UPDATE (27 Nov): You can watch a CCTV9 report about "Lanzhou 1949" here. Trivia: Compare the top photo above with the bridge scene in the film clip. It looks like they filmed on today's bridge, although it would have looked different in 1949. The bridge didn't get the rounded arches until 1954 (see page 6 of this article). There are more photos of the original bridge on the history map.
An additional bit of trivia: a nationalist truck containing explosives ignited and burned down the wooden sections of Zhongshan Bridge, cutting off the north and south banks of the Yellow River. This was first brought to my attention by Bill Schoerner, whose family lived in Lanzhou during the 1940s. He contacted me after an earlier post on this site ("Visitors to Lanzhou in the Early - Mid 1900s") featured his father, Otto Schoerner. He has kindly contributed his recollections:
"At the time of this incident I was four years old and living near the north bank of the Yellow River. My father was the business manager at the Borden Memorial Hospital where I was living with my parents and sister. My older brother was away at boarding school. The Zhongshan iron bridge was the only bridge then and the only route into the city on the other side of the river. One morning in August of 1949, we woke up to much commotion with the news that the bridge was on fire. I remember huge plumes of black smoke and being terrified of the events that were unfolding. While the bridge was being repaired, the only way to cross the river was on a raft made from inflated sheepskins. It is amazing that these photos have been found which confirm my recollections and that this event is being commemorated 60 years later."
In the following photo, you can see the repairs being carried out:
Fighting at Zhongshan Bridge: "Battle to Settle the fate of the Northwest"
Fighting at Shuangchengmen: "60 Years of Photos"
Repairing Zhongshan Bridge: "100 Years of Zhongshan Bridge - 10 Stories" (see page 5)