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Highlights • An intrinsic cohesive zone approach is proposed for the impact failure of automotive windshield laminated glass. • Gradual energy dissipation process of glass-PVB debonding can be modeled by means of the cohesive zone model. • A windshield finite element model is developed to account for the two failure patterns, including glass fracture and glass-PVB debonding. • The effectiveness of the proposed model is validated by comparing simulation results under center and corner impact with experimental ones. • Parametric studies are conducted to investigate the effects of adhesion parameters, PVB material parameters, and impact velocities and angles on the impact fracture behavior and energy absorption performance of the windshield. Abstract Though windshield laminated glass is a simple sandwiched composite structure, it is of vital importance to investigate its damage and energy absorption behavior for the purpose of pedestrian safety protection. This paper proposes an intrinsic cohesive zone approach to achieve this end. A finite element windshield glazing model is established by inserting cohesive elements into the common surfaces between glass elements, and the interfaces between glass and PVB prior to simulations. The appeal of this model is that both of the two main failure patterns and their energy absorptions, i.e. glass fracture and glass-PVB debonding, of the windshield can be captured by means of the intrinsic cohesive zone approach. The effectiveness of the proposed model is validated by comparing the simulation results under center and corner impact with the corresponding experimental outcomes. Finally, the effects of adhesion parameters, PVB material parameters, and impact velocities and angles on the impact fracture behavior and energy absorption performance of the windshield are thoroughly investigated. [ABSTRACT FROM AUTHOR]

This paper investigates the effect of size and complexity of composite structures on the formation of low-velocity impact damage via experimental tests and numerical modelling. The ASTM standard low-velocity impact test and a scaled-up version of the test were conducted. A novel numerical technique is presented that combines 3D solid and thin 2D shell elements for modelling different domains to achieve a high level of fidelity locally under the impact location, whilst achieving good computational efficiency for large structures. Together with the experimental studies at the different scales, the predictive capability of the numerical models was systematically validated. This modelling method demonstrated an advanced computational efficiency without compromising predictive accuracy. The models are applied to a case study of low-velocity impact of a large-scale stringer-stiffened panel, showing this modelling approach to be suitable for predicating low-velocity impact damage and structural response of laminated composites over a range of sizes and complexities. [ABSTRACT FROM AUTHOR]

Abstract: This paper shows how experimental test results from a split-Hopkinson tension bar (SHTB) and numerical simulations of the test set-up can be used for mutual verification. Firstly, a SHTB where the tension stress wave is generated by pre-stretching a part of the incident bar is briefly presented. This SHTB is used to carry out tensile tests of four aluminium alloys at high rates of strain, while tests at low to medium strain rates were performed in a servo-hydraulic tensile test machine. Using the test results, the parameters of an anisotropic thermoelastic-thermoviscoplastic constitutive relation and a one-parameter fracture criterion are identified for the materials at hand. Subsequently, the material model is used in explicit finite element analyses of the SHTB tests, including the entire experimental set-up and the stress wave propagation during the test. The numerical predictions were found to represent the observed behaviour in the experimental tests fairly well. [Copyright &y& Elsevier]