The Earthquake Engineering Online Archive

Model studies of curved box-girder bridges

Aslam, Mohammad; Godden, William G.

UCB/SESM-1973/05, Dept. of Civil Engineering, University of California, Berkeley, 1973-03, 121 pages

This report presents the results of laboratory tests on a series of 1/29 scale aluminum models of curved box-girder bridges. The tests were conducted primarily to provide experimental response data to check the accuracy of proposed analytical solutions for the elastic behavior of bridges of this type. The prototype design was a four cell box section with a total width of 33 ft 10 in., the radius of curvature was 282 ft in all cases, and the span varied from 145.0 ft to 72.5 ft. All tests were conducted on a single machined aluminum model. Starting with the longest span of 60 in. the model was cut back to 45 in. and 30 in. spans respectively. All models were tested both with and without a midspan radial diaphragm for 10 different locations of a single vertical point load. Reactions were measured by four load cells, deflections at 9 locations by low voltage differential transformers, and strains by 68 rosette gages and four single-element gages located on a radial section close to midspan. All load and strain readings were recorded and reduced by computer, and these data were checked for self-consistency by three independent static checks. The data presented in this report include external reactions, deflections at selected points along the webs, tangential plate forces and radial plate bending moments on a radial section close to midspan. Also deduced in each test is the distribution of total moment at midspan between the individual I-beams that comprise the box section. The report concludes with some observations on the general behavior of the curved box-girder bridges tested and a brief comparison of test and theoretical results.

Available online: http://nisee.berkeley.edu/documents/SEMM/SEMM-73-05.pdf (13 MB)