The Experimental Research On Sulfate Corrosion Of Road Concrete Under Load

Sulfate attack is aggressive media destruction with greater harm of concrete, roadand bridge concrete structure bears its own weight and frequent traffic load. The couplingeffect of corrosive media and load is one of the main reasons for the durability of concretestructures under dynamic and static load. Corrosion media accelerates the accumulation ofconcrete damage and the dynamic and static load also promotes the further development,corrosion damage and load damage promotes each other and leads to the premature failure ofconcrete structures, severely reducing its durability. Therefore, stress corrosion and corrosionfatigue of concrete causes more and more widespread attention of scientists.This paper studies on sulfate corrosion, stress corrosion and corrosion fatigue of roadconcrete by using self-designed stress corrosion and corrosion fatigue loading device, byperfect experimental design and optimization of experimental parameters, studies on theeffect of sulfate species (Na2SO4、MgSO4), sulfate concentration, W/C, stress levels andcorrosion time and other factors for the performance of road concrete, analyses thevariation of the physical and mechanical properties of road concrete under stress corrosionand corrosion fatigue and explores the deterioration mechanism.The following results are obtained:(1) Sulfate attack process of the road concrete is along and slow process and the role of load accelerates the deterioration, according toits destructive effect: corrosion fatigue>stress corrosion>sulfate corrosion.(2) Sulfate species,sulfate concentration and stress levels all have a significant impact on the performance ofroad concrete under load-sulfate corrosion, the corrosion damage Na2SO4>MgSO4, the higherof the sulfate concentration and stress and the worse of its resistance to sulfate corrosion,low W/C can improve the resistance to sulfate corrosion of the road concrete.(3)Combination of laboratory test results, it analyses the reason of load promoting thesulfate corrosion damage of the road concrete and explores the fatigue damage mechanism ofroad concrete under stress corrosion and corrosion fatigue.