Direct Fastening Technical Guide , Edition 24
3.2.8.3.2 General discussion
According to the International Building Code ( IBC ), a shear wall is a lateral force resisting structural system that provides resistance to wind , seismic and other lateral forces and provides stability to the overall structure . It is a structural assembly that can be modeled as a vertical cantilevered beam . A shear wall may be constructed using several methods . One common way of building shear walls is using CFS framing members covered with wood structural panels . An example of a CFS framed shear wall assembly is shown in Figure 3 . Wood structural panels are attached to the CFS framing members with fastening systems that have been properly evaluated for this application .
Design of shear walls has traditionally been done using the available tables in AISI S240 , which are based on full-scale shear wall testing . ICC-ES and the IBC allow for development of an analytical method based on the principles of mechanics to be used for the design of CFS framed wood structural panel sheathed shear walls . ICC-ES recognizes full-scale test analysis as an acceptable design approach in AC230 Acceptance Criteria for Power-Driven Pins for Shear Wall Assemblies with Cold-Formed Steel Framing and Wood Structural Panels . Shear wall analytical models are based on fastener shear connection data using the following parameters :
1 . CFS member type and thickness 2 . Wood structural panel type and thickness 3 . Fastener spacing in the field and along the perimeter
3.2.8.3.3 Fastener test programs
Many ICC-ES small element connection tests and full-scale static and cyclic / simulated seismic load test programs have been conducted using Hilti X-PN 37 MX fasteners to determine the shear wall system performance .
1 . Small element connection tests
Small element connection tests are conducted to determine fastener transverse strength ( pullout or pull-through ) and lateral strength ( shear ) with structural wood panels and CFS sections representative of typical shear wall construction . The data is analyzed and used in a predictive model to calculate the performance of the larger shear wall assemblies . These tests are conducted in accordance with following standards and shown in Figures 4 and 5 .
• ICC-ES AC230 Acceptance Criteria for Power-Driven Pins for Shear Wall Assemblies with Cold-Formed Steel Framing and Wood Structural Panels
• ASTM E1190 Standard Test Methods for Strength of Power-Actuated Fasteners Installed in Structural Members
• ASTM D1761 Standard Test Methods for Mechanical Fasteners in Wood
Figure 4 : Small element transverse strength ( pullout , pull-through ) tests
Figure 5 : Small element lateral strength ( shear ) tests
51