Abstract
The process of designing a typical simply supported girder for service loads is well established. However, the fact that the girder will be suspended by cables during the erection phase affects the safety of the girder. An adequate design necessitates that the girder not only be designed so that it will safely support the service loads it will be subjected to once it is in place and performing its intended function but, in addition, it must also be designed to safely sustain forces during the erection process. Initial camber, such as in the case of prestressed concrete girders, aggravates the problem. The presence of camber causes the resultant of the load to be located above the center of torsion of the member, thus causing an increase in torsional moment with increasing lateral displacement. This behavior reduces the critical buckling load of the member and the safety of the girder. This dissertation develops the differential equations necessary to obtain the critical buckling load for a member subjected to its own weight during lifting. Support conditions considered include (a) simply supported, (b) suspended by cables at the ends, and (c) suspended by cables located an equal distance from the ends of the member. All cases are considered with and without the presence of camber. Finally, sample graphs of the results are included to aid in the discussion of the significance of camber in calculating the critical buckling load of a member. Also, a FORTRAN code listing is provided to aid in the manipulation of the complex mathematical expressions.
Peart, Walter Lee (1990). Buckling of suspended cambered girders. Texas A&M University. Texas A&M University. Libraries. Available electronically from
https : / /hdl .handle .net /1969 .1 /DISSERTATIONS -1190562.