values for model parameters to represent the nonlinear behaviour of these materials in the short-term, supported by statistical analysis. Data for specimens of a nonwoven geotextile, a woven geogrid and a reinforcement geocomposite previously submitted to mechanical damage, abrasion damage, and mechanical damage followed by abrasion damage were analysed. Nonlinear regressions of the experimental results were performed to fit the load vs. strain curves to constitutive equations. For each geosynthetic, the results of damaged specimens were statistically compared to those of the undamaged ones to observe the influence of the induced damage on the tensile behaviour of the material. Experimental results were statistically compared with those obtained by the constitutive models to verify if the tensile properties and the model parameters were properly estimated. For the geotextile, significant changes in tensile properties were noticed only after sequential mechanical damage and abrasion damage. For the geogrid and the reinforcement geocomposite, abrasion damage was predominant due to considerable changes in the tensile properties and the shape of the load vs. strain curves. In general, the polynomial models fitted the ultimate tensile strength slightly better, while the hyperbolic-based models presented better approximation of the secant stiffness. For hyperbolic-based models, estimating curves for damaged materials from model parameters of undamaged specimens by applying adjustment coefficients and reduction factors allowing for damage was considered promising, with slight differences for average and median curves. Contrary to the literature, model parameter α was not a material constant, as it varied according to the material condition and the shape of the load vs. strain curve. This work was supported by national funds through the FCT – Foundation for Science and Technology, by means of the doctoral scholarship with the reference 2020.07874.BD. This work was supported by national funds through the FCT – Foundation for Science and Technology - Aveiro Research Centre for Risks and Sustainability in Construction (RISCO), Universidade de Aveiro, Portugal [FCT/UIDB/ECI/04450/2020]. This work was supported by national funds through the FCT/MCTES (PIDDAC) – Foundation for Science and Technology - CONSTRUCT, Instituto de I&D em Estruturas e Construç˜oes [FCT/UIDB/04708/202 info:eu-repo/semantics/publishedVersion |
