Shake Table
SIPs really are a strong structural panel building component found in residential homes and commercial buildings for that walls, roofs and floors. SIPs have a good reputation for performance in seismic events. Specifically, numerous SIP structures were located near to the epicenter with the magnitude 6.9 earthquake that struck Kobe, Japan in 1995. Overview of these structures after the earthquake established that the inherent performance of SIPs in seismic events is exceptional.
SIPs develop their shear strength from the use of outer facings of 7/16" OSB manufactured in conformance with all the PS2 standard for sheathing. Each SIP wall panel is linked to base plates, top plates, and vertical boundary members with fasteners, typically 8d nails. The 8d nails give the transfer of the shear loads from the OSB facings towards the wood plating materials as the bond with the OSB for the EPS core provide resistance for the OSB from buckling. This performance is analogous to conventionally built OSB sheathed shear walls the location where the OSB provides shear resistance by using fasteners to transfer shear loads for the framing members.
SIPs have been evaluated side-by-side with OSB sheathed conventional walls. Testing has been conducted by the leader in the development of shear wall design data for light frame walls, APA - The Engineered Wood Association. Testing contains building conventional OSB sheathed 2X shear walls and comparing the performance to Structural Insulated Panels.
Testing was conducted following a seismic test protocol put together by the Structural Engineering Association of Southern California (SEAOSC). The test contains imposing a simulated seismic event with a shear wall and recording the response. The exam protocol contains 72 cycles of loading for that shear wall. The resulting loads and deflection for that conventional shear wall as well as the SIP wall were nearly identical.
Shake Table
It is recommended that SIPs act like conventional light frame shear walls with OSB sheathing for performance in seismic events with proper engineering of connections and load transfer.