- Author
- Carlson, C. C.
- Title
- Fire Resistance of Prestressed Concrete Beams. Study A: Influence of Thickness of Concrete Covering Over Prestressing Steel Strand.
- Coporate
- Portland Cement Assoc., Skokie, IL
- Report
- Bulletin 147, July 1962, 45 p.
- Keywords
- prestressed concretes | beams | thickness | fire tests
- Abstract
- The rapid growth of the precasting industry in the United States during the past 10 years and the attending wider use of precast, prestressed concrete structural shapes for building construction has created a nned for basic design information on the fire resistance of prestressed concrete. This paper is the first of a series of reports which have been planned as contributions to this need. The results of standard ASTM fire tests conducted on 18 pretensioned, prestressed, concrete "I" beams of 20-ft span are analyzed and discussed. the principal variable of the study was concrete covering thickness over the prestressing steel. The influence of concrete coverings in 1-, 2- and 3-inch thicknesses in normal weight and expanded shale lightweight concretes were investigated. Various other factors affecting the structural behavior of the beams and the results of the fire tests are described. Some observations are included relative to proper covering thickness, with qualifications which must be considered in choosing proper thickness.