1. Comprehensive comparison and analysis with traditional wood formwork

Aluminum formwork has high strength, good rigidity and high reuse times; The construction technology is simple and easy to install; No construction waste is generated, and the recycling value after scrapping can reach 30%. The strength and stiffness of bamboo (wood) formwork are not as good as aluminum formwork, and the turnover times are very low; Moreover, the construction site is messy and has no recycling value, resulting in a large amount of construction waste. Aluminum formwork is resistant to acid, alkali, humidity, cold and heat, and does not deform. It is suitable for safe operation under various construction temperature environments.

2. Comparison of technical and economic indexes with traditional wood formwork, combined steel formwork and all steel large formwork

Compared with combined steel formwork and expanded combined steel formwork, building aluminum formwork has light weight, large single area, simple manual operation, strong adaptability to construction environment, no rust in rainy and humid areas, alumina protection, long service life, high turnover times, and normal reuse of formwork can reach more than 300 times. The cost of transportation, tower crane, maintenance and scraping is low, and the benefit is obvious. The recycling value is high. It can be fully recovered after scrapping, and the residual value can reach 30%. Compared with the all steel large formwork, the all steel large formwork is heavy, completely depends on the mechanical installation of tower crane, and has high construction cost. It is suitable for the walls and columns of large buildings, and is only suitable for the construction method of twice formwork erection → pouring → formwork removal of walls, columns and beams. During integral pouring, it can only be used for external wall formwork. The building aluminum formwork is light in weight and can be manually handled, assembled and disassembled without the assistance of mechanical equipment. It can be used for both overall pouring and secondary pouring, with a wide range of application.

In terms of applicable environment, due to its material, steel formwork is afraid of acid, water, moisture and corrosion, so it can not be constructed in some special environments; The building aluminum formwork is acid and corrosion resistant and can adapt to more construction environment.

Because the thermal expansion coefficient of steel and concrete is similar, the formwork and newly poured concrete are easy to be firmly bonded and not easy to demould; The surface of aluminum formwork has oxidation protection, which is not easy to paste with concrete and easy to demould.

3. Cost analysis of building aluminum formwork used in high-rise and super high-rise concrete structure engineering

The use of building aluminum formwork saves a lot of materials and labor costs. When the structural surface reaches the clean water effect and enters the decoration stage, the plastering and leveling process of the inner wall can be omitted, and the common problems of hollowing and cracks in the plastering of the indoor wall can be eliminated in terms of quality; From the perspective of construction cost, the raw material consumption of cement and sand and plastering labor are saved, and the use time of turnover materials is reduced; From the analysis of construction period, the man hours in the interior decoration stage can be shortened, and the project progress can be shortened by 1 ~ 2D according to each floor, which is beneficial to the total construction period.

For more than 30 floors, the input cost of formwork and support does not decrease with the increase of floors. With the increase of floors, the wood consumption increases in direct proportion; Steel formwork and aluminum formwork have almost no material consumption, and the investment is significantly reduced. In particular, aluminum formwork is easy to implement early removal technology, and the overall cost reduction is more obvious.

Comparison of construction period: wood formwork needs the most days, followed by steel formwork, aluminum formwork is easy to be removed early, and the number of days is the least. For multiple building groups, such as community projects, the difference of formwork and support input cost and economic benefit is more obvious. Therefore, industrial developed countries are increasingly using building aluminum formwork technology.

For other comprehensive benefits, from the analysis of household use area, the net length and width of the room can increase the use area by 3 ~ 125px. From the aspect of design safety, the plastering of the clean water wall is omitted, the self weight of the building is reduced, the seismic force is correspondingly weakened, the injury caused by plastering falling is reduced, and the seismic resistance of the structure is partial to safety. From the analysis of social reputation, using the formwork system, the construction site environment is clean and tidy, which greatly improves the overall image of the enterprise.

4. China promulgated and implemented the guidelines for green construction on September 10, 2007

(JZ [2007] No. 223) (hereinafter referred to as the guidelines), which has experienced for 4 years. The guidelines are used to guide the green construction of construction projects. Its contents are composed of six parts: General principles, green construction principles, overall framework of green construction, key points of green construction, new technology, new equipment, new materials, new technology and green construction application demonstration project. Among them, the key points of green construction include green construction management, environmental protection, material saving, water saving, energy saving and land saving. In the key points of green construction, material saving and material resource utilization are very important and characteristic in the guidelines. From material saving measures to material turnover, such as quantitative index requirements for material loss rate; Take technical and management measures to improve the turnover times, construction speed and professional construction of formwork and scaffold.

Building aluminum formwork technology is processed from aluminum profiles formed by integral extrusion. The whole system has high standardization, light weight, strong bearing capacity and high matching accuracy. No construction waste will be generated during construction, and zero discharge of construction waste can be achieved. It has many times of material turnover, high residual value and renewable utilization, which meets the requirements of green building. Do not waste resources and avoid disposal of waste templates. Replacing wood with aluminum can save wood resources and protect the environment, which is in line with green environmental protection. In addition, tower cranes and other mechanical equipment are not required to assist in the construction process. The construction technology of building aluminum formwork includes the scientific management and technical progress of the construction project, the maximum conservation of forest wood resources and the reduction of negative impact on the environment, and the main contents of four sections and one environmental protection, including advanced formwork material technology, support technology for quick removal and early removal of formwork, reducing construction personnel, reducing labor intensity, accelerating construction progress Improve construction quality, implement civilized construction management, These are the main contents of the 10 new technologies in construction industry (2010). In foreign technologically advanced developed countries, building formwork technology began to be applied as early as the 1960s because of its remarkable characteristics of high intensity, high turnover times and green environmental protection. Under the guidance of the guidelines, it also began to be more and more widely used in concrete structure construction projects in China.

After more than 50 years of development, China's aluminum extrusion industry has become a major country in the production, consumption and export of aluminum extrusion materials, demonstrating China's "green aluminum industry" to the world,

It has contributed to the development of China and the global economy. China's aluminum extrusion industry has the preliminary characteristics of the global aluminum extrusion export base in terms of technical equipment and production scale, which has laid a good foundation for the development of aluminum formwork technology in China.