Experimental investigation on in-plane shear behavior of E-glass fiber/epoxy laminated composites under different strain rates

Glass fiber reinforced polymer (GFRP) has been widely applied in buildings and bridges owing to its excellent material properties. The GFRP as a bearing load component in structures may be damaged, with an increasing threat from accidental impact. To understand the dynamic in-plane shear properties of GFRP is essential, which is a basis to design and evaluate structures. In this study, the ±45° specimens of GFRP laminated were tested to investigate the in-plane shear properties with the strain rate from quasi-static to 106 s⁻¹. The dynamic test was conducted by INSSTRON VHS and the stretch process was record by high-speed camera. The Digital Image Correlation (DIC) method was used to obtain strains of the specimens. And the field-emission scanning electron microscopy (SEM) technique was used to observe the fracture surface of the specimen. The results indicated that the failure mode, shear strength, failure strain, failure strain, absorbed energy and shear modules possessed strain rate effects. Furthermore, the empirical equations were proposed, which can be used to predict the dynamic increase factor at different loading rate.