Experimental Research On Fire Resistance Performance For RC Beams Damaged By Marine Environment With Thermo-mechanical Coupling Effects

In recent years, structural fire occurs more frequently than ever, more and more scholars devote to studying the fire performance of reinforced concrete(RC) structures. As a non- homogeneous material, concrete usually works with cracks, which provides a more convenient path for the transmission of harmful media. However, many researchers ignore the influence of crack onfire performance of RC structures. In this paper, we study the fire behavior of RC beams considering the effects of cracks.In order to study the fire performance of RC beams damaged by marine environment, accelerated corrosion tests were conducted to simulate chloride induced corrosion. In this paper, taking the width of corrosive crack as the damage index. T he change of the mechanical properties of reinforced concrete beams in fire was studied. The main works carried out in this paper are as follows:(1) Summarizing the research results about the durability and fire behavior of RC structures, and introducing the experimental progress of RC beams under fire;(2) Five RC beams were designed to simulate the corrosion damage caused by marine environment. Different widths of cracks were induced for specimens, then fire tests were carried out on these specimens. From the experimental research, we study the distortion theory of temperature field, the load-deformation law and the law of fire endurance.Investigating the relationship between the crack width and fire resistance of RC beams;(3) Measuring the actual corrosion rate of reinforcement, then got the relationship between corrosion rate and fire resistance of RC beams.