In-Plane Shear Resistance of Insulating Concrete Form Walls

Authors: NAHB Research Center Inc.    

The efficient use of shear walls in residential construction subjected to wind and seismic loading is of great interest to designers and builders of homes in high hazard areas of the United States. Shear walls are the primary lateral force resisting system in residential construction. There has been considerable research aimed at optimizing the design of light-framed shear walls (wood and cold-formed steel) in recent years. For relatively new types of wall systems, such as Insulating Concrete Form (ICF) wall construction, the technical information available is limited. There is a need to confirm or improve the use of traditional concrete shear wall design methods particularly in the context of ICF systems and residential construction practices. Thus, inefficiencies that result in conservative (uneconomical) or unconservative (unsafe) applications may be avoided.

A research program was initiated at the NAHB Research Center to study the structural performance of ICF walls when subjected to in-plane shear loading. An experimental study was designed to determine the influence of the following factors on the in-plane shear strength of ICF walls: (1) height-to-length aspect ratio of shear wall segments, (2) openings for windows and doors, and (3) the current minimal reinforcement details provided by the Prescriptive Method for Insulating Concrete Forms in Residential Construction (Prescriptive Method) [1]. The main goal of this study was to confirm and improve methods of evaluating the in-plane shear capacity of ICF walls. This information is intended to improve the shear wall design and construction guidance found in the Prescriptive Method [1] and the International Residential Code [2].

Publication Categories: Publications     Housing Production and Technology     Building Materials     Concrete