Two failure mechanisms are considered for the roof envelop, namely; failure of roof cladding, and purlin failure.
However, the levels of possible damages at community level due to the pull-through failures of roof battens are still unknown.
Failures of roofing systems occur due to high local suctions on tiles or shingles, or because of a different failure mechanism triggered by high local wind velocities near the roof surface.
High wind uplift loads acting on the light gauge steel roofing systems during tropical cyclones and storms frequently cause premature failures of roof connections, which lead to extensive damage to roofing systems.
Then it provides the details of a numerical parametric study conducted to study the pull-through failures of roof battens in relation to influential parameters such as batten geometry and screw fastener head sizes.
Since an acceptable small scale connection test method is not available for fatigue pull-through failures of roof battens, various types of small scale connection tests were initially examined to propose the most suitable test method.
Therefore a detailed experimental study consisting of both small scale and full scale tests was undertaken to investigate the pull-through failures of roof battens under wind uplift loading in relation to many critical parameters such as screw fastener tightening, roof batten geometry, batten thickness, steel grade, screw fastener head size and screw fastener location.
In fact, failure of overlying roof strata is mainly governed by the geology and strength of the strata.
Less common perhaps, but usually catastrophic, is the failure of the roof-to-wall connections in these structures.
According to the layered Hoek-Brown rock masses with different characteristics, a continuous failure mechanism of roof collapse in the deep cavities is derived by using upper bound solutions.
The "excessive pounding" could cause "catastrophic failure" of already-compromised roofs, said Steven Desilets, the city's building commissioner.
