Carbon fiber reinforced plastics (CFRP) are widely used in lightweight marine structures due to their high strength and superior fatigue behaviour. In this paper, we will present an innovative methodology for simultaneous load and structural monitoring of a CFRP rudder stock as part of a big commercial vessel. Experimental results are presented here from a quasi-static tensile test in which the load monitoring is performed using embedded strain sensors. Structural monitoring is based on high-frequency electromechanical impedance (EMI) spectroscopy combined with dedicated signal processing and surface mounted piezoelectric transducers. We have achieved the following results: (i) the demonstration of a hybrid monitoring system including load and structural monitoring, (ii) successful embedding of strain gauges during composite manufacturing of the CFRP rudder stock (iii) development of instrumentation hardware for multichannel EMI measurements, and, (iv) successful damage detection by means of EMI spectroscopy in thick CFRP rudder stock samples exploiting strain data.
More information:
Neuschwander, K.; Moll, J. ; Memmolo, V.; Schmidt, M. & Bücker, M., Simultaneous Load and Structural Monitoring of a Carbon Fiber Rudder Stock: Results from a Quasi-Static Tensile Test, Journal of Intelligent Materials Systems and Structures, 2018 (accepted in September 2018)