亚洲五月综合缴情综合久久_jlzz大jlzz大全免费_十八禁av无码免费网站_99国产美女露脸口爆吞精

"The main resistance to the promotion of wood structure building is the concept problem. In addition, the industrial capacity, design and construction capacity of China's wood structure building cannot be achieved, so it is not realistic to promote wood structure building nationwide at present." Han aixing, deputy director of the Department of building energy conservation and science and technology of the Ministry of housing and urban rural development, said of the prospect of wood structure promotion.
Recently, in the "China modern wood structure building promotion action" and "dream home" cup Dandong port wood structure competition, experts, scholars, business representatives and relevant government leaders exchanged and discussed the current situation and development of China's modern wood structure building.
Jiang Zhongqiao, deputy director of the center for science, technology and industrialization development of the Ministry of housing and urban rural development, pointed out that wood structure building has a long history of development in China. At present, the development of wood structure building in western countries is relatively mature. It has unique advantages that reinforced concrete does not have: wood itself is a good insulator, and its heat preservation and insulation performance is good. Its heat insulation performance is 15 times that of concrete, and it is steel. The material is 400 times of that of "warm in winter and cool in summer".
Experts and scholars at the meeting also mentioned the seismic performance of wood structure for many times, which is incomparable to brick concrete structure building materials. Because of its light weight, good flexibility, absorption and consumption of external forces, the light wood structure building has strong stability in the earthquake, and its destructive force is far less than the concrete building. In addition, the wood structure building also has the advantages of low carbon pollution-free, sound insulation effect, low thermal conductivity.
On the issue of fire prevention, according to Mao Linhai, Secretary General of China modern wood structure construction technology industry alliance, there are two main promotion systems: light wood structure and heavy wood structure. The fire prevention of light wood structure depends on gypsum board. When decorating, a layer of gypsum board should be installed in the building, which can effectively insulate the heat and play a role in fire prevention. The fire protection function of heavy-duty wood structure is mainly realized by the large-scale section of wood. When the large-scale section of wood encounters fire, its strength retention time is longer than that of metal.
With regard to the waterproof and moisture-proof problems, for modern wood structure buildings, designers should pay great attention to the problem that wood will be mildewed and rotted if soaked in water for a long time in the design, so designers will add breathing paper on the building wall. This breathing paper is one-way breathing paper, the water vapor inside can be released, but the water vapor outside cannot enter. In addition, there is a cavity between the walls for air circulation and keeping the wood dry without deformation.
In view of the current situation and future development of wood structure buildings, Mao Linhai said: "ten years ago, the first tier cities, such as Beijing, Shanghai, Nanjing, Hangzhou and other first tier cities, developed well as the surrounding areas. In recent two years, especially with the advancement of new urbanization, the demand for wood structure buildings has been formed from north to south. But at present, the wood structure construction mainly focuses on the middle and high-end construction projects. "
According to Han aixing, at present, the technology of wood structure is very mature, and its application prospect should be very good. If we can't meet the requirements of promotion, it may be because our current industrial capacity, design and construction capacity still can't meet the requirements. For this reason, Han aixing suggested that comprehensive promotion should be gradually realized from planning policies, scientific research and development, demonstration projects, training of technicians, etc.