In seismic design of steel beam for building, lateral brace is a common lateral support device used nowadays to prevent the lateral torsional buckling. Lateral brace will restraint the lateral displacement at the bottom flange of H shaped beam. The lateral displacement of the top flange will be restrained by floor slab. But, the floor slab seems not only can restrain the lateral displacement but also can provide lateral torsional stiffness to the beam. In this test, one beam with lateral brace and three beams without lateral brace were tested. All of the beams have slab casted on them. Two special detailing were used for the beam without lateral brace to prevent the bottom flange deformation besides of lateral brace.
The test results show that, the slab can increase the ductility of the steel beam compare to the beam without slab (ABRI report). The beam can exhibit a very good ductility although lateral brace is not provided when the slab is in presence. The local buckling and lateral torsional buckling are concentrated at the reduced section region when slab is in presence.

In seismic design of steel beam for building, lateral brace is a common lateral support device used nowadays to prevent the lateral torsional buckling. Lateral brace will restraint the lateral displacement at the bottom flange of H shaped beam. The lateral displacement of the top flange will be restrained by floor slab. But, the floor slab seems not only can restrain the lateral displacement but also can provide lateral torsional stiffness to the beam. In this test, one beam with lateral brace and three beams without lateral brace were tested. All of the beams have slab casted on them. Two special detailing were used for the beam without lateral brace to prevent the bottom flange deformation besides of lateral brace.
The test results show that, the slab can increase the ductility of the steel beam compare to the beam without slab (ABRI report). The beam can exhibit a very good ductility although lateral brace is not provided when the slab is in presence. The local buckling and lateral torsional buckling are concentrated at the reduced section region when slab is in presence.

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