A total of 12 specimens with two different cross sections were tested under cyclic double curvature moment. Anti-buckling elements for preventing lateral torsional buckling are attached to five beam specimens tested in this experimental study. The result shows that all of the specimens tested can develop sufficient strength and exhibit adequate ductility. However, for the beam without any anti-buckling element installed and not properly braced, the twist angles are very large. The used of the anti-buckling element to the beam members can suppress the twist angle effectively as long as the anti-buckling elements have sufficient moment of inertia or length. The moment of inertia and length of the anti-buckling element are important parameters to the performance of anti-buckling element. Furthermore, the presence of top lateral bracing and L/ry ratio of the cross section affect the stiffness and length requirement of anti-buckling element.

A total of 12 specimens with two different cross sections were tested under cyclic double curvature moment. Anti-buckling elements for preventing lateral torsional buckling are attached to five beam specimens tested in this experimental study. The result shows that all of the specimens tested can develop sufficient strength and exhibit adequate ductility. However, for the beam without any anti-buckling element installed and not properly braced, the twist angles are very large. The used of the anti-buckling element to the beam members can suppress the twist angle effectively as long as the anti-buckling elements have sufficient moment of inertia or length. The moment of inertia and length of the anti-buckling element are important parameters to the performance of anti-buckling element. Furthermore, the presence of top lateral bracing and L/ry ratio of the cross section affect the stiffness and length requirement of anti-buckling element.

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