Abstract: 'Steel structure buildings are representative projects for implementing building energy conservation, possessing significant green building characteristics.' During the 12th Five-Year Plan period, Zhejiang Province will newly build more than 3 national residential industrialization bases, over 10 national healthy and comfortable housing demonstration projects, and more than 20 residential communities that pass national residential performance certification. Zhejiang Province's determination to develop green buildings will greatly promote the development of the steel structure industry.
Steel structure buildings are representative projects for implementing building energy conservation, with significant green building characteristics,' said Yao Bing, President of the China Construction Metal Structure Association and former Chief Engineer of the Ministry of Construction. In the field of steel structures, many experts share Yao Bing's view. Building energy conservation has become a consensus. Data shows that currently, building energy consumption in China accounts for about 30% of the total social energy consumption, and buildings account for nearly 50% of the total carbon dioxide emissions. Therefore, building energy conservation is urgent.
China is currently one of the countries with the most new constructions annually, with about 2 billion square meters of new buildings each year consuming approximately 40% of the world's cement and steel. It is reported that the average lifespan of buildings in European and American countries (regions) is over 80 years, while that of buildings in China is only 50 years. Amidst the booming construction boom, 'short-lived buildings' emerge endlessly, and many 'young' buildings are forced to 'die prematurely'. While boasting about GDP, people have not realized the disaster left to society and future generations by the increasing amount of construction waste.
Fortunately, developing green buildings has been explicitly written into the national '12th Five-Year Plan'. The 2012 Government Work Report pointed out that promoting industrial structure optimization and upgrading requires vigorously developing high-end equipment manufacturing, energy conservation and environmental protection, new materials, and other industries. Expanding the scale of technical transformation special funds to promote the upgrading and transformation of traditional industries. The Government Work Report mentioned that the key to energy conservation and emission reduction is saving energy, improving energy efficiency, and reducing pollution. It is necessary to formulate and issue a work plan for the reasonable control of total energy consumption as soon as possible, accelerate the rationalization of the energy price system. Comprehensively using economic, legal, and necessary administrative means, focus on energy conservation and emission reduction in key areas such as industry, transportation, construction, public institutions, and residents' lives, and thousands of key energy-consuming enterprises, further eliminate backward production capacity.
In July 2011, the Ministry of Housing and Urban-Rural Development issued the '12th Five-Year Plan for the Development of the Construction Industry', which requires that the unit added value energy consumption during the construction process of building products decrease by 10%, and the proportion of steel structure projects increase. 100% of newly built projects should meet the national building energy conservation standards in engineering design, and newly built projects should meet the national building energy conservation standards requirements in construction. The plan requires improving the industrialized manufacturing level of building components and parts, promoting integrated and modular production of structural components; encouraging and promoting menu-style fully decorated delivery for newly built affordable housing and commercial housing. The introduction of relevant policies fully demonstrates the country and the Ministry of Housing and Urban-Rural Development's resolve in building energy conservation.
Steel Structures and Green Buildings
Europe refers to green buildings as ecological or sustainable buildings. The United States calls them green buildings. China defines green buildings as 'buildings that, throughout their entire life cycle, maximize resource conservation (energy, land, water, materials), protect the environment and reduce pollution, provide people with healthy, applicable, and efficient usage space, and coexist harmoniously with nature.
Professor Shen Zuyan, Academician of the Chinese Academy of Engineering and professor at Tongji University, said, 'China's construction industry has been a major consumer of energy, materials, water, and other resources in recent years. Promoting the application and popularization of steel structures fully conforms to the country's initiative to build a resource-saving society and meets the current national requirements for sustainable development of the construction industry.' Shen Zuyan summarized four characteristics of steel structure buildings as 'light, fast, good, and economical'. Light - Steel structure buildings have light weight and high strength. The weight of steel structure residences is about 50% of that of reinforced concrete residences, and the usable area is increased by about 4% compared to reinforced concrete residences. Fast - Steel structure buildings have a high degree of industrialization and short construction periods. Under the same conditions, the construction period of steel structures is only 1/3 to 1/2 of that of reinforced concrete structures. Good - Steel structure materials have good properties and high reliability. In past earthquakes at home and abroad, steel structures have suffered minimal damage and are widely recognized as suitable structures for seismic fortification areas, especially strong earthquake zones. Economical - From the perspective of current material prices alone, steel structures are more expensive than concrete structures, but steel structures are about 50% faster to construct than concrete structures, saving a lot of time costs. Moreover, the overall weight of steel structure buildings is more than 50% lighter than concrete structures, thus reducing costs for foundation treatment and transportation. Building houses is a systematic project involving many links such as design, manufacturing, transportation, installation, maintenance, and management. Therefore, from an overall perspective, steel structures are more 'economical'. In addition, steel has the characteristic of being recyclable and reusable, which is conducive to energy saving, material saving, water saving, and land saving compared to other building materials commonly used today. Shen Zuyan's concise summary of steel structure buildings perfectly aligns with the characteristics of green buildings.
Fang Hongqiang, President of the Zhejiang Steel Structure Industry Association and Chief Engineer of Hangjia Design Group Co., Ltd., combined the characteristics of steel structures and proposed the 'six zeros' architectural design concept centered on green buildings - 'zero resources, zero energy consumption, zero emissions, zero pollution, zero construction site, and zero distance'. He applied this concept to the currently under-construction Wanjun Dacheng residential project, a steel structure residential community in China. As the chief designer of the Wanjun Dacheng residential project, Fang Hongqiang is very optimistic about steel structure buildings taking an industrialization path. During the design and construction of the Wanjun Dacheng residential project, Fang Hongqiang fully utilized the three major advantages of steel structure building systems: moderate adjustability of unit structure, replaceability of non-load-bearing components, and recyclability of steel. Following the design philosophy of green buildings and taking 'six zeros' as the design standard, he established a new model for the entire life cycle of buildings, from planning, design, construction, use to demolition. He designed and constructed a new generation of modern steel structure residential building products that meet industrialization, standardization, and industrialization production. The model of Wanjun Dacheng plays a very important示范 and guiding role in accelerating the process of residential industrialization, changing traditional residential production methods, and promoting energy conservation, reduction of consumption, and environmentally friendly and low-carbon buildings.
Policies Safeguard Green Buildings
According to Fang Hongqiang, on August 1, 2011, the Zhejiang Provincial People's Government first issued the 'Several Opinions on Actively Promoting the Development of Green Buildings'. The overall goal of the opinions is to strive to significantly enhance the whole society's awareness of green energy conservation by 2015, take the lead nationwide in basically forming a green building development system, and achieve a leapfrog development from energy-saving buildings to green buildings. The scope and proportion of recycling of building materials will be further expanded, and the total consumption of non-renewable resources by newly built buildings will decrease by 10% compared to the current level. The level of residential industrialization will be further improved, and the floor area of residential industrialization projects will account for more than 35% of the total floor area of newly completed residential buildings in the same year.
During the 12th Five-Year Plan period, Zhejiang Province will newly build more than 3 national residential industrialization bases, over 10 national healthy and comfortable housing demonstration projects, and more than 20 residential communities that pass residential performance certification. In terms of residential industrialization, Zhejiang Province will focus on affordable housing projects to accelerate the promotion and popularization of residential industrialization models and improve the scientization and intensive development level of the residential industry.
To ensure the smooth implementation of the goals, Zhejiang Province has put forward six safeguard measures: strengthening organizational leadership, increasing financial input, implementing supportive policies, strengthening legal system construction, reinforcing technical support, and strengthening publicity and guidance. It requires governments at all levels to further increase investment in green building development, gradually increase building energy conservation special funds, and focus on supporting projects such as green upgrading of newly built buildings, energy-saving renovation of existing buildings, construction science and technology innovation, and application of renewable energy in buildings. Energy-saving building projects and green buildings that obtain low-energy consumption building energy-saving marks through building energy efficiency assessment, as well as national healthy and comfortable housing demonstration projects and buildings with national residential performance certification marks, will enjoy enterprise income tax preferences if they meet the relevant provisions of the Enterprise Income Tax Law. National and provincial residential industrialization demonstration projects and star-rated green building projects will be given support in the form of floor area rewards and tax and fee reductions. Vigorously promote the application of advanced new green building technologies, processes, materials, and equipment at home and abroad, and focus on improving the technical content of green buildings. Zhe