This paper proposes a methodology that employs an experimental apparatus that reproduces, in pre-impregnated and cured out-of-autoclave Glass Fiber Reinforced Polymer (GFRP) panels, the phenomenon of slamming or impact on the bottom of a high-speed boat during planing. The pressure limits in the simulation are defined by employing a finite element model (FEM) that evaluates the forces applied by the cam that hits the panels in the apparatus via microdeformations obtained in the simulation. The methodology requires that various impact series be performed at different energies and that the evolution of the damage be followed via immersion ultrasound inspection to quantify how the material behaves, in addition to evaluating the delamination process via penetrating dyes using UV radiation. Slamming impacts were performed on the order of 105, and the micromechanisms of interlaminar and intralaminar damage propagation were observed with scanning electron microscopy (SEM). The results were analyzed by correlating them with pressure, deformation, impact energy, and applied cycles, in addition to conducting compression experiments after impact to relate the material damage with the residual strength of the impacted panels

This study presents the option of an effective low-impact energy dissipating material applied to GFRP (glass fiber reinforced plastic) composite laminates using auxectic technology in the case of planing hull vessels that use the same high-speed light materials that repeatedly impact the surface of the water when sailing, producing a slamming phenomenon. Research shows that the option to modify the laminate with an auxectic layer protects the laminate from damage. This work proposes the manufacturing of dissipative layers, introduced in laminates made with a polymeric matrix and fiberglass reinforcement, which are evaluated with weight drop tests under different impact energies. The data are collected and processed by a unidirectional gravitometer that gives the acceleration values of the impactor. The tests compare unmodified panels with modified panels, showing that the energy absorbed by the unmodified panel is greater at equal energy levels. The returned energy comparison curve is shown, and the benefits of its use are presented.

Para el diseño de embarcaciones construidas por laminados de GFRP se propone una inserción con capa viscoelástica para disminuir la propagación del daño producido por el impacto vertical del fondo de la nave con el mar o fenómeno de slamming. Mediante comparaciones de impactos verticales por caída de peso que reproducen la energía inferida al panel durante la navegación, se estudia la propagación del daño de paneles de preimpregnado curados OoA comparándolo con paneles modificados con inserción de capa viscoelástica. El empleo de lectura de datos de aceleraciones durante el impacto permite cuantificar mediante la formulación desarrollada los beneficios de la modificación observando el comportamiento de la fuerza, el desplazamiento y la energía que devuelve el panel luego del impacto y que no se convierte en daño intralaminar e interlaminar.

This project is based on the investigation of one characteristic of a new material to improve GFRP high speed vessels constructions. The main objective is to find the debonding, that is the analyzed characteristic that is going to prove that the material works to avoid delamination in the bottom. This characteristic is studied by laboratory reproductions, by designing fiber glass specimens and modifying some of them with viscoelastic, to compare the modified and non-modified ones. The laboratory experiment is based on performing an axial force in the specimen until it separates. By analyzing the force and displacement obtained from the tensile tests, the crack growth rate and stress ratio for each specimen were evaluated. The failure ratio, which allows the evaluation of shear, was also performed.

Planing hull vessel built with polymer matrix laminates and fiberglass reinforcements (GFRP) suffer structural damage due to the phenomenon of slamming during navigation, due to the impact of the boat hull on the free surface of the water at high speed. A modification in the manufacture of the laminates for these fast boats is proposed, consisting of the insertion of an additional layer of a hybrid material, formed by elastomer encapsulated in an ABS polymer cell. Using GFRP specimens made from pre-impregnated material and reproducing the characteristic impacts of slamming, it is possible to compare the modified material with the introduction of the viscoelastic layers with the response under the same conditions as the unmodified laminates. Additionally, the panels have been tested using impacts due to weight drop at different energies, which allow determining the material damage threshold as a function of the energy absorbed, and to establish a comparison with the GFRP panels modified by observation in fluorescent light. It is verified that the proposal to reduce the effect of these impacts on the generation of damage to the material and its progression throughout the service life of the vessel is effective.