FLEXURAL BEHAVIOR TEST AND BEARING CAPACITY CALCULATION OF STEEL REINFORCED RECYCLED AGGREGATE CONCRETE BEAMS AFTER HIGH TEMPERATURE

In order to reveal the flexural failure mechanism of steel reinforced recycled aggregate concrete ( SRRAC) beams after high temperature，twelve SRRAC specimens were designed for monotonic loading experiment at ambient temperature，200，400 and 600 ℃． The experiment involved high temperature and the replacement rate of recycled coarse aggregate． Appearance changes，the failure processes，and forms of specimens at different temperatures were observed，the load-displacement curves， cross-sectional stress distribution， ultimate load and other important information were obtained． And the effecting law of each changing parameter on the SRRAC beams’mechanical behavior after high temperature was analyzed． Results showed that the failure mode of SRRAC beams after high temperature was similar to that at ambient temperature． The SRRAC beams after temperature had good deformation performance after ultimate load，but the ultimate bearing capacity of beams after 600 ℃ reduced obviously，the bearing capacity of full recycled aggregate concrete beams decreased most seriously． Finally，the residual flexural bearing capacity calculation methods of SRRAC beams after high temperature were proposed．