March 2000, 32 pages
Building industry and design professionals are developing and improving efficient engineering methods to resolve unique housing structural design problems. One method uses concrete lintels in insulating concrete form (ICF) construction to transfer loads above window and door openings in walls.
Testing and Design of Lintels Using Insulating Concrete Forms summarizes the results from a study focusing on the structural performance of concrete lintels without shear reinforcement. The study, conducted by the NAHB (National Association of Home Builders) Research Center, Inc., investigated the need for shear reinforcement and developed an improved ICF lintel design methodology based on testing results. The report was developed as part of the Partnership for Advancing Technology in Housing (PATH).
Current design methods typically require vertical shear reinforcement as well as horizontal tensile reinforcing steel to support bending loads. However, in many residential and light construction situations, shear reinforcement may not be necessary to achieve adequate performance. Shear reinforcement is difficult to place in ICF forms, complicates the construction process, and creates difficulties in placing the concrete. This study evaluates the performance of simply supported concrete beams without shear reinforcement and with minimal tensile reinforcing steel subjected to third-point loading. The report also presents design recommendations for concrete lintel or beam design for each of the major ICF systems.
