Matsui RKoizumi KLin P.-CIwanaga MWu A.-CTakeuchi TTsai K.-C.KEH-CHYUAN TSAI2022-03-222022-03-22202107339445https://www.scopus.com/inward/record.uri?eid=2-s2.0-85105787049&doi=10.1061%2f%28ASCE%29ST.1943-541X.0003017&partnerID=40&md5=8589cae331dc42d446d3850e3d8f9a82https://scholars.lib.ntu.edu.tw/handle/123456789/598533This paper introduces a grid-purlin system, which was composed of secondary rectangular-hollow-section grids welded onto the top flange of I-shaped beams of moment frames. The welded grid-purlin itself may play a role of a lateral bracing member for the welded beam. However, the ultimate strength, plastic rotation capacity, or other structural characteristics of this grid-purlin system remain poorly understood. This paper presents two full-scale cyclic loading tests on specimens with I-shaped beams 700 mm deep, 240 mm wide, and 13 m long. The diagonal length of grids in the square grid-purlin of the specimen was 1.3 m on-center, and two different depths of the sections were selected for the purlin sections. Both specimens successfully achieved fully plastic moments at a plastic rotation exceeding 0.04 rad. This shows that the grid-purlin system provides reliable lateral bracing. Continuum finite-element (CFE) analysis was performed to simulate the hysteretic experimental response of the grid-purlin system. This CFE model was used to examine the plastic rotation capacity for a variety of combinations of I-shaped beams and grid-purlins. ? 2021 This work is made available under the terms of the Creative Commons Attribution 4.0 International license,.BeamCyclic loading testPlastic rotation capacityPurlinStability bracing of beamsCyclic loadsSteel beams and girdersWeldingLateral bracingMoment framesPlastic rotationRectangular hollow sectionsStructural characteristicsUltimate strengthRotation[SDGs]SDG11journal article10.1061/(ASCE)ST.1943-541X.00030172-s2.0-85105787049