In order to welcome Professor Lin, the most famous concrete expert in China, the Huhai Construction Engineering Administration set up a few tables in the hotel, and Li Ruoyu of course also participated, not only Mi Yun also participated.

Li Ruoyu originally wanted to sit at a table with Xie Zili, but he didn't expect Professor Lin to ask Mi Yun to pull him to Professor Lin's table, you must know that this table is all the leaders of the Shanghai Construction Engineering Administration and Professor Lin, Li Ruoyu didn't understand why Professor Lin asked him to sit together.

After three rounds of drinking, Professor Lin smiled and said, "Mr. Li, Comrade Qin Haijuan of your company spoke very well today!" Your research is very well done, and there are a lot of new ideas that you have come up with! If you have the chance, we can work together! ”

Li Ruoyu said excitedly: "Professor Lin is too polite! Of course, our company is willing to cooperate with the most famous universities in China to engage in concrete research, especially the research of high-performance concrete, which cannot be completed by our private enterprises. At present, we have cooperated with Gongji University, Fuming University, and Huhai Concrete Technology R&D Center, and it would be even better if we could cooperate with Shuimu University! ”

Professor Lin laughed and said, "Mr. Li is too polite! An entrepreneur like Mr. Li, who is both young and knowledgeable, can be said to be difficult to find a second one in China! I am optimistic about the development prospects of your company! At present, China is still far behind developed countries in the research of high-performance concrete. In fact, the premature failure of concrete structures in many works such as bridges, roads, seaports and sewage buildings is not due to insufficient strength, but due to insufficient durability. Due to the high cost of repairing damaged concrete buildings, such as in the United States, for example, the annual repair cost of deteriorated concrete is as high as 100 billion dollars, which makes many designers realize the importance of concrete durability. We began to consider whether it was possible to use high-performance concrete structures with a long service life, for example, not 30~50 years but 100 years. In response to the premature deterioration of concrete, in the mid-80s, a research project on the development of high-performance concrete with the main goal of improving the durability of concrete materials was launched, and it was valued by various governments. Durability design methods for concrete structures are now the focus of research in the field of civil engineering. In view of the erosion of different environmental categories, the theoretical or empirical model of material performance deterioration is proposed, and the service life of the structure is estimated accordingly, which has become the mainstream of development and research durability design methods. In this regard, we at Mizuki University do have some technical reserves. ”

Li Ruoyu nodded and said: "Yes, Shuimu University is the top in the field of civil engineering in China, and there are authoritative experts like you, Professor Lin. As long as there is a strong appeal from experts like you, I believe that the application of high-performance concrete will increase. In the past 100 years, the development trend of concrete has been to increase its strength. The average was 10MPa in the 30s, about 20MPa in the 50s, about 30MPa in the 60s, and has risen to 40MPa in the 70s. ”

"As the largest amount of man-made material, concrete cannot but consider the impact of its use on the ecological environment. The raw materials of conventional concrete are derived from natural resources. For every 1t of cement, it is about 0.6t of clean water, 2t of sand, and more than 3t of gravel; For every 1t of Portland cement, about 1.5t of limestone and a large amount of coal and electricity are burned, and 1t of carbon dioxide is emitted, and the increase in the concentration of carbon dioxide in the atmosphere is one of the causes of global warming. Although the energy consumed and the pollution caused by the production of concrete is relatively small or much smaller than that of other building materials such as steel, aluminum, plastic, etc., and concrete itself is a clean material, due to its large amount, excessive mining of ores and sand and stone aggregates can cause resource destruction and severely affect the environment and natural landscape. On the other hand, due to the premature deterioration of concrete, how to dispose of the concrete waste after the demolition of the old project also poses a threat to the environment. Green concrete can completely solve the problem of urban garbage and sludge, and is the most effective way to protect the ecological environment and achieve zero pollution. ”

Professor Lin nodded, "Not bad." Therefore, the amount of cement used in the future concrete must be fundamentally reduced, and various industrial waste residues must be used more as its raw materials; The recycling of waste concrete must be fully considered, and the concrete of the future must be high-performance and, above all, durable. Durability and strength both mean conserving resources. After the development and application of high-efficiency superplasticizer in the 60s of the 20th century, concrete technology entered a new field of high strength and high fluidity. In recent years, China has begun to apply C60 high-performance concrete in railway, highway, bridge construction, high-rise buildings and airport construction projects. In the world, high-performance concrete with a strength of 90MPa, 100MPa, 110MPa, 120MPa, and even greater than 150MPa and 200MPa has begun to be applied in engineering. We must also seize the opportunity and rise to the challenge. ”

Li Ruoyu agreed: "Yes, I think the development of high-performance concrete has the following directions, one is green high-performance concrete. Cement concrete is the largest man-made material in modern times, which consumes resources and energy and destroys the environment very much, which is contrary to the requirements of sustainable development. Compared with the benchmark concrete, fly ash concrete greatly improves the working performance of fresh concrete, significantly reduces the heat of hydration in the hardening stage of concrete, and improves the strength of concrete, especially in the later stage. Moreover, it saves cement and reduces environmental pollution, and becomes a representative material of green high-performance concrete. The second is ultra-high-performance concrete, such as active powder concrete, which is characterized by high strength, compressive strength up to 300MPa, and high compactness, which can be applied in special projects such as military and nuclear power plants. The third is intelligent concrete, which is a multi-functional material that combines intelligent components on the basis of the original components of concrete, so that the concrete material has self-perception, self-adaptation and self-healing characteristics, and has the function of sensing and controlling environmental changes. For example, a series of sensitive concrete, such as damage self-diagnosis concrete, temperature self-regulating concrete, and bionic self-healing concrete, can lay a foundation for the research, development and application of intelligent concrete structures. ”

Professor Lin looked at Li Ruoyu with appreciative eyes and said: "Yes, there is still a considerable gap between China's concrete industry and developed countries in terms of pollution prevention and energy consumption control, and there are still many arduous tasks to be completed. We must attach great importance to the significance of protecting the ecological environment, adhere to the scientific development strategy, and make every effort to develop green high-performance concrete. The process of development must be protected by the government's control and management and laws and regulations, the self-discipline and active participation of enterprises, and the investment and innovation of science and technology. With these, we can be confident that the future of concrete is green. (To be continued.) )