Performance Study And Demonstration Engineering Application Of Marine Reinforced Concrete Protective Coating

The corrosion environment of ocean has the huge influence on the safety of reinforced concrete in ocean,therefore,it is necessary and extremely urgent to implement the anti-corrosion to the main structure of reinforced concrete.The reinforced concrete coating,one anti-corrosion protection technology,is the most effective method to enhance and improve the durability of the main structure of reinforced concrete in ocean.This paper selected four different anti-corrosion coating materials,such as four layers of epoxy coating(film-forming coating),wet curing epoxy coating,polyurea,osmotic coating silane,to brush the specimens of reinforced concrete,respectively.After that,the basic performance tests,such as coating adhesion,crack tracking,alkali resistance,salt spray resistance,aging resistance,chloride ion erosion resistance,were implemented to comprehensively evaluate the durability of selected coating materials.The main contents of this paper is reported as follows.(1)adhesion study shows that the polyurea coating has the maximum adhesion(6.27MPa),the four layers of epoxy coating has the medium adhesion(5.13MPa),and the wet curing epoxy coating has the minimum adhesion(4.83MPa).All of them can satisfy the anti-corrosive coating adhesion standards.(2)according to the fracture follow-up test,the polyurea coating has the best fracture follow-up displacement of the coating film(11.49mm),the four layers of epoxy coating has the perfect fracture follow-up displacement of the coating film(1.22mm),and the wet curing epoxy coating has the worst fracture follow-up displacement of the coating film(0.46mm),which indicates it is crunchy.(3)according to the alkali resistance and salt fog resistance test,we can see that the four layers of epoxy coating,wet curing epoxy coating,polyurea,have the better performance,and their failure grade,pulverization grade,foaming grade and peeling grade are all 0 level.Compared with film-forming coating,osmotic coating silane has poor performance in alkali resistance and salt fog resistance,and its failure grade,pulverization grade and foaming grade are 1 level,and peeling grade is 0 level.(4)according to the aging resistance test,it can be seen that the best one is four-layer supporting epoxy coating,whose light loss grade and discoloration grade are 1 level;the second one is polyurea coating,whose loss of light grade,discoloration grade are 2 level;The light grade,discoloration grade of wet curing epoxy coating are 3 level;(5)according to the chloride ion electromigration test,it can be seen that the chloride ion diffusion coefficient of silane of the above selected materials are 0.75 x 10-12 m~2 / s,3.00 x 10-12 m~2 / s,0.50 x 10-12 m~2 / s,9.00 x 10-12 m~2 / s,respectively.However,the ability to resist chloride ion erosion of polyurea,four layers of epoxy coatings,moisture curing epoxy coatings and silane are reduced in turn.(6)taking Rizhao port as a application example,the four-layer supporting epoxy heavy anti-corrosion coating was used to protect and repair concrete structures,which gradually improved the construction process and provided a reliable basis for the future development and application of Marine reinforced concrete special anti-corrosion coating.