Corrosion Behaviors of 20 Steel in Different Types of Soil Simulated Solution of Beijing

As the biggest heat-supply city in china, the soil corrosion of heat-supply pipelines buried in Beijing underground has an important significance as well as practical application value. The corrosion behaviors of 20 steel in four different types of simulated soil solution as well as the electrochemical behaviors in soils under the bridge were investigated. The results show that localized corrosion existed in soils under the bridge and city main roads. However, the corrosion behavior of 20 steel in the soils under urban grassland and residential areas was mainly general corrosion. After 60-days immersion, the ranking of corrosion rates of 20 steel in simulated soil solutions was in soil under the bridge > in soil under city main road > soils under residential areas in soil under urban grassland. The electrochemical measurements through the simulation solution of soils under the bridge showed that the corrosion of 20 steel didn't continue in the strong corrosive soil under the bridge since. the accumulation of corrosion products on the sample surface tesulted in a protective effect on the substrate and finally decreased the corrosion rates with the poogress of reactions.