Improving Strain Field Measurements for Textile Composites

Models for Textile Composites Forming

INTRODUCTION Drape of dry fabrics or prepregs was recognised as an important feature in composites forming operations from the start. In the 1950s the first mathematical models were developed based on purely kinematic arguments. The assumption of zero fibre strains and trellis deformations led to the socalled fishnet approach. Typically, these methods require certain arbitrary constraints to re...

Strain Gage Measurements on Plastics and Composites

The bonded resistance strain gage, which is central to the topics treated here, was invented in the late 1930's and is now at about the mid-century mark in its career. During the first fifty years of its existence, the strain gage has been applied to virtually every known load-bearing material – ranging from asphalt to zirconium, and missing few, if any, of the letters in between. Whether the m...

Diagnosis of Delaminated Composites Using Post-processed Strain Measurements under Impact Loading

Potentially having a destructive influence on the mechanical properties of composite laminates, the invisible phenomenon of delamination frequently occurs under impact loading. In the present study, simulating the performance of long-gauge fiber Bragg grating sensors, impact-induced average strains within laminated composites are utilized to develop a delamination identification technique. Firs...

Handbook of Analytical Methods for Textile Composites

Sensor for Measuring Strain in Textile

In this paper a stain sensor to measure large strain (80%) in textiles is presented. It consists of a mixture of 50wt-% thermoplastic elastomer (TPE) and 50wt-% carbon black particles and is fiber-shaped with a diameter of 0.315mm. The attachment of the sensor to the textile is realized using a silicone film. This sensor configuration was characterized using a strain tester and measuring the re...