Stefano Vozzella, Claudio Boni, Roberta Massabò and
Gianni Royer-Carfagni
Vol. 20 (2025), No. 3, 289–313
DOI: 10.2140/jomms.2025.20.289
Abstract
Most standards reduce the design strength of glass through a modification coefficient
that accounts for static fatigue caused by subcritical propagation of surface cracks.
For wind pressures on glass plates, the coefficient is derived assuming nominal
durations of maximum wind gusts or cumulative winds, which are defined
based on tradition and practice. Here we derive closed-form expressions
for the modification coefficient using a fracture mechanics approach which
incorporates the time histories of wind velocity or their probabilistic distributions.
The coefficient depends on the duration of the action and becomes constant
for typical design lives. A consistent nominal duration is then defined by
referring to a wind with fixed reference velocity which produces the same
damage of the actual action. The approach, applicable to the European
context, has been applied to data recorded in Italy. The results are compared
with prescriptions from various standards showing that they are in general
non-conservative.