Equivalent-Design Crack Model for Structural Glass Elements

Analytical determination of safety in glass structures often uses oversimplified resistance criteria or fully probabilistic models which require special software to numerically solve the complex equations. Due to computation cost and remaining uncertainty in these different analytical methods, engineers are often required to perform expensive experimental tests to reliably determine glass-structure safety. As a compromise between the need to accurately model the complex mechanical behavior of glass failure and the need to reduce analytical complexity in calculations, this paper proposes a simple semiprobabilistic failure prediction model for glass structures, called the equivalent-design crack model (EDCM). The EDCM is defined using the basis of linear elastic-fracture mechanics, characterized by a mathematical expression that depends on the probability of failure and the level of surface damage. The proposed model considers the influence of surface area, load time-history and complex stress fields within the structural elements. Experimental results from four-point bending and coaxial double-ring tests show good agreement with analytical results using the proposed EDCM method. Application ofthe EDCM in structural design is also presented.