The project of “Research and application of key technologies of high performance concrete for highway bridges and culverts under severe environmental conditions” by YCIH Green High-Performance Concrete Company Limited won the second prize of 2020 CCPA Concrete Science and Technology Award (Technology Innovation).

Shangrila–Lijiang Expressway is the green low-carbon highway pilot project of the Ministry of transport, and it is also the expressway with the highest altitude in Yunnan Province. The project has a total length of 140.31km, 141 bridges and 73114m tunnels along the whole line, of which the average altitude of Shangrila section is 3280m, with the following characteristics:

l Three highs: high altitude - 3280m, large elevation difference - 1100m, high seismic intensity -Ⅷ

lTwo complex: complex terrain and geology

lOne fragile: fragile ecological environment

lOne arduous: extremely arduous project. The climatic conditions are very severe. The extreme temperature can reach -27.4℃ and the temperature difference between day and night can reach more than 20℃.

Construction of bridge

There are two difficulties of high performance concrete for bridges and pavements of Shangrila–Lijiang Expressway:

lLack of high-quality mineral admixture and high-quality natural aggregates;

lThe largest asymmetric single tower single span ground anchored suspension bridge requires high concrete performance and great technical difficulty.

YCIH Green High-Performance Concrete Company has systematically carried out a series of research, realized the application of high-performance concrete in Expressway and bridge construction projects, and has the following innovation.

Construction of Jinsha River Bridge

lAccording to the characteristics of regional raw materials and climate, a mix proportion design method of limestone waste chips concrete with high stone powder content is formed.

lAccording to the severe climate and environmental conditions, based on the durability of concrete, the key technical parameters of mix proportion of high-performance concrete for expressway bridges are put forward, and a series of high-performance concrete products are developed.

lForm key technologies for complete preparation and quality control of concrete in low temperature and high altitude areas.

lThe research and development of high-performance concrete for the world's largest asymmetric single tower and single span ground anchored suspension bridge has formed key application technologies and solved the technical problems of high crack resistance and high durability of concrete under complex terrain conditions.

Construction in winter

There were totally 3 million cubic meters of high-performance concrete in this project, which improved the structural life of expressway project under severe environment, and laid a solid foundation for the opening of Shangrila–Lijiang Expressway on December 31, 2020.

Construction of bridge