Damage Detection by Load Path Changes in Reinforced Composite Panels Using Local FBGS and Distributed Sensing
A SHM technique based on the load path changes has been used to identify debondings in two blades st iffened space grade composite panels. These panels have been instrumented with Fiber Bragg Grat ings Sensors, FBGS. The egress of the optical fiber from these panels was made in one panel with pig tails and in the other with embedded optical connectors. Additionally to the local FBGSs, distributed sensors based on the Rayleigh backscattering ffect have been embedded in the skin of the second panel. This se nsor technique assesses the st rains along the entire optical fiber length not only in the stiffeners but also in the skin of the panel. Both techniques have been compared during compression tests of the panels and their ability to detect damage has been evaluated. Very good agreement has been obtained b tween strain meas ures of local and distributed sensing. The distributed sensing technique enables to asses the load path changes very detailed in a global strain ma pping of the entire structure, identifying stiffener breakage, skin/stiffener debondi ng and buckling effects. The distributed sensing has demonstrated its high potential for damage detection of stiffened panels made by fiber placement technology usin g the load path change assessment. _____________ INTA, Area de Materiales Compuestos; Crta. Ajalvir, P.K.4, 28850 Torrejon de Ardoz (Madrid) Spain, frovelm@inta.es ASTRIUMEADS Casa Espacio, Avd. de Aragon 404, 28022 Madrid, Spain ETSI Aeronauticos, UPM, Pza. Cardenal Cisneros 3, 28040 Madrid, Spain Escuela Universitaria Politecnica La almunia de Dona Godina C\mayor sn la almunia de dona gomina, 50100 Zaragoza (Spain) 6th European Workshop on Structural Health Monitoring Fr.2.B.2 Licence: http:/creativecommons.org/licenses/by nd/3.0 1 M or e in fo a bo ut th is a rt ic le ht tp w w w .n dt .n et id 14 14 7