"Big Head must be joking with Dad." Nie Tianqin was not in a hurry at all.

Looking at Nie Tianqin's determination, Nie Guangyi pulled the corners of his mouth and smiled, and deliberately asked, "How can you see it?" ”

"Father's intuition." Nie Tianqin did not shy away from it.

"That's it?" Nie Guangyi was obviously not very satisfied with this answer.

"Because my son is a genius and has a great memory since he was a child, it is absolutely impossible for him to forget the things he remembers." Nie Tianqin changed his words.

"Hmm." Nie Guangyi nodded with satisfaction and said, "Professor Nie is reasonable. ”

"Big head, tell your dad how to do it once and for all."

Nie Guangyi no longer twisted: "For ancient buildings, the biggest hazard is fire. Whether it is Yuqing Bridge, Baixiang Bridge or the ancient villages in Yunnan, they were all destroyed by fire. Let's not talk about the ancient villages and the wooden bridges that are still in use, let's focus on Wan'an Bridge. What exactly are we going to pass on? ”

"Of course, it's the traditional construction technique of wooden arch bridges, especially the woven wooden arcade bridges."

"Well, then, this bridge is no longer there, let's rebuild it, in addition to the art itself, shouldn't we also keep this bridge away from the fate of being destroyed every fifty to hundred years?"

"It will definitely be in the area of security, and it will be more in place than before." Nie Tianqin paused, "Although Dad can't personally participate in the reconstruction of Wan'an Bridge, the regulations for supervising and supervising fire prevention are definitely still possible." ”

"I don't think that's enough." Nie Guangyi's tone was firm: "The reason why an accident is an accident is because it is inevitable. ”

"What is the opinion of the big head?"

"Before rebuilding the Wan'an Bridge, we should first study high-tech flame retardant materials." Nie Guangyi said.

"Rebuilding the Wan'an Bridge with high-tech materials? I'm afraid that's not right, right? Nie Tianqin disagreed: "If these bridges had been changed to reinforced concrete earlier, they would indeed not have been burned, and this skill would have been lost." ”

"Why can't you understand such a big professor?" Nie Guangyi said with a smile.

"Dad is old, big head tell dad about it." Nie Tianqin smiled happily.

What is wrong with admitting his son to his face?

"The high-tech flame retardant material I am talking about is directly added to the wood, so that the wood itself becomes a flame retardant material, not concrete or steel structure."

"You say this, this has been there since ancient times." Nie Tianqin gave an example: "In the 4th century BC, the ancient Romans had already discovered that soaking wood with vinegar and alum solution could produce certain flame retardant properties. ”

"Isn't this right, Professor Nie, in addition to ancient Rome, the four major ancient civilizations have all used similar methods to improve the flame retardant performance of wood, whether it is seawater or alum, they all have their own methods, and these wisdom that has existed since ancient times can also be counted as intangible cultural heritage, right?"

"That's right." Nie Tianqin's words changed: "But history has also proved that there is no such thing as a one-and-done one-and-done. ”

"That's because technology isn't advanced enough." Nie Guangyi briefly summarized: "These primitive flame retardant methods continued until the 16th century. With the development of science and technology, there are slowly patented flame retardants. By the time of the first industrial revolution, wood flame retardant had become a professional industrial technology. Later, the two world wars promoted the rapid development of the flame retardant industry, and composite flame retardants began to exist. ”

"The big head is right. But composite flame retardants don't solve the underlying problem, do they? ”

"Yes, that's why we need more high-tech blessings. The flame retardant used in the aerospace industry today will also be used in life in the future. ”

"It will take a long time for flame retardants in the aerospace industry to be used daily."

"It's not going to be a long time coming, and the investment in the aerospace industry is so large, isn't it just for the leapfrog development of industry?"

"Daddy believes you, big head, you tell me in detail about the one you just mentioned." Nie Tianqin almost took out his notebook and recorded it.

"First, when we are rebuilding, we must do a good job of fire protection planning."

"That's for sure." Nie Tianqin replied: "Eat a trench and grow wisdom." ”

"Second, wood cannot be completely flame retardant, we can only use technology to extend the time for the water in the wood to evaporate and finally decompose and burn."

"How do you get through technology?" Nie Tianqin asked.

"There are several aspects to this."

"Okay, Dad, listen to your analysis slowly."

"The first is the choice of wood. The construction of Wan'an Bridge began at the earliest, and it must have been made of local materials. ”

"Yes, at that time, the natural conditions were relatively limited, and the local roads were all mountain roads, with the capacity level of the Song Dynasty, there was definitely no possibility of long-distance transportation of timber, and there was no need for this."

"Yes. At this time and then, we think that from the perspective of cultural relics created in future generations, we can abandon the principle of local material selection. ”

"Purpose?"

"The goal is simple, to give preference to wood that is not easy to burn in the first place." Nie Guangyi further gave an example: "For example, the sea pine in Hainan. ”

"Sea pine? Has Datou studied the properties of sea pine other than flame retardant? ”

"Nope."

"Big head, the choice of wood, first of all, needs to have a functional consideration."

"What kind of functionality?" Nie Guangyi asked out loud.

"Not all timber is suitable for wooden arch bridges." Nie Tianqin gave an answer.

"Of course I know this, and it must be on the premise of ensuring the use of the wooden arch bridge. Sea pine is just used as an example, it does not mean that you should choose sea pine. If you are not a sea pine, you can also have other options. We can even source suitable timber from all over the world. ”

"Looking for timber all over the world, is that still Wan'an Bridge?" Nie Tianqin never thought about the possibility of global material selection.

"Professor Nie, I'm going to talk about you, Wan'an Bridge is the first batch to be included in the UNESCO List of Intangible Cultural Heritage in Need of Urgent Safeguarding, which is originally the heritage of mankind. You have to limit the source of wood, will your horizons be a little unbroad? ”

"Why did it get a personal attack all at once?"

"How? Didn't you arrange for a blonde German student to come and wreak havoc on my office? ”

"Woe to you? The Ph.D. I brought with me, even in your office, is still outstanding. ”

"It's easy to say, it's easy to say." Nie Guangyi smiled.

"What to say, big head, you don't want to be cheap and behave. When I didn't come to Padua before, my father didn't know the specific situation, and after I came, your whole office was basically in charge of it. ”

"Okay! Our Professor Nie is full of peach and plum all over the world, and all of them are the essence. ”

"Why do you call people essences?"

"Elite, elite, right?"

"That's pretty much it!"

"How do you react to your student more than your son?"

"That's when you haven't seen people talk about my son, what was my reaction!"

"You can pull it down, your son is such a big genius, what is there to be said?"

"That's a lot!"

"For example?"

"For example, one or two asked me when my son would bring me a grandson."

"Which grandson is so nosy?"

"Big head! You can't talk like that. It must be the elders who would talk to my father about such things. ”

"Okay, okay, okay, I won't tell you this." Nie Guangyi diverted the topic again: "Let me ask you, if your subordinate Dr. Frederick wants to learn mortise and tenon structure and beam structure, do you teach it or not?" ”

"Of course it's teaching. Friedrich also gave himself a Chinese name, called Fedek. ”

"Why didn't he just call Federer?"

"That doesn't sound like his name. Nowadays, international students should choose their own Chinese names, and they must have both form and spirit. ”

"And what about the second aspect?"

"The second aspect is high-tech flame retardants. Even if flame-retardant wood has been used, it still needs to be blessed with scientific and technological flame retardants. We need to calculate a maximum fire response time. ”

"Longest fire response time?"

"It's how long it takes for firefighters to arrive at the scene in extreme cases. We need to use the wood itself and the new composite flame retardant and even the aerospace flame retardant to make the rebuilt Wan'an Bridge able to survive until the time when it is rescued. It even has a direct self-help function. ”

"Directly save yourself?"

"Wan'an Bridge was built on water. We wanted to preserve the traditional construction techniques of the wooden arch bridge, so as not to affect our use of the stream water and build an automatic fire protection system. ”

"What kind of automatic fire protection system?"

"It's just that in the event of a fire, spray water directly on the Wan'an Bridge. Whether it is a hotel or an office building, don't all rooms have automatic sprinkling functions? This is already a very daily function, why can't it be used on Wan'an Bridge? ”

Nie Tianqin fell into deep thought.

"Professor Nie, are you worried that this will destroy the original structure of Wan'an Bridge? There is no need to worry about this at all, we are building automatic fire-fighting facilities under the bridge and into the water, and we are not adding anything to the Wan'an Bridge. ”

"Daddy isn't worrying about this?"

"So you think this fire protection system is a foreign product? Does it not comply with the "Operating Regulations for the Maintenance and Maintenance of Ancient Buildings" that you participated in the revision? ”

"It's not."

"What's that, Professor Nie?"

"Dad couldn't tell for a while."

"Professor Nie, intangible cultural heritage is the heritage of all mankind, and if we want to rebuild it, we must ensure that the rebuilt Wan'an Bridge will not be destroyed every half century. Learn from each other's strengths, foreign for Chinese use, all kinds of measures, as long as these wooden arch bridges no longer suffer from reincarnation, are meaningful. ”

"Datou, you are right, whether it is the traditional construction skills of wooden arch bridges or the construction skills of Dong wooden buildings, as long as the traditional construction skills are still preserved, the style and style of traditional buildings will not be lost."

"Professor Nie, how is Wan'an Bridge going to be rebuilt? Are we going to restore the Wan'an Bridge to its original appearance, or will it be the same as the one that just burned down? ”

"What do you think?" Nie Tianqin wanted to hear his son's opinion first.

"If it's possible, I naturally hope that it will be restored to the way it was when it was first built in the Song Dynasty."

"There are not many historical records about Wan'an Bridge, and it is difficult for us to know what Wan'an Bridge looked like in the Song Dynasty. The name Wan'an Bridge is only the same age as your Grandpa Qiu, and it is not called Wan'an Bridge in the future. ”

"Professor Nie, what you mean by this is that I hope that Wan'an Bridge will return to the way it was when it was burned down for the last time."

"Not really, the rebuilding plan of Wan'an Bridge has not yet been decided."

"I'm not asking about a plan, it's what you really think in your heart."

"Daddy and you think the same thing. If it can be restored to the way it was in the earliest days, it will definitely be more historical. But this also means that the memories of the growth of the people of Changqiao Village under the witness of Wan'an Bridge will be slowly erased. ”

"Professor Nie, have you ever thought about it, even if it can be successfully restored in full accordance with the traditional construction skills of the wooden arch bridge, the historical value of Wan'an Bridge will be difficult to recover."

"Yes, we in academia have always had such controversies. Whether the destroyed ancient buildings can be restored in the true sense has been debated. ”

"Theseus' ship paradox, isn't it?"

"Dad thinks this is a more debatable question than the paradox of the ship of Theseus."

"Why?"

"The ship of Theseus is at least the same craft of the same era of craftsmanship, and although the planks on the ship have been changed, they are all the same craft. This is still very different from the situation of Wan'an Bridge. ”

"To be specific?" Nie Guangyi asked.

"The actual situation now is that the manual era has been replaced by industrialization, whether it is tools, the environment, or the craftsmanship, all have undergone tremendous changes. How can there be so many skilled carpenters now? ”

"Professor Nie seems to have a lot of feelings."

"Yes, the craftsman and the craftsman spirit are the rarest in this era. Look at Dad, when Dad's hand was not injured, the carpentry he did was not to mention that it was comparable to your grandfather, and even you could not be compared. ”

"What do you mean that even I can't compare? Did I make a poor model? ”

"Big head, you know that Dad doesn't mean that, if the model you make is poor, then Dad won't be able to make a model at all."

"Professor Nie doesn't need to be so modest, you obviously also made a model of Wan'an Bridge."

"It's made, but it took Dad a few years to make it, and it's not as beautiful as the Wan'an Bridge model you made in a summer vacation."

"Maybe I'm genetically better." Nie Guangyi paused: "In the final analysis, I still have to thank our Professor Nie." ”

"Dad took the students and your grandfather Qiu's apprentices to build a new bridge with a passing function and very similar to the original Wan'an Bridge, which will definitely be guaranteed, but if you want to say how exquisite and retro it is, there is not much possibility. Dad can't do God's restoration. ”

"Ahh Do we Professor Nie still know that God is restored? ”

"What's wrong? Do you look down on the elderly? ”

"How can we, Professor Nie should be so old and strong."

"What's strong? Daddy is old! ”

"It's old, so I said that you should be old and strong, and I didn't say that you are not old." Nie Guangyi is neither big nor small, a bit like he has returned to the state before he was eighteen years old.

"The big head has a lot of ability, and he will run on his father."

"Are you happy to be squeezed?"

"Happy."

Father and son looked at each other and smiled.

(End of chapter)