Author: Donald W. OplingerPublisher:
ISBN:
Category : Shear (Mechanics)
Languages : en
Pages : 26
Book Description
This report covers stress analysis and experimental studies of four types of tension specimens designed for testing composite materials. Two ASTM specimen types (D3039 tab-ended and D638 dogbone) are considered, along with the bowtie (flat bar with linear taper) design developed by Grumman and a streamline design developed at AMMRC. Stress analyses of the first three types show them to be subjected to high shear stresses and tensile stress concentrations which tend to degrade their performance. Experimental studies generally tended to confirm that failures initiated where the stress peaks were predicted, and suggest that elimination of such peaks would lead to a better-performing tension specimen. Stress analysis of the AMMRC streamline design showed how shear stress levels and indicated that the design is free of tensile stress concentrations. Results of efforts aimed at experimental evaluation of the streamline specimen indicate that it has much promise as an improved design for tension testing, both under monotonic and cyclic loading. (Author).