Analysis of influence of imperfections on stiffness of fully anchored light-frame timber shear walls: elastic model
2009 (English)In: Materials and Structures, ISSN 1359-5997, E-ISSN 1871-6873, Vol. 42, no 3, 321-337 p.Article in journal (Refereed) PublishedText
In order to stabilize light-frame timber buildings against horizontal loads, the diaphragm or in-plane action of roofs, floors and walls is often used. This paper deals with the influence of imperfections such as gaps and uplift on the horizontal displacement of fully anchored shear walls. The significance of analyzing the effects of imperfections is evident when evaluating the stiffness of shear walls; tests of walls show that the horizontal displacement is underestimated in calculations using the stiffness of sheathing-to-framing joints as obtained from experiments. Also, in real structures where hold-downs are used according to the elastic design method, the influence of gaps and uplift should be included in order to obtain realistic displacements in the serviceability limit state. A new elastic model for the analysis, based on linear elastic behaviour of the mechanical sheathing-to-framing joints, is presented and the equations for the stiffness and the deflection versus the number of segments in the wall are derived. The fully anchored condition for the shear walls are modelled by applying a diagonal load to the wall. Three types of imperfections are evaluated: gaps at all studs, a gap only at the trailing stud, and gaps at all studs, except at the trailing stud. It is shown that the effect of imperfections on the stiffness of the wall in the initial stage is considerable. Depending on the distribution of the gaps and the number of segments included in the shear wall, the displacement of the shear wall is increased several times compared to that of a fully anchored shear wall with no gaps; e.g. for a single segment wall more than three times. However, for walls with more than six to ten segments, the effect of imperfections can be neglected. Finally, the theoretical model is experimentally verified.
Place, publisher, year, edition, pages
Springer Netherlands, 2009. Vol. 42, no 3, 321-337 p.
Shear walls, Imperfections, Gaps, Uplift, Elastic model, Full anchorage, Stiffness, Shear wall displacement
Materials Engineering Building Technologies
IdentifiersURN: urn:nbn:se:umu:diva-116015DOI: 10.1617/s11527-008-9458-7ISI: 000264103200003OAI: oai:DiVA.org:umu-116015DiVA: diva2:905430