What stones are bonded together in the Great Wall of Wan Li? There was no cement mortar and tile binder in ancient times.

Yellow mud was used before the Song Dynasty, and lime mortar was widely used after the Song Dynasty. In the Ming Dynasty, lime mortar and glutinous rice juice were widely used as cementing materials when building city walls, which greatly increased the cementing force. In many sections of the Great Wall in the Ming Dynasty, glutinous rice juice was mixed with mortar. Until today, the mortar bonding force between brick joints is still very strong.

Based on the principle of "using local materials and teaching students in accordance with their aptitude", many structural methods have been created. There are rammed earth, rubble, masonry and other structures; A layer-by-layer structure of reeds and sand.

The Great Wall of the Ming Dynasty was mainly built with a material called rammed earth. This method of tamping soil mainly uses red mud, coarse sand and lime blocks.

Later, when the Great Wall was built, a material called glutinous rice soup was changed. This material can be said to be very sticky. This thing is the best choice, and the standing of the Great Wall also has its credit.

The adhesive power of glutinous rice soup is beyond people's imagination, so it is widely used to bond buildings, and glutinous rice soup is no less than our current materials.

The wall of the Great Wall The Great Wall was built on a high mountain or plain, and it was built according to the needs of topography and defense function. It is very tall and strong in the plains or important passes, and low and narrow in the dangerous places of high mountains.

In order to save manpower and cost, even some steep places can not be built conveniently, and the methods of "dangerous mountain wall" and "splitting mountain wall" are adopted. In Juyongguan, Badaling, Hebei, Shanxi, Gansu and other areas, the average height of the Great Wall is about 7 or 8 meters, the bottom thickness is about 6 or 7 meters, and the top width is about 4 or 5 meters.

On the top of the city wall, there is a building wall inside, which is 1 m high to prevent patrol soldiers from falling. Outside is the crib wall, about 2 meters high. The upper part of the stack wall is provided with a lookout, and the lower part is provided with a shooting hole and a rolling stone hole, which are used for observing the enemy situation and shooting rolling stones.

On the top of some important city walls, there are layers of barriers to resist the enemies who climb the city walls in case. In the middle of Ming Dynasty, when the famous anti-Japanese star Qi Jiguang was transferred to Yuji Town as the company commander, the fortifications of the Great Wall were greatly improved, and enemy towers or platforms were set at the top of the wall to accommodate patrol soldiers and store weapons, food and socks, which greatly strengthened the defensive function of the Great Wall.