Daqin Engineering Corps

Therefore, Ye Changmengduo should make a quick decision.

But what can be done in this situation?

The first and second paragraphs are good to say, the Qin army organized tens of thousands of people to clear the silt, and it could be completed in three to five days.

But the third section under Daliang City... let alone three or five days, whether it can be cleared in three or fifty days is a question.

Shen Bing, who has been silent all this time, made a suggestion:

"Can the first two sections be desilted and the third section be built with dams?"

This is actually quite understandable.

If there is silt blocking the river course and causing the river to overflow to the side, then use dikes to block it on both sides.

In fact, there is no need to block the "both sides", because the other side is Daliang City, that is, it is only necessary to block the side away from Daliang City.

But how could Zheng Guo not think of such a simple question.

Zheng Guo replied:

"Building a dam may be feasible."

"But the dam still needs to be built under Daliang City, and it will take longer. Isn't it worth the loss?"

That's what it says.

You must know that the range of crossbows in this era is more than a hundred steps, and the range of trebuchets can even reach two hundred steps.

It is true that there is no need to go directly to Daliang City to build a dam, but it is not far away.

If the dam is built far away, like a hundred steps away, and worried that the water will not be enough to pose a threat to Daliang City...

So when you come and go, you still have to work under the blow of Wei Jun's bow and crossbow, which is not much better than digging river mud to dredge.

Shen Bing had a question that he didn't understand, so he asked curiously:

"Why does it take longer to build a dam?"

Yang Duanhe and Zheng Guo cast strange glances at Shen Bing at the same time.

Isn't it common knowledge that building dams takes longer?

But it turns out that there are two common methods of building dams in this era:

One is to build stones along the river bank.

The other is to fill with wood and rammed earth, and then compact it.

Otherwise, if the soil is too loose, the river will collapse as soon as it is flushed.

And neither of these two dam building methods is fuel-efficient.

Laying stones?This involves the problem of moving stone and laying solid.

Timber rammed earth?Pounding both logs and rammed earth takes time.

It would be fine if you did it in other places, but doing it under the range of the Wei soldiers' crossbows... is undoubtedly fatal.

So as Zheng Guo said, doing this is more difficult and troublesome than dredging mud.

Shen Bing asked suspiciously:

"Why don't I fill in a makeshift embankment with sandbags?"

"Anyway, this dam doesn't need to take long, it only needs to flood the girder with water for a few days!"

Zheng Tong couldn't help but wonder:

"Sandbags? What are sandbags?"

Shen Bing secretly thought that there were no sandbags in this era, so he explained:

"It's actually a sack."

"Fill it with sand and call it a sandbag!"

Yang Duanhe was dumbfounded when he heard that.

Zheng Guo said "oh", widened his eyes and said:

"Is it 'grass wrapped in mud'?"

"The stingy man is saying... 'Grass Wrapped Mud' made of sacks?"

"good idea!"

It turns out that there were no sandbags in ancient times, but that everything in this period was artificial, even the hemp ropes were twisted one by one, and the sacks were woven by hand.

It is usually used for grain, such as the transportation of military rations, which requires many sacks.

It is difficult to make and the output is small, so of course it will not be filled with sand and thrown into the river...it will become an insignificant piece of temporary embankment.

The method commonly used by the ancients to block water is what Zheng Guo called "grass wrapped in mud".

It uses reed grass, thatch or wheat stalks to wrap the clay into a cylindrical shape, and then tie it with hemp rope to make sandbags.

The advantage of this kind of sandbag is that it does not need to use gunny bags, so it is very cheap. The disadvantage is that the water blocking effect is not good and it is affected by seasons and regions.

For example, it is difficult to fill it with stones or sand without leaking, and it is still easily washed away by water.

Another example is that there are fewer reeds and thatch in winter, and most of the wheat stalks are burned when they are in the fields. At this time, it is not easy to find a large number of raw materials to make, and it also requires a lot of manpower and time-consuming to make.

So it's not that Zheng Guo didn't think of this method, but that this method can't be used and can't be used.

At this time, when Shen Bing said sacks, he couldn't help but nodded slowly.

Yang Duanhe asked curiously:

"According to the miser, can these sandbags be used to build temporary dams?"

"And can it be done in a short time?"

In order to explain better, Shen Bing simply ordered someone to fetch dozens of sacks for a demonstration.

While commanding the craftsmen to work, Shen Bing said:

"I can fill the sack with sand first."

"What kind of sand to fill depends on the situation."

"For example, near the outer edge of the river, sand and gravel that are not easy to disperse in the water can be used."

"The inner edge uses more stable rammed earth."

"After filling it up, tie the bag tightly, and stack the embankment staggered at the place where the embankment needs to be built!"

As he spoke, the craftsmen stacked dozens of sandbags and lined them up, forming a dam in a short while.

After finishing, Shen Bing added another sentence:

"If you add wooden stakes and hemp ropes to tie it up, it will be even stronger!"

Yang Duanhe looked at Zheng Guo, as if asking Zheng Guo whether this method is feasible.

Zheng Guo nodded affirmatively and replied:

"This method works, this method works."

"This sandbag is similar to 'grass wrapped in mud', but I don't know how many times better than 'grass wrapped in mud'!"

"The sack can firmly gather sand and stones together without loosening. Although the water blocking effect is not as good as that of a dam, it is not weak."

"Unless the sacks are rotten and cracked due to long-term soaking in water, this dam..."

After thinking about it, Zheng Guo said again:

"Why don't I try it?"

Yang Duanhe asked:

"What kind of trial?"

In fact, you can really try.

Zheng Guo found a ditch with a moderate flow of water. There are ditches like this everywhere in Wei Guo.

The reason why "the water flow is not urgent" is because the water flow will become more and more urgent when the water is blocked, and it can probably reach the level of flooding the girder.

Then, just like what Shen Bing said:

First drive piles in the ditch, and then fill sandbags between the piles... As the sandbags are filled one by one, the water flow in the ditch is blocked after a short while.

Then continue to fill some sandbags behind the wooden piles for reinforcement, and a dam stands in front of everyone.

Zheng Guo looked at Shen Bing and sighed:

"The coward's method is very good for blocking water."

"It is fast and effective. Although it consumes a lot of sacks, it is not a problem in an emergency."

That's what it says.

No matter how important the sack is, it will not be more important than destroying Wei, right?No matter how expensive it is, it won't be more expensive than Daliang City, right?

And military emergency time is everything.

Just because you can't use sacks usually doesn't mean you can't use them at critical moments.

Especially when there is no other way to go.

So Yang Duanhe no longer hesitated, and immediately ordered:

"Transfer sacks from Handan immediately!"

"The more the better!"

135章 红烧

Under the command of Zheng Guo, the dredging and blocking work was carried out step by step.

To be precise, it should be dredging and embankment, because it is divided into two parts, one is dredging and the other is embankment.

The highly technical matter of dredging was mainly directed by Zheng Guo.

Shen Bing was responsible for embankment construction.

In fact, Zheng Guona did not start to clean up from the Guangwu Jiankou as previously planned.

This is because Zheng Guo considered that dredging would be more troublesome if the Bian River had river water... the water was flowing, and the dredging soldiers had to row a boat and use a long pole with a hoe to reach the bottom of the river and dig bit by bit.

This excavation method may not be able to complete the dredging even if it is dug for a month.

So Zheng Guo decided to stop the flow first.

That is to block the mouth of the Yellow River and make the Bian River dry.

Once the river dries up and clears the silt, it will be much more convenient... Soldiers can directly dig into the river with short hoes and carrot baskets, and soon baskets of river mud will be passed down and then transported to the fields by horse-drawn carts for dumping.

The reason for dumping it in the field is that if it is dumped nearby, it is worried that the river mud will be washed into the river when the river rises, and the result will be a waste of work.

On the other hand, it is the "war to destroy the country" that Shen Bing said before.

Since the country is going to be destroyed, the fields of Wei State will belong to Qin State in the future, why not think about the fertility and harvest of the field in advance?

That black river mud is a good fertilizer!

But it wasn't these things that excited the soldiers of the Qin Army even more.

As soon as the river dries up, there are jumping river fish everywhere in the river.

Perhaps Yang Duanhe wanted to reward the soldiers, and at the same time, in order to supplement the army rations, he specially allowed half an hour for the construction soldiers to fish.

That scene was lively, like a good harvest, soldiers everywhere were crawling and running in the river mud, catching baskets of river fish...

The river fish in this period were really big, with each tail as thick as an arm.

Shen Bing thought that this might be related to the undeveloped fishing technology in this era.The technology is underdeveloped, so the fish have a longer survival time, so they are generally bigger.

In modern times, when an electric fishing rod is inserted into the water, all the fish will surface on their stomachs, and even fish as big as a little finger will be electrocuted to death.

That night, the soldiers of the Qin Army ate a delicious meal of river fish.

Of course, Shen Bing showed off his culinary skills again at this time.