Study On Bending Performance Of Reinforced Concrete Beams Mixed With Lithium Slag In Simulated Acid Rain Environment

Lithium slag is an industrial waste residue in industrial production of lithium. At present, a lot of researches have been made at home and abroad. It has been indicated that lithium slag is a rare high activity admixture in concrete. The application of concrete mixed with lithium slag can not only save the cement, reduce the cost of the project, but also can solve the environmental problems brought by the industrial waste residue. Acid rain is often considered as one of the worst corrosion conditions in the present. The service life of concrete structures subjected to acid rain corrosion is much lower than that of the design life. But at present, the research on the corrosion of acid rain on concrete is focused on the concrete, and the research on the corrosion of concrete components has not yet been carried out.In this paper, lithium slag form Jiangxi province is mixed in concrete, taking reinforced concrete beams mixed with lithium slag as the research object, and referring to the chemical composition of acid rain area of Jiangxi province, the bending performance and corrosion resistance of reinforced of reinforced concrete beams mixed with lithium slag are researched. The main works are as follow:(1) 8 reinforced concrete beams mixed with lithium slag and 4 ordinary reinforced concrete beams were designed with the main parameters of lithium slag replacement ratio and reinforcement ratio. Pure bending test was researched on 12 test beams, the flexural failure patterns of the test beams were observed, the relationship between the substitution rate of lithium slag and the cracking and ultimate bending moment of the test beam was analyzed, the formula in the current code was used to calculate bearing capacity of concrete beam mixed with the lithium slag.(2) Artificial rainfall device was used to simulate acid rain, 5 lithium slag concrete beams and 5 ordinary concrete beams were sprayed to corrode, the appearance of the test beams were observed, and the corrosion damage thickness of test beams with different corrosion time was measured by ultrasonic testing method.(3) Pure bending test was researched on the beams subjected to different corrosion time, the cracking moment and ultimate bending moment of the beams with different corrosion degrees were obtained. The effects of the thickness of the corrosion damage on the cracking moment and the ultimate bending moment of the two kinds of concrete beams were compared.(4) SEM was used to observe the surface microstructure changes of test beams with different corrosion time.