Blast enhanced façade design by means of an optimal balance between security and sustainability

Abstract

The major objective of this paper is to show that glazed curtain wall has a surprising potential for blast enhancement. However, often this potential is partially lost because of inaccurate and only presumed safe side approach. Indeed, in curtain wall it is much important to assess properly the beneficial effect of the deformable supports, framing and possibly brackets, on the glazing response under blast wave effects. Only in this way a true balanced design approach can be carried out and the protective requirement can be integrated into the façade design by preserving the architectural requirements, comfort, classical energy efficiency requirements and novel demand for sustainability. On the other side the large variability of materials and component behaviour under nonlinear range and the uncertainties related to the blast threat recommend a flexible calculation tool, which must be coupled with a sensitivity analysis on the most relevant inputs. For this reason, a Multi Degree of Freedom approach shows several advantages with respect to the Explicit Dynamic Finite Element Analysis, considering also the large number of geometry, component design and blast load variations are existing in a typical application of the protection on a high rise building. The impact of the calculation method is demonstrated by means of a comparative exercise and by means of real case applications.