MPC Research Reports
Report Details

Title:	Field Investigation of a Strengthened Timber Trestle Railroad Bridge
Authors:	Richard M. Gutkowski, Abdalla M.T. Shigidi, and An Vihn Tran
University:	Colorado State University
Publication Date:	Jun 2003
Report #:	MPC-03-147
Project #:	MPC-137
TRID #:	00950561
Keywords:	evaluation, railroad bridges, wooden bridges

Abstract

A three-span, open deck timber trestle railroad bridge had been previously field load tested. The prior testing program was done in cooperation with the Transportation Technology Center, Inc., a subsidiary of the Association of American Railroads. The bridge was subjected to static and moving train loads as well as controlled actuator ramp loading. The bridge was later strengthened by the addition of helper stringers. The bridge was load tested again by moving train loads. Comparisons of the stiffness of the bridge were made before and after the strengthening. The efficiency of the helper stringers was between 82 percent and 97 percent. Load sharing among stringers was determined empirically. No pattern of load sharing among them could be identified but individual stringers carried up to 9 percent more load share than in an equal load sharing distribution. The transient displacement responses showed predominantly no dynamic impact effect, but isolated increases of 6-10 percent were observed.

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• [Final Report] Field Load Tests of Open-Deck Timber Trestle Railroad Bridges