Compression Strength of Composites Containing Embedded Sensors or Actuators

A theoretical linear-elastic model is used to study the effect of embedded sensors and actuators on a composite's compression strength. An existing analytical model is employed to predict the local undulations in the plies which result from the presence of the embedded devices. Using these results in conjunction with a micromechanical model for compression strength, prediction, are made for the reduction in this property due to sensors or actuators. Comparisons are made with ex penmental data for graphite epoxy systems, and the model is shown to accurately predict the trends in such data. Parametric studies are performed to investigate the effect of embedded semor/actuator diameter, laminate thickness, laminate stiffness, and laminate shear strength on the compression strength of composites containing these embedded sensors/actuators. It is shown that degradations in a composite's compression strength is as Severe for sensors/actuators embedded at 30° as those embedded at 90° to the structural fiber,