239. HEALTH MONITORING OF INTERLAMINAR DELAMINATION IN COMPOSITES
Name: Eduardo Velazquez
Grad Year: 2011
Advanced laminated composite have superior in-plane strength. However, their out-of-plane strength is usually one or two orders of magnitude lower due to the fact that it is a matrix-driven as opposed to a fiber-driven property. In order to avoid failures due to interlaminar damage without using high margins of safety, a Structural Health Monitoring (SHM) system can be used. While extensive literature exists on SHM systems for fiber-driven damage and bond-line damage, there is no mention of an SHM system that specifically addresses this type of matrix-driven damage. The proposed SHM system spans the acquisition, location, and reconstruction of Acoustic Emission (AE) damage signals. An algorithm is presented to calculate the most likely location of AE damage signals in a laminated composite structure. Also, a procedure is presented to decide the damage type and reconstruct the loading source time series for a recorded damage signal from a multi-channel system. The SHM algorithm was experimentally validated using a semi-elliptic laminated composite specimen to induce interlaminar delamination at a prescribed thickness location and with an impacted composite plate to induce multi-mode damage.