2  Status of use of building formwork in China
At present, there are mainly three types of formwork in construction market, they are steel formwork, wood (bamboo) plywood formwork and plastic formwork.
2.1  Combined steel formwork
The steel formwork is represented by a shaped tool-type formwork that can be assembled into various sizes and shapes using connecting members, which can be applied to different structural forms, in addition to saving wood, and also a major reform in the construction process of concrete. The use of steel formwork can improve the progress of the project, improve the construction quality, save engineering costs and improve labor efficiency. It is not only a formwork that can be used in civil building structures and general industrial building structures, but also a sliding formwork that can be used in high buildings and tunnel construction.

2.2  All steel large template
In the construction process of the cast-in-place shearing wall, the all-steel large formwork is generally used. This formwork can freely combine the modularized plates, which can fully satisfy the construction requirements of different buildings and can be largely Improve the quality and efficiency of the construction of the shearing wall structure, simplify the construction process, save construction costs, and shorten the construction period. All steel large forms can be reused more than 500 times.
2.3  Wood plywood formwork
Wood plywood formwork has many advantages, such as repeated use, strong wear resistance, smooth and smooth surface, good performance, lighter materials, etc. In the construction process of the structure, it is more suitable to use this template, and this template form has been widely used in foreign countries. As early as in the construction of the 1970s, China has used wood plywood formwork, and in recent years, some construction projects in the country have also used wood plywood formwork, but the Lack of timber resources makes it difficult to promote and apply this form of template.

2.4  Bamboo Plywood Formwork
The bamboo plywood formwork has the following advantages such as low price, good performance and abundant resources. It is a more rational material that can be used as a building formwork. It is mainly applied to platforms and floors. At present, more than 80 manufacturers have been able to produce this bamboo plywood formwork, with an annual production capacity of about 7.5 million square meters. According to relevant surveys, the actual annual output of bamboo plywood formwork reached 2.15 million square meters in 1994, and it has increased to 4.6 million square meters in 1997. This output has already occupied 50% of the annual output of steel formwork in China. Whether in the national new technology demonstration project or in the key projects in various places, bamboo plywood formwork has been widely used and has a good use effect.

To be continue…