Study On Durability Of Reactive Powder Concrete After Damage

With the large-scale construction of infrastructure, concrete structures face the challenges of harsh corrosion environment. Due to its high strength, high toughness and good durability, reactive powder concrete (RPC) have broad application prospects in many areas, especially suitable for the structures that have high demand on durability and for the structures used in harsh environments. As in the actual project,components will be subject to the load, and load will cause some damage to the structure, so study on the durability of reactive powder concrete after damage has very important meaning for its future practical application. In this paper, the durability of reactive powder concrete after damage were studied, the major work and conclusions are as follows:(1) In order to study the durability of Reactive powder concrete after damage, The specimens of reactive powder concrete with fiber content 2%and 0%were loaded to 60%,70%,80%to its peak load,so as to simulate different degree of damage. The specimens of C50 concrete was loaded to 50%,60%,70%of its peak load so as to simulate different degree of damage. tested damage by measuring the base vibration frequency of the specimen and found that the base vibration frequency decay exponentially as the load level increases.(2) Different load levels specimens of reactive powder concrete with fiber content 2% and 0%,and different load levels specimens of C50 concrete were done an experiment to test their resistance to chloride ion penetration, found that the migration coefficient of chloride ions increases with the increases of load degree. The chloride migration coefficient of reactive powder concrete at different load level maintaines at 1×10-13～1×10-12m2/s in magnitude,The chloride migration coefficient of C50 concrete maintaines at 1×10-9m2/s in magnitude;(3) Different load levels specimens of reactive powder concrete with fiber content 2%and 0%,and different load levels specimens of C50 concrete were done an experiment to test their resistance to single freeze-thaw. Discovered that the base vibration frequency decrease during the freeze-thaw cycle and the quality of the reactive powder concrete specimen is stable, the quality of the C50 concrete specimen decrease during the freeze-thaw cycle;(4) Different load levels specimens of reactive powder concrete with fiber content 2% and 0%,and different load levels specimens of C50 concrete were done an experiment to test their resistance to sulfate attack. Discovered that the base vibration frequency increase firstly,and then decrease during the freeze-thaw cycle and the quality of the reactive powder concrete specimen is increase, the quality of the C50 concrete specimen decrease during the wet and dry cycle,the wet and dry cycle can lower the flexural strength of the specimens.