Author(s):
H.L. Furr, R. Sinno, L.L. Ingram
Publication Date
1968
Abstract
A numerical procedure using a step-by-step method is used for computing both elastic and time dependent strains, deflections, and prestress losses in full size pretensioned prestressed concrete highway bridge beams. Both lightweight and normal weight structural concretes are used. The method uses creep and shrinkage functions, derived from control specimens, for making predictions.|The computed strains, deflections, and prestress losses agreed well, for the most part, with measured values during the time interval format from date of casting of the slabs to end of tests. The beams were about 320 days old when the slab was cast, and tests terminated at 660-day beam age.|Measured elastic beam deflections under the weight of the plastic slab were a little over 50% of the deflections computed by theory. Prestress losses were about 15% in 40 ft. long lightweight concrete beams at 660 days. The 56 ft. LW beam loss at the same age was about 21% and the NW beam 14 1/2%.|The changes in camber and prestress losses after the slab was cast were minor.
Report Number:
69-3F
Link(s):
Document/Product
http://tti.tamu.edu/documents/69-3F.pdf
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