Photo taken on April 21, 2021 shows an overview of the construction site of the Dafaqu grand bridge of Renhuai-Zunyi expressway in southwest China's Guizhou Province. The bridge, with designed length of 1,427 meters and width of 33 meters, is one of the key projects along the expressway. (Photos: Xinhua/Yang Wenbin)

Aerial photo taken on April 21, 2021 shows an overview of the construction site of the Dafaqu grand bridge of Renhuai-Zunyi expressway in southwest China's Guizhou Province. The bridge, with designed length of 1,427 meters and width of 33 meters, is one of the key projects along the expressway.

Workers operate at the construction site of the Dafaqu grand bridge of Renhuai-Zunyi expressway in southwest China's Guizhou Province, on April 21, 2021. The bridge, with designed length of 1,427 meters and width of 33 meters, is one of the key projects along the expressway.

Aerial photo taken on April 22, 2021 shows an overview of the construction site of the Dafaqu grand bridge of Renhuai-Zunyi expressway in southwest China's Guizhou Province. The bridge, with designed length of 1,427 meters and width of 33 meters, is one of the key projects along the expressway.

Aerial photo taken on April 21, 2021 shows an overview of the construction site of the Dafaqu grand bridge of Renhuai-Zunyi expressway in southwest China's Guizhou Province. The bridge, with designed length of 1,427 meters and width of 33 meters, is one of the key projects along the expressway.

Photo taken on April 21, 2021 shows an overview of the construction site of the Dafaqu grand bridge of Renhuai-Zunyi expressway in southwest China's Guizhou Province. The bridge, with designed length of 1,427 meters and width of 33 meters, is one of the key projects along the expressway.

Aerial photo taken on April 22, 2021 shows an overview of the construction site of the Dafaqu grand bridge of Renhuai-Zunyi expressway in southwest China's Guizhou Province. The bridge, with designed length of 1,427 meters and width of 33 meters, is one of the key projects along the expressway.

A worker operates at the construction site of the Dafaqu grand bridge of Renhuai-Zunyi expressway in southwest China's Guizhou Province, on April 21, 2021. The bridge, with designed length of 1,427 meters and width of 33 meters, is one of the key projects along the expressway.

Photo taken on April 22, 2021 shows a view of the construction site of the Dafaqu grand bridge of Renhuai-Zunyi expressway in southwest China's Guizhou Province. The bridge, with designed length of 1,427 meters and width of 33 meters, is one of the key projects along the expressway.

Photo taken on April 21, 2021 shows an overview of the construction site of the Dafaqu grand bridge of Renhuai-Zunyi expressway in southwest China's Guizhou Province. The bridge, with designed length of 1,427 meters and width of 33 meters, is one of the key projects along the expressway.

Aerial photo taken on April 22, 2021 shows an overview of the construction site of the Dafaqu grand bridge of Renhuai-Zunyi expressway in southwest China's Guizhou Province. The bridge, with designed length of 1,427 meters and width of 33 meters, is one of the key projects along the expressway.

Aerial panoramic photo taken on April 21, 2021 shows an overview of the construction site of the Dafaqu grand bridge of Renhuai-Zunyi expressway in southwest China's Guizhou Province. The bridge, with designed length of 1,427 meters and width of 33 meters, is one of the key projects along the expressway.

Aerial photo taken on April 22, 2021 shows an overview of the construction site of the Dafaqu grand bridge of Renhuai-Zunyi expressway in southwest China's Guizhou Province. The bridge, with designed length of 1,427 meters and width of 33 meters, is one of the key projects along the expressway.

Aerial photo taken on April 21, 2021 shows an overview of the construction site of the Dafaqu grand bridge of Renhuai-Zunyi expressway in southwest China's Guizhou Province. The bridge, with designed length of 1,427 meters and width of 33 meters, is one of the key projects along the expressway.

Aerial photo taken on April 22, 2021 shows an overview of the construction site of the Dafaqu grand bridge of Renhuai-Zunyi expressway in southwest China's Guizhou Province. The bridge, with designed length of 1,427 meters and width of 33 meters, is one of the key projects along the expressway.

Aerial photo taken on April 22, 2021 shows an overview of the construction site of the Dafaqu grand bridge of Renhuai-Zunyi expressway in southwest China's Guizhou Province. The bridge, with designed length of 1,427 meters and width of 33 meters, is one of the key projects along the expressway.

Aerial photo taken on April 21, 2021 shows an overview of the construction site of the Dafaqu grand bridge of Renhuai-Zunyi expressway in southwest China's Guizhou Province. The bridge, with designed length of 1,427 meters and width of 33 meters, is one of the key projects along the expressway.