"Father, this time the retainer is on the island, and there is a new discovery."

"Oh?"

Qingji came to the interest.

It goes without saying where Wajima is.

The state of Wu had already initially established its rule on the island.

Several castles were built, but they were not administered by counties, so they were considered overseas.

Gongzi was worried and asked people to bring a burden, and took out a handful of plaster from the burden.

"Is this volcanic ash?"

"Exactly."

"Sorrow, what's so strange about volcanic ash?"

Qingji was a little disappointed.

Having said that, China is a vast land, and it is not without volcanoes.

For example, the three counties of Hebei in Wu State, as well as the southwest and Lingnan areas have volcanoes, but most of them are in the dormant period and will not erupt.

"Father, this island is full of volcanoes, earthquakes, and tsunamis. This volcanic ash is indeed not an unusual thing to you, father, but in the eyes of the sons, it is very useful!"

"Father, please see."

Gongzi took out a piece of cement and handed it to Qingji.

"Cement?"

Only then did Qingji remember that volcanic ash did play an important role.

When a volcano erupts, the rock or magma is broken into fine particles, which forms volcanic ash.

Volcanic ash is hard and insoluble in water.

The volcanic ash reaction refers to the reaction of these active components with calcium hydroxide to form reaction products such as calcium silicate hydrate, calcium aluminate hydrate or calcium sulfoaluminate hydrate.

Among them, calcium hydroxide can be derived from the external mixture of lime, or from the calcium hydroxide released during the hydration of cement.

Volcanic ash can be used for building materials.

Lightweight concrete, such as plastering plaster, decorative board filler, is 2% lighter than ordinary concrete, and the refractory is 2% higher.

Block bricks, building slabs, load-bearing components, hydraulic engineering, thermal engineering, bridge engineering building components.

It is used to wash and remove stains, beauty cosmetics, and volcanic ash is also a good thing.

"Father, this thing you call cement is strong and durable. The cost is much lower than that of glutinous rice, soup, egg lake, and charred mud, but there is not much volcanic ash, otherwise it will definitely be popular."

Childe said with some regret.

Cement?

Concrete!

Qingji couldn't help but light up in his eyes.

Childe's worried words just reminded Qingji.

The building materials of this era were dominated by wood, supplemented by earth, and supporting by stone, brick, and tile.

In ancient times, there were two types of soil used for construction: soil in its natural state was called "raw earth", and soil that has been reinforced is called "rammed earth", which is denser than raw earth.

Therefore, the city walls and pedestals of this era were often rammed.

Rammed earth is compacted layer by layer, with a compact structure, and is generally harder than raw soil, while the color of the soil is not as consistent as raw soil.

The most obvious feature is that it can be layered, and the plane between the upper and lower layers, that is, the rammed surface can be seen on the rammed surface, and there are often fine sand particles on the rammed surface.

The outer bread bricks, generally with glutinous rice, egg lakes, soup and other things, add some bamboo strips to stir, a bit like sticky concrete.

Historically, Qin Shi Huang ordered the construction of the Great Wall, which has stood for thousands of years, also because of the use of glutinous rice, a precious material.

Only the king could order the use of glutinous rice for large-scale construction, but it made the people of Li pay serious taxes all year round......

As the saying goes, if you want to get rich and build roads first, the role of cement is very important for Wu Guo.

At the very least, it can reduce costs and strengthen roads.

Cement!

Wu's straight roads, gallop roads, mud roads, wind and rain are easy to damage, brick and stone roads or what egg glutinous rice lake road, the cost is too high, large-scale construction, the cost is huge.

The significance of building a concrete road is heavenly.

Communications, marches, grain routes, trade, etc., in a nutshell, the territory of the ancient Wu State

Limited by the scope of information radiation, too far away for the imperial court to control, and convenient transportation can strengthen the control of the frontier and increase the radiation range of the regime.

In view of this, in the next few days, Qingji mixed with Lu Ban, Ganjiang, Gongzi Wei and others to develop cement.

Qingji has some experience, so he plays the role of a commander.

First of all, Qingji asked people to find a large amount of limestone and clay, grind the limestone and clay into noodles, and then calcined the mature material and then grind it into powder with the slag left after ironmaking.

The prerequisite for this is that the temperature is high enough when firing!

Thanks to the advanced technology of Wu Guoye iron, it has been able to "turn into steel", so it is not difficult to do so.

The fired glass, cement, and steel commonly used in the crossing all needed to be heated at furnaces higher than those of that era.

In the absence of the support of the modern industrial system, Qingji can only increase the temperature by increasing oxygen for combustion and changing fuels.

So the furnace came into being.

Oxygen combustion, that is, blowing air in the stove is very important.

Wu used airbags to blast air in steelmaking, and later invented water drains.

After some mention of Qingji, Lu Ban invented a new type of wooden bellows.

To burn cement, the invention of the bellows is the key.

It is worth mentioning that charcoal was mostly used as fuel in this era, and the furnace temperature could reach 1300 degrees Celsius.

With coal, it can reach 1,800 degrees Celsius.

This is difficult to celebrate.

Where is there a coal mine?

Hedong, Shangdang!

In modern times, Hedong County and Shangdang County of Wu State are Shanxi......

There are countless open-pit coal mines.

After several days of tinkering, Qingji and others finally developed cement.

This is not enough, Qingji knows that cement, or concrete, cannot be used directly, and must be reinforced.

Reinforced concrete can be used for construction.

Because pure concrete, that is, plain concrete, is very easy, very easy to crack, cracking is a characteristic of concrete, so it must be reinforced.

Modern reinforced concrete buildings in Wu Kingdom will definitely not be built, but it is possible to build brick houses with cement.

It is not practical to build concrete dams and high castles with cement, but it is perfectly possible to use them alone to strengthen dams and walls.

"Burn the cement bricks and red bricks."

Qingji gave such an order to the craftsmen again.

As for how to fire it, Qingji didn't know it, so it could only be made by craftsmen through repeated experiments.

Thanks to the Qingji reward for invention, in this year, the craftsmen of the Wu Kingdom also invented spinning wheels, keel waterwheels, matches, and improved trebuchets, which were called "Wu Wang Cannon" (Huihui Cannon).

……

The western suburbs of Xianyang City, Jixia School Palace.

At this time, on the huge square of the Jixia School Palace, a huge debate was underway.

Qingji issued an edict and ordered the court captain Deng Xi and the imperial historian Cheng Bo Tuo to be responsible for recompiling Wu's "Book of Laws", but they did not let them be proficient, or Qingji made his own opinions, but proposed the "sea election", which moved the matter of formulating laws to the table and let the scholars of the world debate.

Then, it will be determined by Deng Xi, Bo Biao and others as appropriate, and finally confirmed by the decision.