EXPERIMENTAL RESEARCH ON FIRE RESISTANCE PERFORMANCE FOR RC BEAMS WITH DAMAGE CAUSED BY MARINE ENVIRONMENT

摘要

Deformation, bearing capacity and seismic resistance of members were damaged after fire,which affected durability and safety of structures especially along the seaside.Concrete reinforcement was eroded by chloride ion in the sea water.In order to avoid the collapse or the damage of the coastal concrete structure in fire, it is particularly important to research the loss of the bearing capacity of the structure or components under the high temperature.In this paper, in the method of impressed current to accelerate corrosion, the corroded reinforced concrete beams were obtained and crack width is the indicator of damage.Under the coupled action of high temperature and marine environmental damage,the flexural performance of reinforced concrete beam is studied.The research contents include:(1) Four RC beams were designed to develop different crack widths caused by chloride ion erosion test.The five members were set on fire and then obtain the data on the temperature field of the beam section.(2)All the members were loaded after fire test in order to obtain the residual bearing capacity.Compared with the load data, bearing capacity degeneration of the damaged beams after fire was discussed in the paper.