Influence of Negative Phase Loading on Cable Net Facade Response

Abstract

The behavior of cable net facades subjected to blast loads differs significantly from the behavior of stiffer structures, such as post-and-rail facades or classical concrete or steel structures. The low eigenfrequencies and the relatively small specific weight of cable net facades cause larger deformations and higher structural velocities. The negative pressure phase of a blast load can especially have a significant effect on the structural response. The negative phase can either increase or decrease the deflections. Nevertheless, the United States and international threat levels according to the United States General Services Administration and the ISO neglect the negative phase of blast loads. In the present investigation, a comparison and assessment was done to present the differences between the standard blast load model, that is, a triangular-shaped blast load neglecting the negative phase, and the exponentially decaying Friedlander blast load model, which takes the negative phase into account. Then, the implications for the structural response are analyzed, and conclusions for the protective design of cable net facades are presented.