Title:
Testing of Double-Tee Concrete Girders for Dade County Rapid Transit System
Author(s):
H. G. Russell, B. G. Rabbat, and T. T. C. Hsu
Publication:
Symposium Paper
Volume:
93
Issue:
Appears on pages(s):
467-490
Keywords:
concrete construction; dynamic loads; flexural strength;
guideways; static loads, T-beams; test equipment; tests; torsion *
tests
DOI:
10.14359/6315
Date:
9/1/1986
Abstract:
Three f u l l -s c a l e , precast, prestressed doub le-tee girders measuring 80 ft (24.4 m) long by 5 ft (1.5 m) deep by 12 ft (3.7 m) wide were con-stru cted. One girder was used to monitor long-term deformations under site conditions. Two girders were tested to demonstrate the adequacy of the girder design, to check construction and reinforcement details, and to verify fatigue performance. Static tests of uncracked and deliberately precracked girders showed that torsional rotations due to service loads were in close agreement with the analysis and were smal 1 enough to ensure rider comfort. Fatigue resis-tance of the girders was verified using two separate test spectra involving 5- and 6-million cycles of loading. The loading represented the cumulative fati gue damage of sixty years of operational llife . Over load tests of the girders showed adequate strength and ductility . A strength of at least 1.6 times the required factored severe derailment load including 100% impact was obtained. The excellent behavior of the girders from serviceability and strength viewpoints substantiated the design methods and construction details used.