A statistical volume element-based procedure for the prediction of the mechanical and electrical response of an epoxy-PZT self-sensing layer for application in composite laminates

Structural Health Monitoring (SHM) techniques are being developed to continuously oversee defects in composite structures. Within this context, research is focusing on the development of new types of sensors with high sensitivity and proper integration in the laminate. In this work, the mechanical and electrical properties of a recently developed piezoelectric composite material made of a Lead Zirconate Titanate (PZT) powder embedded in an epoxy matrix are evaluated with finite element simulations of plane strain Statistical Volume Elements (SVEs). The homogenized properties are then implemented in a second finite element model of a composite specimen with the embedded self-sensing material and loaded in compression. The electrical sensitivity is evaluated as a function of the distance between the signal electrodes. The results show that the finite element models with the homogenized properties have decreasing sensitivity with increasing electrodes distance, in agreement with the experimental results from another work, in which Glass Fiber Reinforced Polymer (GFRP) laminates with the embedded piezoelectric composite are loaded in compression and tested for output signal. • The properties of a composite lead-zirconate-titanate powder/epoxy piezoelectric material are evaluated via finite element modeling of a statistical volume element. • This material is promising in the context of structural health monitoring, given its flawless integration in composite laminates. • The homogenized properties are the input for a digital twin of a compression loaded sample with the novel piezoelectric material. • The comparison between the digital twin and the experiments shows good accordance in terms of electrical sensitivity. • The proposed methodology is viable to predict the mechanical and electrical properties of any piezoelectric composite with lead-zirconate-titanate powder reinforcement, opening new promising scenarios for the design of self-sensing composite laminates or bonded joints with an excellent integration between the sensor and the host structure.