INFLUENCE LINES FOR TWO AND THREE SPAN CONTINUOUS CURVED GIRDER BRIDGES

A series of influence line tables and equations have been presented, which will permit an initial design of a two or three span continuous bridge. The design technique is applicable to both dead and live loads applied perpendicularly to the plane of the structure or as torsional moments applied along the longitudinal axis parallel to the plane of the structure. The design procedure is based on the relative behavior of a single isolated curved girder to the response of the same girder when acting in conjunction with a system of curved girders. Therefore, by applying appropriate factors, the system response can be determined from the single girder forces as computed from the influence line charts. This affords a simplified, methodical approach toward the design of multi-span curved girder bridges. The method developed, herein, will negate the need to apply complicated mathematical expressions or sophisticated computer programs to permit an initial design of continuous curved bridges. /FHWA/