Multi-Axial Composite Tube Test Method

Abstract

This paper discusses a new multi-axial 10.2-cm (4-in.) composite tube test method. This test method is capable of loading a 10.2 cm composite tube by internal pressure, torsion, and tension/compression. The method improves on an older biaxially loaded (internal pressure and axial load) tube design used extensively by Swanson and coworkers [1–5] to characterize the failure mode of fiber dominated pressure vessels. The 10.2 cm tube test method has been used successfully to test composite tubes by internal pressure combined with torsion and axial tension/compression. Tubes were tested at both ambient and hot/wet conditions. Tubes with various lay-ups, including, hoop and helical, and all helical configurations were tested. This paper discusses the development of the test method. This followed by the presentation of test data for ±25/90/±25 composite tube loaded in biaxially (internal pressure combined with axial load), pure torsion, and combined biaxial with torsion load. The test data offered are limited due to space restriction. Additional data will be presented in other ASTM publications.