Blast responses of panels made of a hybrid-fiber engineered cementitious composites
Explosive loading is one of the typical loadings encountered for defence and protective structures in military fields. Some strategic important civilian infrastructures such as government buildings, embassy buildings, bridges, nuclear plants might be the targets for a terrorist bomb attack. The application of construction materials with outstanding blast resistance capability is essential for defence or protective structures. Thus development of blast resistant construction and building material and understanding structural responses to blast loading are very important. In recent years, Zhang and her associates developed new hybrid-fiber ECCs reinforced with PVA fiber and steel fiber and studied the mechanical behaviour and impact resistance of ECC panels. It is found the material exhibits improved strength and very good strain capacity and good capability to resist impact via extensive experimental and numerical studies and numerical. But the blast resistance of the ECCs are not know yet and hitherto no research on the blast response of ECC material or ECC panels have been reported.
In this research the structural behaviour of ECC panels under blast loading is investigated. 3-D numerical modelling using LS-DYNA, which is an explicitly dynamic finite element software package will be employed to investigate the structural behaviour of the ECC panels under blast loading. To compare the blast resistance, the structural behaviour of a conventional steel rebar reinforced concrete panel is also studied. The success in the simulation of the structural responses of concrete structures using commercial FE tool is highly dependent on the constitutive models of the material and the equation of state. Thus the research will focus on the development of dynamic material models for the ECC under tension and compression with strain rate effect considered. Experimental studies will also be conducted to obtain the physical structural responses of the panels under blast loading.
Through this research it is expected that efficient constitutive model under blast loading with strain rate effect for ECCs and modelling and analysis techniques for predicting the blast responses of ECC panels will be developed. The outcome of this project will largely promote and enhance the applications of the new ECC composites in defensive and safety-sensitive structures and will improve structural safety of these kinds of structures.