Wu Yanzhi looked closely, this picture is almost like a painting, not only does it not have a regular proportion, but there is no saying of "up north and down south, left west and right east".

The drawings of my previous life, from the stacked drawings (A4 paper size), to the line thickness of the drawings and the representation of the drawings, are all national standards, and they can't be messed around.

The most basic drawing is the "three views", and most people who are engaged in engineering have to learn that the three views can not be sloppy at all! He learned cartography well when he was in college.

Wu Yanzhi was about to take a closer look at the picture, but Zhang Dajiang pointed to a senior official in scarlet clothes and introduced: "Wu Lang, this is Wang Zhiguan.

Wang Zhiguan is the governor of Puzhou, and has been serving as a general as a direct official for more than 30 years, and his specialty is building bridges! This Fengchi Bridge was designed by Wang Zhiguan! ”

The two saluted each other.

Then Wang Zhiguan introduced the Fengchi Bridge to Wu Yanzhi and others: "We have determined the height of this bridge according to the water level records of Luoshui and Gushui in the past few decades.

The bridge is a three-arch stone bridge with a large arch in the middle spanning the valley, with a width of 92 feet and an arch height of 42 feet. The two small arches next to it should be ten feet high, mainly to facilitate the arrival of floods, and to discharge the flood ......"

Although the drawing he drew was very simple, from what Wu Yanzhi introduced, this Wang Zhiguan was indeed very proficient in building stone arch bridges.

This bridge is three meters taller than the other three highest bridges next to Shangyang Palace, with a width of 15 meters and a length of 102 meters.

However, he does not describe much about the pedestals on both sides of the bridge, especially the abutment that connects the Shintoen to the west.

Although Wu Yanzhi is not a bridge major, many theories of engineering are the same.

Since the terrain of Shintoen in the west is also relatively flat, floods can easily inundate the roadbed, and it will be difficult for people to retreat at that time.

After Wang Zhiguan introduced the plan, Zhang Dajiang asked Wu Yanzhi to give his opinion.

Wu Yanzhi nodded and said, "Wang Zhiguan's bridge is indeed well designed, and the amount of flood discharge has been fully considered!" ”

Hearing this, Wang Zhiguan was very happy, and the people around him also began to congratulate him.

In their opinion, Wu Yanzhi, a young man who is proud of the spring breeze, and the prince of the county, just relied on his royal status to ascend to a high position, where can he have any real talent and learning? It must be a simple compliment.

Wu Yanyi looked at it and shook his head secretly, I haven't finished talking yet, I thought to myself, it is impossible to find out the fault from the mechanical structure.

The main reason is that I don't study bridges, and I don't know how to analyze the mechanics of bridges.

Moreover, these people are very experienced in erecting stone arch bridges, much stronger than themselves, and they will definitely not collapse easily.

However, there are still a few issues that need to be clarified. So he said: "However, I still have a few suggestions to put forward to Wang Zhiguan.

First, the stone slabs on the bridge deck need to be replaced. I suggested switching to my newly developed cement-blended concrete to minimize bumps.

You haven't seen the concrete, it's used to pave the road, and after it's smoothed, it's smoother than the common Sanhe soil like you.

In the future, if the saint wants to enter the Shendu Garden to hunt, enjoy the flowers, and escape the heat, he will also avoid unnecessary bumps.

Secondly, the height of the west bridge abutment and subgrade section should be increased by another five or six feet, that is, it should not be lower than this bridge deck.

I suggest that the bridge deck be made flat, so as to resist the flood that hit Shangyang Palace. Otherwise, if both ends of the bridge are flooded, it is useless to not be able to get on the bridge.

Third, the flood control measures of the west roadbed are not in place, in my opinion, if the west roadbed is not treated with flood control measures, this high roadbed is easy to be washed away by floods.

If the roadbed is washed over and the road is flooded, the bridge is also useless. I've seen the site, why don't I dig a small flood canal, cross the west embankment, and build a small bridge over it! to reduce the erosion of the roadbed by flooding.

At the same time, the section of the more than 200-foot-long high roadbed must be reinforced with masonry! It is necessary to build this bridge into a thousand-year-old bridge and a thousand-year-old bridge!

Also, Wang Zhiguan must know about Zhaozhou Bridge, right? This bridge is best designed according to the plan of the bridge, and it is more convenient to sail in the river! ”

After Wu Yanzhi finished his thoughts, the Wang Zhiguan couldn't help but nod his head again and again: "I didn't expect Wu Langzhong to be so familiar with the bridge, and he also knew the Zhaozhou Bridge, and he was taught."

Indeed, as Wu Lang said, if the purpose of this bridge is to facilitate the people in Shangyang Palace to escape when the flood comes, then there are some problems with the current design! This design is also mainly about cost savings! ”

Of course, Wang Zhiguan knew about the Zhaozhou Bridge, but he felt that his understanding of the bridge was not thorough enough, so he did not adopt the plan.

"Bridges are big deals, don't care about spending a few pennies more, but care about their safety and practicality. I hope that in a thousand years, this phoenix bridge will still stand here! On the pier, Wang Zhiguan's name is still engraved on it! "The Way of Martial Flame!

Zhang Dajiang nodded again and again when he heard this, and said to Wang Zhiguan: "I think Wu Langzhong's words are extremely reasonable, and this project cannot be sloppy." In case of a once-in-a-century flood that floods this Shangyang Palace, and the people inside can't get out, I'm afraid that we will destroy the five clans.

Wang Zhiguan, you should revise it according to Wu Langzhong's opinions, and you must discuss it with Zhang Zhiguan, Liu Zhiguan and others to ensure that the plan is foolproof! ”

Wu Yanyi listened to it, his own is a "suggestion", not an "opinion", which is different. This master Zhang changed his opinion, meaning that he had to do it!

After that, the group studied the buildings and greenery on both sides of the bridge.

After the meeting, Zhang Dajiang asked Wu Yanzhi to inspect the maintenance project of the north side of the palace city and the warehouse tomorrow.

Wu Yanzhi agreed, he had long wanted to see what the first granary of the Great Zhou was like.

……

On the second day, after Wu Yanzhi finished his work in the division, he came directly to Hanjiamen, the south gate of Hanjiacang City. Repairs are underway here for two storehouses where grain was stored, as well as repairs to the northern wall.

Wu Yanzhi read the relevant information about Han Jiacang in the winter lawsuit.

Hanjiacang, also known as Hanjiacang City, is "the first granary in the world". It is 410 steps (615 meters) wide from east to west, 475 steps (713) meters long from north to south, with a total area of more than 430,000 square meters, which is an important part of Luoyang City, the eastern capital of Sui and Tang Dynasties.

According to the data he heard from the court meeting, at present, there are more than 7.6 million stones of grain stored in the warehouses of the entire Great Zhou, including 4 million stones in Jiacang City, which is more than 50%, which is indeed worthy of the "first granary in the world".

Wu Zetian had lived in Luoyang for a long time, including Emperor Yang of Sui, and also liked Luoyang. It's not that Luoyang is better than Chang'an, in fact, Luoyang has no danger to defend, and it is not conducive to building a city.

It's just that Luoyang has one of the biggest advantages compared with Chang'an: there is no shortage of food!

Because the grain from Jiangnan and Hebei is transported to Luoyang through the canal, relatively speaking, it is relatively easy! But to get to Chang'an, you have to go through the Sanmenxia of the Yellow River, which is very difficult.

Because of the large population in Guanzhong at that time, the yield per mu was low at that time, and the yield per mu of dry land was a little more than one stone (about 120 city catties); Rice is about two stones, three or four buckets (about 250 catties).

This self-produced grain is far from satisfying the needs, because there are more than one million officials, soldiers, and ordinary people in Chang'an alone, and a large amount of grain has to be transported through the Yellow River!

Wu Zetian has lived in Luoyang for a long time, and he will definitely take away hundreds of officials and their families, guards and soldiers, etc., these people together are at least 10-150,000 people!

According to the calculation of 7.2 stone of grain per year determined by the imperial court at that time, these people will consume grain a year: 720,000 stone ~ 1.08 million stone! An average of 900,000 stone a year is a must.

Therefore, in Luoyang Dingdu, it is of great help to reduce the food pressure in Guanzhong.