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Tear propagation is a typical breakage modality of fabric laminates. In this paper, analysis methods and their empirical formulas about tear propagation of a kind of fabric laminate which is used in high altitude lighter-than-air vehicle (LTA) is studied. The methods include Griffith’s energy balance method, Thiele’s empirical formula method, Stress field consideration method and critical stress intensity factor method. Testing about tear propagation strength in biaxial stress is done by a tailor-made testing machine to study on the methods. And then a comparison is drawn between these formulas and results of the experimentation. Subsequently, advantages and disadvantages of these formulas and their scope of application are concluded. While by using the empirical formulas, the analysis of tear propagation of different incision shapes is given. It is useful for the further study on different fabric laminates.

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Inflatable space vehicle (ISV) has a variety of advantages of light mass, volume changeability and low cost, and becomes the hotspot in space vehicle research recently. But most researchers concentrate their efforts on applications of ISV in their dedicated domains, and the holistic viewpoint of ISV is indistinct. In this paper, the new developing space vehicle, ISV is classified into flatness, lenticula, sphere and cabin in brief due to its different structures and applications. Each type owns its special materials for folding, inflation-deployment, rigidization and resistibility in the space rigorous environment. Materials utilized in typical ISV are summarized subsequently, which can be sorted by polymer films, flexible rigidizable composites and multiple-layer laminates. Finally, the properties of ISV materials including environment endurance, mechanics, fabrication technologies and special functions are concluded, which is useful in material design and optimization.

Regarding the liquid-air hammer rod as the research object, the equivalent stress contour of the hammer rod has been obtained through transient dynamics simulation analysis of the hammer rod impact process by using finite element method. This paper has studied node rate response in different positions of the hammer rod to provide evidence for structure design of this kind of impact members.