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Topic

Performance of high-capacity light wood-frame shear walls with multiple rows of nails: experimental and numerical study

Department of Civil Engineering

Date & location

• Tuesday, October 28, 2025

• 10:00 A.M.

• Virtual Defence

Reviewers

Supervisory Committee

• Dr. Lina Zhou, Department of Civil Engineering, ӣ��Ӱ�� (Co-Supervisor)

• Dr. Chun Ni, Department of Civil Engineering, UVic (Co-Supervisor)

• Dr. Phalguni Mukhopadhyaya, Department of Civil Engineering, UVic (Member)

• Dr.  Minghao Li, Department of Wood Science, University of British Columbia (Outside Member) 

External Examiner

• Dr. Matiyas Bezabeh, Department of Civil Engineering, McGill University 

Chair of Oral Examination

• Dr. Sandra Marquis, School of Public Health and Social Policy, UVic 

Abstract

With the increase of building height limit for light wood-frame construction up to six stories and the increase of seismic response spectra in national building code of Canada, stronger shear wall systems have been facing higher demands, especially for mid-rise wood-frame buildings located in high seismic zones. The ӣ��Ӱ�� and FPInnovations have jointly developed a new high-capacity shear wall system with two or three rows of nails on sheathing edges. A three-year test program was carried out in 2020-2022, with a total of 30 shear wall specimens covering a range of configurations, including different sheathing thicknesses, nail sizes and spacings, stud dimensions and stud numbers.

In the first part of this study, test results from 2021 and 2022 were presented. It was found that the high capacity shear wall systems can achieve lateral load resistance proportional to the number of rows of nails on sheathing edges. Due to the brittle failure modes observed in high-capacity shear walls that are not common in regular shear walls with only one row of nails on sheathing edges, much lower design resistance has to be assigned for high-capacity shear walls to meet the ductility requirements in concordance with ASTM D7989. 

In the second part of this study, the brittle failure modes observed in high-capacity walls were summarized and analyzed, including stud separation from plates, plate and stud splitting, sheathing rupture, and sheathing buckling. Methods of preventing these failure modes were proposed and discussed, such as installing steel angles to prevent stud separation from top or bottom plates, installing steel plate washers at locations of hold-downs to prevent bottom plate splitting, and limiting one row of nails on each framing member to prevent stud and plate splitting. 

In the third part of this study, detailed 3D numerical models of high-capacity shear walls with multiple rows of nails were developed using ABAQUS. The models were first verified by test results from this program, showing good agreement in load-displacement response. The numerical models were also capable of mimicking some of the brittle failure modes observed in high-capacity wall tests, such as stud separation from top and bottom plates. Then, a parametric study based on the verified shear wall model was carried out, considering different wall configurations that were not included in the previous test programs, i.e., high-capacity shear walls with different heights, lengths, stud sizes, sheathing arrangements, hold-down types, and with and without vertical loads. Results showed that, similar to regular shear walls, the lateral load capacity of high-capacity shear walls is proportional to the wall length, while the stiffness decreases as wall height increases. Stud sizes had no significant effect on wall performance, while sheathing panel size played an important role in terms of shear wall resistance and deformability. Increasing vertical load significantly improves the lateral performance of high-capacity shear walls with no hold-downs. However, the influence of vertical load is negligible for walls with hold-downs.