Effect on the Resistance of Concrete Acid Corrosion in Superficial Soil Layers

Abstract

To understand the effect and mechanism of urban heat island (UHI) and the acid corrosion of concrete on the strength of concrete in superficial soil layers from Nanjing area, both laboratory and field tests of accelerated corrosion of concrete were carried out and analyzed. The laboratory test results indicate that the concrete corrosion depends on acid concentration, tested time, and also on the temperature. The maximum corrosion coefficient (K-value) of 45.86%, as observed at 10% of acid concentration, 40°C of tested temperature, and 90 days of tested time, was about 2 times that of specimens with 10% of acid concentration, 5°C tested temperature, and tested after 90 days. The field test showed that the compressive strength of specimens in urban station was lower than that of specimens in rural station. The K-value of specimens with same acid concentration observed at urban area was higher than that of specimens at rural area. Both the laboratory and field tests showed that the temperature has an increasingly powerful influence on the concrete corrosion under acid environment. Therefore, the UHI effect will accelerate the acid corrosion in concrete construction and may affect the stability and durability of buildings in urban areas. The safety and life assessment of concrete buildings therefore require great attention.