Dynamic behaviour of unstiffened stainless steel profiled barrier blast walls

Performing optimum design, reliable assessment or suitable verification for stainless steel profiled barrier blast wall structures requires dealing with various challenges, stemming from the associated uncertainties in material properties, fabrication, installation, and more importantly variations in the blast load characteristics. In the analysis, assessment, and design of these blast walls, one of the key areas to be appreciated and understood is the dynamic response of these structures. This paper presents a methodology developed for identifying the predominant structural behaviour and characteristics of profiled barrier blast wall structures, using a probabilistic approach. Twenty parametric base models are developed using Ansys and by implementing a Latin Hypercube Sampling (LHS) approach, the section properties of the models are represented in terms of probability distributions. A number of models are generated stochastically and modal analyses performed to identify the dynamic sensitivity of these models. The corresponding response classification of these structures is evaluated from the load duration and natural periods of the structures. The results of the study confirm that structural response, for the wide range of profiled blast walls analysed, is mainly quasi-staticor static, as opposed to dynamic. In fact, dynamic effects are negligible for unstiffened profiled barrier blast walls and structural responses in most cases can be estimated on a static or quasi-static basis. This conclusion would help a competent design engineer to consider a proper dynamic load factor at an early stage of the design, without involving complex advanced nonlinear dynamic analyses.