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A number of studies have been performed to understand the lateral load carrying capacity of wood frame shear walls. The existing studies, however, have been primarily focused on the intact shear walls, disregarding the possibility of capacity loss due to prior extreme loading events. During windstorms, in particular, windborne debris is the leading cause of damage and destruction. While the impact force induced by windborne debris can directly damage a shear wall, the consequences can become disastrous, as the prior damage adversely affects the in-plane lateral load carrying capacity of the shear wall. This critical aspect motivated the current study to investigate the impact and post-impact performance of wood frame shear walls. For this purpose, a high-fidelity computational framework capable of characterizing both types of damage is developed. Further to providing an in-depth understanding of the process of damage formation and propagation, this study examines how a range of impact scenarios and wall design factors influence the extent of damage that the wood frame shear walls experience in a windstorm. The outcome of this study is then employed to introduce a capacity loss index for the multi-hazard design and assessment of wood frame (and other similar) shear walls in the regions prone to severe windstorms.
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Vulnerability assessment of Structural Insulated Panels with metal skins subjected to windborne debris impact
Structural Insulated Panels (SIPs), which consist of a composite of an insulating polymer foam sandwiched between two layers of structural skins, are widely used in residential and commercial buildings. Such panels, in the regions prone to hurricanes and tornadoes, are often exposed to the risk of windborne debris impact. Despite the consequences associated with damage to SIPs, the studies on their perforation resistance and design variables have been rather limited. To address this gap, the current study develops a computational framework to assess the vulnerability of the SIPs of various configurations subjected to a range of windborne debris impact scenarios. For this purpose, impact simulations are conducted to quantify the response and evaluate the extent of damage to the SIPs. The study is further extended to evaluate the effect of various structural details and material properties on the perforation resistance of the SIPs. Based on the simulation results, a set of vulnerability curves are developed for the first time to capture the risk of failure of the SIPs under the windborne debris hazard. This is expected to improve the design of this important category of wall panels, especially to ensure their safety and performance during severe windstorms.
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- PAR ID:
- 10176379
- Date Published:
- Journal Name:
- Composites
- ISSN:
- 1359-8368
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/https://doi.org/10.1016/j.compositesb.2020.108163
