DAMAGE ASSESSMENT OF TENSEGRITY STRUCTURES USING PIEZO TRANSDUCERS

This paper presents a low-cost experimental technique to carry out damage assessment of structures using dynamic strain measured by of surface-bonded piezo transducers. The technique is applied on a single module tensegrity structure, 1mx1m in size and then extended to a tensegrity grid structure, 2mx2m size, fabricated using galvanised iron (GI) pipes and mild steel cables. A single piezoelectric-ceramic (PZT) patch bonded on a strut measures the dynamic strain during an impact excitation of the structure. Damage is identified from the frequency response function (FRF) obtained after domain transformation of the PZT patch's response. For the grid structure, damage is localized using changes in the three natural frequencies observed experimentally and the corresponding mode shapes obtained numerically. The technique is found to be very expedient and at the same time cost effective, especially for preliminary damage detection in the structures.