Experiment and analysis on mechanical properties of Fully-Grouted sleeve connection at elevated temperatures

The performance of the prefabricated concrete (PC) structures at elevated temperature becomes an important focus, once a fire occurs. The failure in fire of fully-grouted sleeve connection (FGSC) that extensively used in PC members will cause serious consequences. To fill this knowledge gap, the present work presents the experimental results of 15 FGSC specimens and 15 single rebar (SR) specimens by static tension. The results show that the mechanical behavior of FGSC specimens at high temperature is affected by the temperature and similar to that of SR. Two types of failure modes appear in the FGSC specimens, namely, rebar tension fracture and bond failure. The bond failure was observed at 600 °C. Based on the test results, the tension constitutive relation curves was established, and the bond strength design of FGSC at elevated temperatures were put forward to avoid the bond failure. A new prediction method for calculating mechanical property of prefabricated rebar connection at elevated temperature is proposed.