Workers are seen at the reconstruction and extension project of Changchun-Lalinhe section of Beijing-Harbin Expressway, northeast China's Jilin Province, July 9, 2019. (Photos: Xinhua)

Workers install sound barrier in hot weather for the reconstruction and extension project of Changchun-Lalinhe section of Beijing-Harbin Expressway, northeast China's Jilin Province, July 9, 2019.

Aerial photo taken on July 9, 2019 shows workers at the reconstruction and extension site of Changchun-Lalinhe section of Beijing-Harbin Expressway, northeast China's Jilin Province.

Workers install sound barrier in hot weather for the reconstruction and extension project of Changchun-Lalinhe section of Beijing-Harbin Expressway, northeast China's Jilin Province, July 9, 2019.

Builders work at the reconstruction and extension site of Changchun-Lalinhe section of Beijing-Harbin Expressway, northeast China's Jilin Province, July 9, 2019.

Aerial photo taken on July 9, 2019 shows workers at the reconstruction and extension site of Changchun-Lalinhe section of Beijing-Harbin Expressway, northeast China's Jilin Province.