Chang Yuchun turned to Lao Zhu and said respectfully: "Xuanzhong is too young, I'm afraid I can't afford the errand of building the city wall, and the emperor should choose another talent as soon as possible." ”

Ma Du smiled bitterly, knowing that the two had misunderstood, he hurriedly explained, "The emperor and Chang Gong don't know, these planks are just molds for pouring, and the young son and the linen cloth are just to prevent the mud inside from leaking out." ”

Lao Zhu snorted inside his nose, "It's really muddy!" ”

It seemed that he couldn't explain it clearly to Lao Zhu, so he simply spoke with the facts, and Ma Du hurriedly got someone to take down those planks, who knew that Lao Zhu's face was even more ugly.

The slag of the gray city wall soil is far less deep and heavy than the blue bricks, and there are a lot of fragments of oil paper and rags stuck to it, and there are some traces of pebbles, which looks like a big flower face.

What made Lao Zhu most angry was that the six-zhang city wall was divided into three sections, and there was a gap of about three inches between each section, he was really annoyed, and the kung fu of the poisonous tongue was also exerted to the extreme at this moment, "Why don't you leave this gap a little bigger, it's not better to let the enemy get in directly." ”

Chang Yuchun originally helped Ma Du, but at this moment he couldn't help but complain, "Xuanzhong, why don't you build a nun wall after you build a city wall, do you let the soldiers be the target of arrows on it." ”

"I really forgot to repair the women's wall, as for this gap, Weichen deliberately left it for the convenience of repairing it in the future." Although Madu did not study architecture, he was not stupid enough to cast the city wall into a huge whole. This is not only inconvenient but also increases the risk, and it is not certain that there will be any unstable stress inside that will cause cracking, and segmented construction is the most suitable.

Old Zhu snorted angrily and said, "Is there a future?" I think it's just a pile of tofu dregs! He casually took out Han Cheng's waist knife, and shot directly at the city wall with a forceful flick, but the result was not the scene he imagined to cut tofu.

When the steel knife and the city wall contacted, but burst out a string of sparks, it can be seen that Lao Zhu's strength is great, and then saw the steel knife fall to the ground with a bang, Lao Zhu was dumbfounded at the moment, he walked to the edge of the city wall, personally picked up the waist knife and found that it had been rolled up.

He snorted, and slashed his knife at the city wall again, only to feel as if it had been slashed on a stone, and there was only a shallow trace on the wall, and he found several different places and slashed several times in a row. He stretched out his big rough hand and touched the wall, only to feel cold and solid, really like stone.

Lao Zhu immediately ordered: "Han Cheng hurry up and get some firearms from the Firearms Bureau, the more powerful the better!" ”

Grenades, guns, and tiger squat cannons took turns to go into battle, and Lao Zhu simply transferred a few guns with the largest caliber to fire solid shells, and several rounds of artillery came down to hit the sand and stones, and the city wall was full of large dents at the mouth of the bowl, but the main body was still intact.

Ma Du watched coldly from the sidelines, and finally understood that Lao Zhu couldn't trust him, and he clearly came to slap him in the face, and he was very unhappy. Lao Zhu was like a chameleon, and said with a smile: "Xuanzhong really lived up to my expectations, I have long said that Xuanzhong will definitely do the errand properly, Boren, you still don't believe that he has to quit his errand, I am fortunate that I didn't listen to you." ”

What a shame! This is Ma Du and Chang Yuchun's truest thoughts at the moment, Chang Yuchun arched his hand and said: "It's Weichen's clumsiness, this city wall looks inconspicuous, I didn't expect it to be so strong, or Xuanzhong has the ability!" ”

Lao Zhu patted Ma Du's shoulder vigorously, "My brother-in-law is naturally not ordinary, this city wall is not only strong and fast, but one hundred and ten craftsmen can build six zhang in four days." ”

Ma Du rubbed his shoulder, which was about to be slapped away by Lao Zhu, "It's not as fast as the emperor said, there is a lot of preparation work ahead, four days is just the last process, and the manpower used is far more than that, there are more than 200 people who transport mud with mud alone, and those more than 100 are just pouring manpower." Carefully calculated, this is probably more than 300 people built in more than ten days. ”

Lao Zhu nodded, "That's already very fast, by the way, what's going on with those muds, how did they get hard?" ”

Ma Du understood why Lao Zhu came with a posture of asking for guilt, it seemed that his every move was under his surveillance, and he heard that he used mud to build the city wall, and estimated that his Tianling Gai was about to be overturned by anger.

"Weichen calls that kind of mud cement, which is usually just loose powder, but it lives into mud with sand and pebbles, and when it dries, it will become as hard as a stone, of course, it is still a lot worse than stone, but it is definitely more than a star and a half stronger than ordinary green bricks.

The mixed steel bars are poured into such large blocks, and it is even more difficult to break them, and Wechen calls this kind of building structure a reinforced concrete structure. By the way, cement also has a special use, which can replace glutinous rice as a binder between masonry and stone, and the effect is better. ”

"Seriously! Ha ha...... At this time, the construction of city walls in various parts of the Ming Dynasty will save a lot of food. Lao Zhu laughed for a while and asked, "What kind of steel-concrete structure are you talking about, is it more durable than ordinary masonry?" ”

Ma Du replied, "It's a reinforced concrete structure, it can be used for at least a hundred years, and it may have to be partially repaired at that time, which is why Wechen poured it in sections." ”

Nanjing's city wall is more than 600 years standing, but it is a prosperous and rich city, in these 600 years is constantly repaired, to see the city wall of Nanjing, you know that there are many city bricks without the names of officials and craftsmen, should be replaced when repairing later.

"Hmm." Lao Zhu nodded, "Then how much does this kind of reinforced concrete cost?" ”

Ma Du had already prepared, he took out the account book and handed it to Lao Zhu's hands, these were sorted out by the students, Lao Zhu took it over and looked through the pages one by one, he actually liked to read the things that Ma Du handed in, no nonsense and organized, such as the account book in front of him, drawing charts, even if he had not learned, he could understand it at a glance.

Lao Zhu kept turning to the last page, glared and asked, "Is it just spending this money?" ”

Madu nodded, "Yes! This includes the cost of developing cement in the early stage, as well as the wages of craftsmen, while the craftsmen allocated by the emperor do not use labor. ”

"Good! Xuanzhong, I'll leave this errand to you! Lao Zhu looked at the gray city wall again, "It's just that this city wall is too ugly, there is no big country weather, it is better to wrap a layer of green bricks outside, and start construction after the autumn harvest." "After all, I can't escape the kind of carved green bricks, but with reinforced concrete as the main body, you can save a lot.

"The emperor Weichen thinks that this city wall is not in a hurry to repair, this cement is a new material, it is better to let this reinforced concrete city wall experience another year of scorching heat and cold, wind and rain, if there is no problem, it is not too late to build it!"

Lao Zhu said in a trusting tone, "Even the cannon stone can be restrained and I am afraid of the wind and rain, although Xuan Zhong can let it go!" ”

Madu asked tentatively, "Then what if something goes wrong?" ”

"Humph! Needless to say, naturally I'm looking for you, anyway, if you have the money, I'll rebuild it when the time comes! ”