There was no cement in ancient times. Why was the Ming City Wall as stable as Mount Tai for 600 years? Modern people are reluctant to use
By 1824, the British construction worker Joseph Aspo had invented the cement and obtained the patent right of Portland cement.
In addition, to prevent cutting corners and craftsmen from perfunctory work, almost every brick and stone is engraved with the name of the responsible worker, so that such Ming Dynasty city walls can withstand gunstones.
It was called Sanhetu.
Tamping soil is the process of compacting the soil to create very strong clay blocks, even stronger than bricks and stones.
The British in 1796 used marl to burn the Roman cement with brown appearance.
The Ming City Wall can stand still today only because the Ming Dynasty used these materials.
As is well known, glutinous rice is a food crop and also a very nutritious food.
Before that, water mud was still a myth.
After Zhu Yuanzhang established the Ming Dynasty, he ordered the widespread construction of cities.
There is another kind of material in the Ming city wall that even modern people can’t bear to use.
It is the world’s longest, largest, and most authentic ancient city wall, and has been selected as the world’s largest city wall by the World Records Association.
Strange news: The Posthouse takes you to a different world.
According to records, 280000 migrant workers have invested in the construction of the Ming City Wall in Nanjing, with approximately 350 million city bricks.
However, without cement, the Ming City Wall had lasted for 600 years, but it was still indestructible.
The use of rammed earth has a long history, and it has been widely used from the Neolithic Age to the 1950s and 1960s.
In 1357, the Ming Dynasty counselor Zhu Sheng suggested to Zhu Yuanzhang that “build a high wall, accumulate more grain, and slowly become the king.” Zhu Yuanzhang felt that the words were reasonable, so he adopted them.
Although there was no cement concrete at that time, special concrete was made by mixing glutinous rice, hydrated lime and limestone, which became very viscous and was the main bonding material, making the bricks and stones of the Ming city wall not deteriorate or damaged for a hundred years.
The Ming City Wall in Nanjing was first built in 1366 and took 28 years to complete in the 26th year of the Ming Hongwu era (1393).
In response, the book “Tiangong Kaiwu” of the Ming Dynasty recorded that when used to support tombs and water storage tanks, one part of the ash was mixed into the river sand, and the other part was loess.
The Ming Dynasty city wall uses both bluestone bricks and rammed soil, which is used inside the wall and further stabilized externally with bluestone bricks.
Why? Modern people are reluctant to use materials.
The mixture was made of glutinous rice and peach vine juice, and it was sturdy and never worn out.
It is glutinous rice.
The Compendium of Materia Medica records that glutinous rice, as a traditional Chinese medicine, has the effects of warming the spleen and stomach, stopping deficiency cold and diarrhea, reducing stools, reducing spontaneous sweating, and causing acne
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During the Spring and Autumn and Warring States periods, the famous Mencius once said, “Shun was born in the field of Guanmu, and Fu Shuo was born in the field of plate building.” Plate building is about the technique of rammed earth.
