Evaluate Mao Yisheng, Mao Yisheng s main achievements

Construction of the Qiantang River Bridge.

From 1933 to 1937, Mao Yisheng.

He served as the director of the Qiantang River Bridge Engineering Department and presided over the construction of China's first modern bridge, the "Qiantang River Bridge". He used the "water injection method", "caisson method" and "floating method" to solve the technical problems in bridge construction. Since then, Mao Yisheng's footprints have spread all over the country, and his name and the newly built bridge have also remained throughout the country.

After five years of hard work, Mao Yisheng finally built the modern Qiantang River Bridge. September 26 is the 74th anniversary of the completion and opening of the Qiantang River Bridge.

The Qiantang River Bridge began in 1934. At that time, the Zhejiang-Jiangxi Xunzheng Railway was under construction, and in order to connect with the Shanghai-Hangzhou Railway, a bridge had to be built over the Qiantang River. The Qiantang River is a well-known and treacherous river, and the hydrogeological conditions are extremely complex.

Its water potential is affected not only by upstream flash floods, but also by downstream sea tides.

Fluctuations are conditioned. In the event of a typhoon, the river is often rough. The quicksand at the bottom of the Qiantang River is 41 meters thick, unpredictable, so it is called "the bottomless Qiantang River".

Therefore, there is a folk proverb that "it is impossible to build a bridge on the Qiantang River", and the engineering and technical circles also believe that it is a very difficult thing to build a bridge on the Qiantang River. Mr. Suinian Mao Yisheng aspired to work as a bridge, but later lost his career in the United States. He was at Cornell University.

and Carnegie Mellon University School of Technology, where he specialized in bridges and earned his Ph.D. He was saddened to see that the steel bridges on the rivers of his motherland were all built by foreigners, and he was determined to make a difference for the Chinese and build his own bridges. So, in the face of the difficulties, I was appointed as the director of the bridge engineering department, and invited Luo Ying, a classmate from Cornell University.

Be the chief engineer.

The first difficulty encountered in building the bridge was piling. In order to stabilize the foundations, 1,440 wooden piles were driven into nine piers, through 41m thick silt, and the wooden piles stood on the stone layer. The sand layer is thick and hard, and the light ones can't go down, and the heavy ones break the pile.

Inspired by the practice of watering the soil out of the small hole, the "water shooting method" was used to pump the river water into the deep holes in the thick and hard sediment and then drive piles, so that the original piling in one day and night increased to 30 piles, which greatly accelerated the construction progress. The second difficulty encountered in the construction of the bridge is that the water flow is fast, and the construction is difficult. Mao Yisheng invented the "caisson method", that is, the use of reinforced concrete.

The mouth of the made tank is sunk into the water, covered by the bottom of the river, and then the water inside the tank is squeezed out with high-pressure gas. Workers dig sand in the boxes, so that the caissons and stakes gradually merge into one. Construction of piers on caissons.

Placing the caisson is not easy. At first, a caisson was swept downstream by the river, upstream, and up and down. Later, the 3-ton iron anchor was changed to 10 tons, and the caisson problem was solved.

The third difficulty is the erection of steel beams. Mao Yisheng adopted the "floating method" that cleverly uses the forces of nature. When the tide is high, the steel beam is transported between the two piers by boat, and when the tide falls, the steel beam falls on the two piers, which saves labor and time, and the progress is greatly accelerated.

Mao Yisheng is the father of bridges in China. He presided over the construction of the first bridge that China saw independently, the Qiantang River Bridge. It has made great contributions to China's bridge construction.

The overall structure of the bridge is very stable, and the current Qiantang River Bridge has been built into a double-decker railway and highway bridge. Today, driving on the bridge can still make people sigh that 80 years ago, the Chinese were able to build a bridge that stood for a hundred years.

Mao Yisheng is known as the father of Chinese bridges, a civil engineer, bridge expert, and engineering educator. In the 30s of this century, he presided over the design and organization of the construction of the Qiantang River Highway and Railway Bridge, which became a milestone in the history of China's railway bridges and made outstanding contributions to the construction of bridges in China.

He has presided over the transformation of the Chinese Academy of Railway Sciences for more than 30 years, and has made outstanding contributions to the progress of railway science and technology. He is a pioneer who actively advocates the application of soil mechanics in engineering.

In engineering education, he pioneered the heuristic education method, insisted on integrating theory with practice, and devoted himself to educational reform, which has cultivated a large number of scientific and technological talents for China. He has served as the leader of the society for a long time, and is one of the founders of China's engineering academic group.