NEHRP Clearinghouse
- Title
- The Use of Structural Foams to Improve Earthquake Resistance of Buildings.
- File
- PB287121.pdf
- Author(s)
- Gabrielsen, B. L.; Lindskog, R.
- Source
- National Science Foundation, Washington, DC. Applied Science and Research Applications., June 1978, 312 p.
- Identifying Number(s)
- 7732
- Abstract
- The objective of this program was to develop and test the feasibility of using polyurethane foam to increase the shear capacity of timber stud walls, timber joist floors, and ceilings and foundation to floor connections. The specific tasks were to develop foam placement techniques, document increases in strength due to foam, and determine the feasibility of using these techniques in new construction. The results of this largely experimental program indicated that substantial increases in shear strength were achieved in walls, floors, and ceiling systems. For example, a typical sheathed roof or floor system by current code would have no seismic shear resistance. It was shown experimentally, however, that a floor system (2 x 8 joist, 1 x 8 sheathing) when foamed developed a 1650 lb/ft shear enhancement and 2450 lb/ft composite shear capacity. Also, from an energy standpoint the energy absorbed by a foamed panel was approximately 10 times that of an unfoamed panel. Tests of floor-to-foundation connections upgraded by foam also indicate substantial increases.
- Keywords
- Ceilings (Architecture); Energy absorption; Earthquake resistant structures; Roofs; Polyurethane resins; Walls; Buildings; Earthquake engineering; Foam; Structural analysis