Citation

Aktan AE, Farhey DN, Dalal V. Transp. Res. Rec. 1995; 1476: 129-138.

Copyright

(Copyright © 1995, Transportation Research Board, National Research Council, National Academy of Sciences USA, Publisher SAGE Publishing)

DOI

unavailable

PMID

unavailable

Abstract

Nondestructive dynamic field testing and structural identification studies on three steel-stringer bridges (2, 20, and 43 years old) are presented. The bridges were rated by code procedures and by field-calibrated comprehensive three dimensional finite element models developed by structural identification. Experimentally measured and analytically simulated modal flexibilities were correlated with bridge deflections obtained under proof-load level truck load tests. Test results indicated that all three bridges, although constructed as noncomposite, exhibited composite action between the slab and girders. Although the composite action was nearly perfect in the 2-year-old bridge, the older bridges exhibited partially composite behavior caused by deterioration of the chemical bond and friction. The rating factors obtained by field-calibrated models exceeded the corresponding operating rating factors by about 2.5 to 4 times for the three test bridges. The rating process and the resulting factors helped to identify and conceptualize a number of unresolved important issues that influence bridge rating and management. Serviceability aspects that emerged as critical were studied through the relative contributions of various mechanisms to bridge deflections.

Language: en

Keywords

Calibration; Mathematical models; Finite element method; Highway bridges; Structural analysis; Computer simulation; Codes (standards); Deflection (structures); Load testing; Nondestructive examination; Rating; Steel bridges; Three dimensional