الفهرس | Only 14 pages are availabe for public view |
Abstract The design the over-hanging mono-symmetric I-beams is not sufficiently covered in the current standards and specifications. The buckling length specified in the current standards and specifications was firstly defined by Nethercot, 1973 and covered only doubly symmetric I-sections. In this research program, both experimental and theoretical programs were performed to study the elastic and inelastic lateral torsional buckling behavior of mono-symmetric I-sections bent about the major axis. In the experimental program, six full-scale over-hanging beams were tested. The back-span length was 2000 mm and the over-hanging lengths were variable and had the lengths of 1000, 2000 and 3000 mm. The tip of the cantilever had two cases of bracing: top and bottom flange laterally restrained, and free. The cross section considered in the test program had degree of mono-symmetry (ratio of the second moment of area about minor axis of the compression flange to the seconded moment of area about the minor axis of both the compression and tension flanges) r = 0.82. The root and end support were laterally and torsionlly restrained (fork support). The mid-length of the back span was laterally supported to prevent lateral torsional buckling failure in this part. The specimens were subjected to a concentrated load applied at the top flange at the tip of the cantilever. |