Research On Concrete Resistivity And Reiforced Concrete Steel Corrosion Rate

Corrosion rate of steel reinforcement is a very important influence factor for concrete durability. It is significance profound to research the corrosion of steel reinforcement, analyse the different influence factors, and establish the durability model to predict the residual service life of structures.In this paper, the concrete structures in littoral area are our main object to research. The test is studied in laboratory, and research the concrete resistivity and the corrosion of rate. The different influence factors are researched, which include cement dosage, water-cement ratio, temperature, humidity, different mineral admixtures, and so on. In conclusion, this test have established the durability model to predict the residual service life of structures by combining the relationship between width of crack and rebar corrosion ratio, which is researched by others. The research production are as following:(1) Research the influence factors of concrete such as the water-cement ratio, cement dosage per meter cube concrete, chloride content, content of the fly-ash, fine slag and silicon ash, temperature, humidity, and so on. Do the test in laboratory. By means of the test data, analyse the influence regular and degree of all the factors, and establish the model of concrete resistivity.(2) Research the influence factors of concrete such as the water-cement ratio, cement dosage per meter cube concrete, chloride content, content of the fly-ash, fine slag and silicon ash, bar diameter, the cover thickness, temperature, humidity, and so on. Do the test in laboratory. By means of the test data, analyse the influence regular and degree of all the factors, and establish the model of predicting corrosion rate.(3) Establish the model about the relationship between the width of cover crack and rebar corrosion ratio by means of the test data, which is done by others.(4) Analyse the relationship between rebar corrosion ratio and corrosion rate. Establish the durablity model of predicting the service life of structures from t₀ to t₁, which is based on the rule of rust expanding to crack. In this paper, the durability limit state is set that the width of concrete cover is 0.3mm.