STRUCTURAL PERFORMANCE OF COMPOSITE LAMINATES WITH EMBEDDED FIBER OPTIC SENSOR UNDER TENSION AND COMPRESSION LOADS

A parametric study on effect of embedded fiber optic sensor (FOS) in composite laminates under tension and compression loads was conducted. Inclination of FOS with respect to reinforcing fiber (loading direction) was varied from 0 to 90 degrees and the laminate thickness varied from 8 to 20 plies. Embedding FOS caused resin pockets and disturbance of reinforcing fibers. The disturbance angle varied from 6.8 to 7.5 degrees and the resin pocket area varied from 7.1 to 9.7 times the area of the sensor. These two types of defects caused the failure initiation to be by fiber splitting at one end of the resin pocket. The defects had no loss of tensile modulus and about 10% loss of tensile strength while compression strength reduction was as much as 40%.