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To investigate the shear capacity of indirectly loaded reinforced concrete beams under and after fire exposure, load tests were conducted on eight full-scale specimens exposed to fire testing in a furnace chamber, and the effects of additional transverse reinforcement in the junction region between the primary and secondary beams on the shear capacity, fire resistance, failure modes and deflection were analysed. The results indicate that the slopes of the diagonal cracks in post-fire tested reinforced concrete beams without additional transverse reinforcement were shallower than those of a similar reference beam not exposed to fire, and that the ultimate capacities of reinforced concrete beams with additional transverse reinforcement decreased obviously after fire exposure. However, beams with additional transverse reinforcement exhibited increased fire resistance times and reduced strains in their reinforcement, indicating the benefit of conservatively providing such reinforcement. The findings of this study are expected to provide a reference for the improved fire-resistant design of indirectly loaded beams. [ABSTRACT FROM AUTHOR]

With high strength and good seismic performance, T-shaped steel reinforced concrete column is widely used in high-rise building structure. Three T-shaped steel reinforced concrete columns were tested under high temperature and vertical load, to simulate fire effect. The test results indicate that failure characteristics, distribution of temperature field, vertical deformation characteristics and fire resistance were comparatively analyzed under different axial compression ratios and different eccentricity. The test also indicated that the cracks increased with the increase of axial compression ratio and eccentricity. The damages of web were severer than the flange. The cracks were mainly distributed on the eccentric side and mostly inclined cracks in specimen. The vertical expansion became more obvious as the eccentricity decreased. The fire resistance decreased as the axial compression ratio increased. Compared with, the fire resistance of large axial compression specimens (the axial compression ratio is 0.6) were decreased by 57% than small axial compression specimens (the axial compression ratio is 0.2). The fire resistance decreased by about 30min as eccentricity increased by 20mm. [ABSTRACT FROM AUTHOR]