Practical Modeling for Wind Load Paths in a Realistic Light-Frame Wood House: Fid-Bau Portal

Practical Modeling for Wind Load Paths in a Realistic Light-Frame Wood House

Pfretzschner, Kathryn S. / Gupta, Rakesh / Miller, Thomas H.

Abstract

The objective of this study was to develop and validate practical modeling methods for investigating load paths and system behavior in a realistic light-frame wood structure. The modeling methods were validated against full-scale tests on subassemblies and an L-shaped house. The model of the L-shaped house was then modified and used to investigate the effects of reentrant corners, wall openings, and gable-end retrofits on system behavior and load paths. Results showed that the effects of adding reentrant corners and wall openings on uplift load distributions were dependent on the orientation of the trusses with respect to the walls. Openings added to walls parallel to the trusses have the least effect on loads carried by the remaining walls in the building. Varying reentrant corner dimensions under design wind loads caused increasing degrees of torsion throughout the house depending on the relative location and stiffness of the in-plane walls (parallel to the wind loads) and the assumed direction of the wind loads. Balancing the stiffness of the walls on either side of the house with the largest reentrant corner helped to decrease torsion in the structure under lateral loads. Finally, although previous full-scale tests on gable-end sections verified the effectiveness of the gable-end retrofit that was recently adopted into recent Florida building code, questions remained about the effects of the retrofit on torsion in a full building. The current study found that adding the gable-end retrofits to the L-shaped house did not cause additional torsion.