A novel building system has the potential to break down the industry boundaries between the real estate, construction, metallurgy, machinery and equipment manufacturing, and national strategic resources industries, combining them into a new industrial system. This is the steel structure building system, which is widely favored by industry insiders. This is the keynote speech on "Steel Structure and Green Building" given by Fang Hongqiang, President of Zhejiang Provincial Steel Structure Industry Association and Chief Engineer of Hanjia Design Group Co., Ltd., at the 11th National Academic Symposium on Modern Structural Engineering.

 

Steel Structure and Green Building

 

Fang Hongqiang, who is the chief engineer of Ji Group, president of Zhejiang Provincial Steel Structure Industry Association, expert of the Building Steel Structure Committee of China Architectural Metal Structure Association, and expert of China Steel Structure Association, has a deeper understanding of steel structure buildings than ordinary people. Fang Hongqiang believes that steel structure buildings are a major representative of green buildings.

 

Fang Hongqiang said that promoting steel structures in the field of construction engineering is an important part of the construction industry's development of a circular economy and represents a transformation and upgrading of the traditional civil construction industry. Steel structure buildings not only have four excellent properties of "light, fast, good, and economical," but also have the advantages of recyclability and minimal environmental damage. As is well known, steel structures have advantages such as high strength, light weight, good seismic performance, low foundation costs, large building usable area, high building quality, suitability for industrialization and standardized production, dry green construction, suitability for different climate conditions, no impact from construction seasons, and low overall cost. At the same time, steel structures can also reduce the pollution of construction waste to the environment and can be recycled throughout their lifecycle. Fang Hongqiang stated that steel structure buildings conform to China's development direction of energy saving, emission reduction, and circular economy and are one of the structures with the least impact on the urban environment.

 

According to Fang Hongqiang, steel structures have been widely adopted in developed countries and are therefore considered a major representative of green buildings. In Europe, green buildings are called ecological buildings or sustainable buildings. Green buildings in China refer to buildings that maximize resource conservation (energy saving, land saving, water saving, material saving), environmental protection, and pollution reduction throughout their lifecycle, providing people with healthy, suitable, and efficient usable spaces and coexisting harmoniously with nature. The development of green buildings has been explicitly included in the country's "Twelfth Five-Year Plan," marking the first time green buildings have been included in a national plan.

 

Fang Hongqiang believes that the most core value of buildings is to protect human life. The strong earthquake in Japan on March 11, 2011, again warned us: the massive destruction of houses and casualties were caused by the more destructive tsunami, not the collapse of houses. This is directly related to the high occupancy rate of steel structure buildings in Japan and Japan's emphasis on building disaster prevention, disaster resistance, and safe design that protects life. Fang Hongqiang emphasized that in the face of common human disasters, we have no reason not to learn from, not to be warned, and not to reflect.

 

Defects of Traditional Structural Buildings

 

When discussing the defects of reinforced concrete and masonry buildings, Fang Hongqiang said that because reinforced concrete and masonry buildings require manual operation and on-site wet construction, the noise and dust generated during construction have seriously endangered the health of workers. More importantly, the recyclability of reinforced concrete and masonry building materials is extremely low. The pollution of construction waste generated after reaching their lifecycle and the adverse impact on future generations have attracted widespread attention and concern from many domestic and foreign experts.

 

Chen Zhaoyuan, an academician of the Chinese Academy of Engineering and professor at Tsinghua University, said with deep concern: "The high-quality minerals used to burn cement are already in short supply, and the sand and gravel used to make concrete are already very tight in many places. In some areas, the mining of sand and gravel has already severely damaged riverbeds and vegetation. In coastal areas such as Ningbo and Zhoushan, the abuse of sea sand has brought major safety hazards to some projects." Scrap cars can be used to build steel structures.

 

Fang Hongqiang not only has rich theoretical knowledge but also rich engineering practice experience. As the chief designer of the Baotou Wangjun Daducheng residential project, the largest steel structure residential complex currently under construction in China, Fang Hongqiang is very optimistic about the industrialization of steel structure buildings.

 

Fang Hongqiang proposed that steel structure buildings should firmly establish the design concept of green buildings: following the concept of "zero resources, zero energy consumption, zero emissions, zero pollution, zero construction sites, and zero distance," a new model of building development and construction throughout the entire lifecycle from planning, design, construction, use, to demolition should be established. A new generation of modern steel structure residential building products that meet the requirements of industrialization, standardization, and industrialization should be developed, designed, and constructed.

 

Fang Hongqiang used a common multi-story frame structure building of 3 to 4 stories to compare steel structure buildings and wooden structure buildings. If wooden structures are used, generally 40 to 50 trees with an age of about 10 years are needed; while using steel structure buildings, only the steel from 6 scrapped cars is needed. Fang Hongqiang said that with the popularization of automobiles, the "problem of scrapped automobiles" will also emerge after "difficulty in traveling and difficulty in parking." Using steel structures to "digest" scrapped automobiles will be a good choice. Comparison of steel structure buildings at home and abroad

 

Fang Hongqiang said that in 2009, China's construction consumption of steel accounted for about 50% to 60% of the total steel output, which is comparable to the average steel consumption level in the world. However, China's construction mainly uses steel for reinforcement, steel wire, and steel strand in reinforced concrete. The steel used for real steel structure buildings only accounts for about 10%. In China's housing construction, the building area of steel structure buildings accounts for about 2%, while in developed countries, it accounts for 40% to 60%. In Japan, steel structure buildings account for about 50% of the total number of buildings; in South Korea, steel structure buildings account for about 20% of the total number of buildings. It can be seen that China's steel consumption for steel structure buildings is seriously low, which forms a huge contrast with the rapid growth of China's steel output. This is also a major reason for the overall oversupply of steel in China.

 

The Current Situation and Trend of Steel Structures in China

 

Fang Hongqiang believes that Chinese people are not good at using steel because China used to be a country with a serious shortage of steel. The latest data show that in 2010, China's steel output was more than the sum of Japan, the United States, and other countries ranked 2nd to 10th, accounting for 43.3% of the world's steel output. The continuous growth of China's steel output has laid a solid foundation for the development of steel structure buildings in China.

 

Fang Hongqiang believes that China currently has the basic conditions for developing steel structure buildings. First, the "standards," "specifications," and "regulations" have been basically improved; second, the design tools (software) are complete; third, it has the ability for technical research and product development; fourth, a complete personnel education and training mechanism has been formed domestically.

 

Fang Hongqiang said that currently, there are more than 1,000 steel structure manufacturing enterprises in China, and their manufacturing and construction and installation capabilities have been improved overall. Taking Zhejiang Province as an example, there are dozens of well-known steel structure manufacturing and construction enterprises such as Jingong, Southeast, Hangxiao, and Hengda, and their equipment level, production technology, and management capabilities are close to international levels.

 

Fang Hongqiang said that focusing on technological innovation, reforming the traditional building system, promoting the industrialization, standardization, and supporting of the steel structure industry, promoting the development and application of steel structures in engineering construction, using steel instead of wood to protect the earth's ecological resources; using steel structures instead of concrete structures to promote green and environmentally friendly buildings has become a new method and new idea for sustainable development in the field of engineering construction.

 

Fang Hongqiang believes that currently, combining steel structure buildings with China's affordable housing project can not only solve the housing problem for the people during the 12th Five-Year Plan period, but also solve the problem of labor surplus caused by overcapacity in steel production. Fang Hongqiang said that in the long run, due to the relative lack of high-quality iron ore resources in China, steel, as the food of modern industry, will inevitably become a bottleneck restricting China's rapid advance towards modernization, while a large number of steel structure buildings are very valuable high-quality resources. Fang Hongqiang stated that the combination of steel structure buildings with China's urbanization construction and affordable housing projects is actually a long-term strategic reserve industry for the country, which can benefit future generations, and its significance is even greater.