TRIS Online Record

Printable View

Title	TEST-TO-FAILURE OF A JACK-ARCH BRIDGE
Accession No	00474211
Authors	Beal, D B
Journal Title	Transportation Research Record No. 1072
Corp. Authors / Publisher	Transportation Research Board
Publication Date	19860000
Description	p. 40-49; Figures(14); References(5); Tables(4)
Abstract	A 76-year-old jack-arch bridge was tested to failure to obtain information on load capacity and the degree of composite action between the steel beams and concrete deck. This work was started because, despite the good condition of the majority of the 1,300 jack-arch bridges in New York, load-rating estimates indicated that they were inadequate to support modern highway traffic. The most likely explanation for the observed performance of these bridges is that they are resisting loads in ways not considered in design or load-rating calculations. Although these bridges have no mechanical shear-transfer devices to assure composite action, it was suspected that chemical bond and friction were sufficient to provide the observed enhancement in load capacity. The 39-ft-span test structure consisted of six 24-in.-deep I-beams spaced at 36 in. Instrumentation consisted of electrical resistance strain gauges on both flanges at midspan, end rotation measurement devices at the ends of two beams, and deflectometers at midspan. The bridge was loaded to produce a 6-ft region of constant moment at the center of the span. Loads were applied through hydraulic jacks reacting against grouted anchors beneath the structure. It is concluded that full composite action may be assumed in load-rating estimates of jack-arch bridges. Although significant restraint of end rotation was also observed in both tests, a generalization of this restraint to other structures is not possible.
Supplemental Information	This paper appeared in Transportation Research Record N1072, Structural Design of Bridges.
TRT Terms	Bridge design ; Bridges ; Chemical bond ; Friction ; Highway capacity ; Load tests ; Structural design
Other Terms	Bridge capacity; Jack-arch bridges; Loading tests; Test-to-failure
Subject Areas	H25 STRUCTURES DESIGN AND PERFORMANCE; I24 Design of Bridges and Retaining Walls
ISBN	0-309-04066-3
Availability	Transportation Research Board Business Office Order Document: http://nationalacademies.org/trb/publications/tris/out_of_print.html Find a library where document is available Order Document: http://worldcat.org/isbn/0309040663
TRIS Files	HRIS
Database	TRIS Online