In the history of war in Europe, the defensive parties first relied on wooden fences or stone fortresses to defend, but the emergence of catapults and primitive artillery made these two fortifications a decoration. Later, the bastions came into being. For a time, because the shields far exceeded the spear, there were many bastions on the land of Europe and there were many small countries.

European military scientists have persevered in exploring how to solve the trench when artillery technology is not yet fully mature. In the 1770s AD, the French marshal, military engineer, and founder of modern engineers, Sebastian Le Prestre de Vaubon proposed a trench siege system. It effectively solved the important issue of how to take over the trench siege with complete defensive power when attack artillery has limited power.

To put it bluntly, this system means digging trenches, and digging out the trenches system and digging out the art.

The specific excavation method is as follows: first dig a circle far around the target to be attacked, and the digging soil is piled up to the side of the attack target - forming a low wall to protect the engineers on the side. Then, based on this circle of trenches, dig a zigzag trench. After digging to a certain extent, dig a circle of trenches closer to the enemy's city wall. Then start using the cannons or trenches to attack the opponent's city wall or cannons (trenches) on the city wall. If it cannot be done, repeat the above steps until it gradually approaches the opponent's city wall.

In this process, due to the protection of trenches, the enemy troops on the top of the city were basically unable to effectively kill the engineers on the side who were digging the trenches. Similarly, due to the protection of trenches, their siege vehicles, catapults, artillery, etc., moved within the trenches and gradually approached the local city walls.

Moreover, as the trench gradually approaches the enemy's city wall, all the enemy's defense methods on the city wall will be weakened more and more due to angle issues. No matter how strong your city wall is, I have dug up the base of your wall. What other possibilities do you have to struggle?

In the historical plane, in the mid-20th century, Taizu of this dynasty and Kaishengong competed with the Central Plains. The army of the Celestial Empire often used super-strong civil engineering to dismantle the enemy's defenses. This is actually a variant of the Wobon trench system. Therefore, the genes of this dynasty's infrastructure maniac were revealed as early as when the founding of the Guo Foundation.

"This trench system is basically like this, do you understand it?"

"Don't worry, the student has fully understood."

At this time, Guan Yi's favorite disciple Li Xiang and Li Zhanfei had been promoted to the position of General Zhonglang. Although the prefix of this General Zhonglang was an unprecedented "engineering soldier", Li Xiang, who had already become fully mature at this time, no longer had the idea of ​​returning to the combat soldier series before. Because he was deeply fascinated by civil engineering.

"Well, this system needs to be completed quickly, manpower is the foundation. You and your subordinates first survey the soil outside Luoyang City and calculate the project volume. In the middle and late this month, it should be enough for you to give 90,000 prisoners to your teacher, right?"

"Hehe, thank you, the mountain leader. I have never taken care of so many people. But the mountain leader can really bear it. Such a good method has been tolerated until now." After a slander, Li Xiang quickly said seriously: "Don't worry, as long as there is enough food, students dare to guarantee that these prisoners can do things very well."

"Hmph! I am a teacher and I have to endure it until now for a strong city like Luoyang!" After saying this, Guan Yi hugged Li Xiang and whispered: "The secret master of my teacher in the Eastern Wu court sent a reliable message. Sun Hao's idiot was planning to launch an army of more than 100,000 to the north from Nanyang County to lift the siege of Luoyang in August and September this year. Well, although Wu Gou's combat power has never been taken seriously, it was 100,000 people. It was very tiring to cut his head one by one..."

"Students understand. Students will take people to start doing things right away."

My boss and teacher have already set the completion time for me, so what else can I say? Get up quickly.

...

Starting from March 20 of this year, more than 90,000 prisoners of Jin State under the control of the Han army came to the outside of Luoyang City one after another.

On April 1, Li Xiang, who had completed geological exploration and drawing design, with the help of many lieutenants and military marquis under his command, completed the assignment of more than 90,000 prisoners of war. Then, with the order of the general of the engineer, more than 90,000 prisoners of war were launched together. The trenches began to be dug 500 meters away from the outer wall of Luoyang.

In front of these prisoners of war, nearly 100,000 Han troops formed an array to protect and monitor the staff.

Five hundred meters have exceeded the maximum range of the trench and bows at the top of Luoyang City. Therefore, in the face of this move of the Han army, the soldiers and civilians in Luoyang City can only watch except to watch.

"What is Han Dynasty doing?"

"Is it necessary to dig the tunnel?"

"But how could it be so obvious to dig tunnels? No, huge..."

Not to mention Du Yu, Ma Long and others have no knowledge, they have caused a lot of trouble to time travelers. Unfortunately, this is a gap in the times rather than a problem of personal abilities.

Besides, now they have been deprived of military power and become idle decorations that they don’t care about.

Yes, it was the enemy's troops at the end of the city, so at this time Sima Yan once again removed the military power of all generals of the other surnames. All the troops were led by the Sima family.

The defensive leadership organizations in Luoyang City are now as follows:

Commander-in-chief of the city defense: Emperor Sima Yan, personally led 20,000 princely guards.

Executive Commander-in-Chief: Marshal of the World, Director of Military Law, Sima You, King of Qi (responsible for being a villain, such as punishing a prince with ineffective defense or something)

Deputy Commander-in-Chief: General of the State of the Assistance, Sima Jun, King of Ruyin, General of the State of the State of the State, Sima Gui, King of Taiyuan (each commander of 10,000 troops as reserve soldiers)

The person in charge of the city gate: the nine Simas led by King Sima Lun of Zhao... each led more than 14,000 soldiers and five or six thousand civilians to form a team of nine twenty thousand people, responsible for defending the nine gates of Luoyang.

Beyond these thirteen Simas, the only two have real power:

First, the chariot and cavalry general Jia Chong and Jia Gonglu's responsibilities are: to mobilize all the personnel in Cao to conduct strict monitoring of all the officials and people in the city to prevent these people from cooperating with the outside enemies. Among them, the key monitoring targets are: Shangshu Ling Pei Xiu.

Second, Shangshu Pushe Yang Gui: Responsible for the management and distribution of logistics supplies.

This is normal and reasonable. It just completely hurts the hearts of a group of foreign generals. If this battle is defeated, these guys will willingly surrender to Ji Han. If it wins, well, if it wins, you will win. Let the people of the Sima family do the task of regaining the lost land in the future.

Besides, in the hearts of Du Yu, Ma Long and others, they were in awe of Jiang Wei: because in this world, no one has ever won against Jiang Wei with equal military strength. But they have some ways to make Jiang Wei return in vain.

As for Guan Yi, he was completely desperate. Because this guy didn't have any beauty when he was stupid in the war. However, if he counted the battles he commanded, he was increasingly inclined to defeat the Wei and Jin dynasties in the way that Wei and Jin were best at: logistics crushing.

Du Yu, who was standing on the top of the city, looked at the prisoners who were digging trenches under the city for a long time, and used a color to Yang Hu. Yang Hu lowered his head and drooped his ears, and only heard Du Yu say softly: "Why do I think that Emperor Xuan's descendants will eventually die in Emperor Xuan's military tactics."
Chapter completed!