Modeling Concrete Masonry Walls Subjected to Explosive Loads

Abstract

Concrete masonry unit walls subjected to blast pressure were analyzed with the finite element method, with the goal of developing a computationally-efficient and accurate model. Wall behavior can be grouped into three modes of failure, which correspond to three ranges of blast pressures. Computational results were compared to high-speed video images and debris velocities obtained from experimental data. A parametric analysis was conducted to determine the sensitivity of computed results to critical modeling values. It was found that the model has the ability to replicate experimental results with good agreement. However, it was also found that, without knowledge of actual material properties of the specific wall to be modeled, computational results are not reliable predictors of wall behavior.

Reliability of Concrete Masonry Unit Walls Subjected to Explosive Loads

“…Eamon et al (2004) developed a numerical model that provided good comparison to the existing experimental data, in terms of both wall failure and debris velocity. The models were solved with a readily available commercial code DYNA3D (LLNL 1999), and are used for this study.…”

“…The models were solved with a readily available commercial code DYNA3D (LLNL 1999), and are used for this study. Full details of the models and comparisons to the experimental results are given elsewhere (Eamon et al 2004). A brief summary of the structural model is presented here, while a description of the blast loads is provided in the section…”

“…Walls were thus modeled similarly to a plane-strain model in which length of the wall is represented by a unit-length stack of CMU blocks, as shown in Figure 1. Full details of the experimental results are given elsewhere (Dennis et al 2002;Eamon et al 2004). In general, however, the test walls had the geometry described above, were constrained at the top and bottom with side edges free (representing an in-fill wall between building columns) and exposed to a blast load with parameters described later.…”

“…Material properties were taken from the experimental data and existing literature (Eamon et al 2004). …”

“…These results were subsequently used to develop numerical models for future studies of façade performance evaluation and retrofit options (Eamon et al 2004). …”