THE EXPERIMENTAL BEHAVIOR OF RC AND HFRC TUNNEL SEGMENTAL JOINTS SUBJECTED TO ELEVATED TEMPERATURE

摘要

The work presented in this paper is focused on the experimental behaviour of TBM tunnel joints in different mechanical boundary condition.The test provides evidences of the thermo-mechanical behavior of joints on their real work conditions under tunnel fire and, therefore, considering several parameters involved in its structural response.Additionally, the test performance over a lining constructed using hybrid fibers as unique concrete reinforcement supplies relevant information about the structural contribution of such material to this structural typology.Thirteen tunnel joint specimens at a scale of 1:3 were tested.: six tests for RC (reinforced concrete) specimens and seven tests for HFRC (hybrid fiber reinforced concrete) specimens.Joints in the post-fire group experienced three different initial loading conditions during heating.The effects of the axial force to joint stiffness were also studied:three different axial force levels were applied in loading condition.