Research On Methods And Devices For Monitoring Corrosion Rate Of Concrete And Steel Structures In Ocean Engineering

Corrosion of reinforcement is the major factor leading to the premature deterioration of global concrete project.Seawater is the most corrosive natural medium and anti-corrosion of concrete and steel structures in seawater is especially critical.For the reason,the operation life of Marine civil engineering is seriously affected.In recent years,quantitative description of corrosion damage degree of concrete and steel structure in seawater has become a research hotspot of corrosion monitoring.Currently,the traditional electrochemical method is used to monitor the corrosion of reinforcement in concrete.However,there are many disadvantages of the method in practical engineering,such as large measurement error,Ac impedance measurement taking a long time.The most prominent problem is that the corrosion rate and corrosion state of the steel bars cannot be obtained directly.In addition,according to these chemical parameters,the corrosion rate and corrosion state of the reinforcement are not able to be obtained.There is less equipment to be used to monitor the corrosion of reinforcement.The research and development of intelligent device to monitor the electrochemical parameters of concrete and steel structure corrosion,and to obtain the rate and the state of corrosion according to these parameters has practical significance.In this paper,we according to the actual demand of Marine engineering,studies the monitoring method of the corrosion rate of Marine concrete and steel structure,and develops a set of intelligent devices for field monitoring.The main work of the paper is as follows:1.The paper studies the development status,measurement methods and characteristics of monitoring technology of concrete and steel structure corrosion.Through the analysis of the principle of constant current step and constant potential polarization based on voltammetry,we obtained the monitoring methods of corrosion rate of Marine concrete and steel structure.2.Based on the monitoring methods of corrosion rate of Marine concrete and steel structure,the simple portable monitoring device is designed.In the device,modular structure is adopted in hardware design,and Composite three-electrode sensor,the constant potential module,the current-voltage conversion preamplifier module,A/D conversion module,and D/A conversion module are completed respectively by using the Keil uVision platform.We realize the communication between main control unit and the wireless transmission module DTU and the remote monitoring using the Tlink cloud platform.3.In simulation experiment design,the system debugging applies three electrode system on the passivation system and activation system testing respectively.We compare the two kinds of state under normal conditions of steel corrosion rate,and the accelerated rate By increasing the improve of NaCl solution in the electrolytic cell,and verify the veracity and reliability of the device's measurement data.Through experimental tests,the data from the intelligent monitoring device in this paper to monitor Marine engineering concrete and steel structure corrosion rate,can accurately reflect the steel corrosion extent.The data remote transmission is normal,and achieves the expected design requirements.The device can be widely used in bridge and other offshore facilities.