Title:
Fire Resistance of Prestressed Concrete Beams
Author(s):
L.A. Ashton and S. S. S. Bate
Publication:
Journal Proceedings
Volume:
57
Issue:
5
Appears on pages(s):
1417-1440
Keywords:
none
DOI:
10.14359/8070
Date:
5/1/1961
Abstract:
Presents the results of an investigation of the fire resistance of prestressed concrete beams with post-tensioned cables, which was carried out by the Joint Fire Research Organization, Boreham Wood Hertfordshire, England, with the cooperation of the Building Research Station. The main object of the investigation was to obtain information on the design of beams for buildings of high fire risk, such as large warehouses, where a fire resistance of 4 hr would be required for structural elements. shown that for normal forms of composite pre-stressed concrete given to the prestressing steel for hard-drawn steel wire, a cover to the beams used in Poor construction, resistance is governed by the protection cable of 1 Y2 in. of concrete is sufficient to give a fire resistance of 1 hr; for longer periods of fire resistance, secondary reinforcement is necessary to hold the concrete cover in place, and a covei of 4 in. gives a fire resistance of 4 hr. By further increasing the concrete cover, fire resistance of up to 6 hr may be obtained. The results of subsidiar tests to determine the effects of load, end-restraint, ad itional di insulation and form of section are presented and discussed, and the effects of partial damage in fire are also considered.