SDOF response model parameters from dynamic blast loading experiments

In this paper, two minimization problems are presented that determine parameters for best practice single degree of freedom (SDOF) models, based on the blast response of structural members. The inputs for the model are dynamic experimental data as obtained from pressure and laser deflection measurements. The first approach compares model and experimental deflection and minimizes the differences between the two. Within this approach, a method is introduced to determine the best parameters of typical structural resistance functions for SDOF models. Examples for the determination of up to three parameters are given. The second approach uses a set of basic functions in terms of deflection and velocity to describe the resistance function as a linear combination of functions. Using experimental data, a matrix equation is obtained from the single degree of freedom force equation. Taking advantage of the minimization conditions, a second matrix equation is derived, then numerically inverted and solved for the response basis function expansion parameters. In a systematic way the response function may be improved, e.g. by adding more terms to polynomial basis functions. Both procedures determine SDOF and in particular response function parameters from dynamic data and also indicate whether they are well selected. Combining parameter data of multiple events and failure criteria, the overall model and failure behavior are determined in a P-I diagram for the example of a standardized laminated glass pane. (C) 2009 Elsevier Ltd. All rights reserved