This code aims to guide the durability design of concrete structures in highway engineering to improve their performance under various environment conditions. It is applicable to the design of concrete structures considering the influence of environmental factors, such as carbonation, freeze-thaw cycle, chlorine salt erosion, etc. The code emphasizes the impact of environment action on the performance of concrete structures, but does not consider Miscellaneous factors such as fatigue, vibration, etc. The design should comprehensively consider the load action and environment action, and determine the durability index, structural structure measures and anti-corrosion measures according to the service life of the structure design, environmental conditions and action grade. It is also necessary to meet the requirements of the current national and industry standards.