The following is to bring you about what is the building template engineering related content, for reference.
First, the basic characteristics of construction of building engineering template engineering.
1, the requirements of formwork engineering in the construction of concrete structure, in order to ensure the construction safety and engineering quality of concrete structure
To improve the progress of the project and reduce the cost, there are four basic requirements for the construction template: first, to ensure the accurate position and size of concrete components and each part of the structure. It mainly includes plane elevation, position, section size and shape to meet the standards of design drawings; Second, it has sufficient stiffness, stability and strength. The formwork plywood can withstand the side pressure, mass and load generated by construction of newly poured concrete. It can be said that the formwork ply can bear various loads in normal use and construction time. In the process of concrete pouring, vibration and maintenance, there will not be the following extreme state: the whole component and structure lose part of balance; Due to insufficient material strength, structural connections and components were damaged. Or because of too much plastic deformation, can not continue to bear the load; Structural transformation to mobile system, components, structures lose stability; Third, the structure should be simple and convenient to assemble and disassemble. Meet the technical requirements of reinforcing bar installation, binding, concrete pouring, maintenance and so on. Structural stress is clear, suitable for centralized manufacturing, in order to improve the template manufacturing factory, mechanization, so that the raw material to a certain degree of savings. Flexible assembly and disassembly, simple, conducive to improve work efficiency, reduce labor intensity, improve construction progress; Fourth, the template needs tight seams. If juncture does not reach a requirement, must adopt reliable method to undertake processing in time, wait like thin iron sheet, plastic cloth, nail linoleum, in order to ensure not to produce leakage oar.
2, China’s construction template system
There are three main formwork shuttering plywood systems in China: permanent, instrumental and combined.
In the early 1970s, the realization of steel instead of wood, gradually separated from and finalize the wood template and scattered scattered support
Template. To the 1980s, the rise of high-rise buildings in China, the building structure from brick structure to pouring concrete structure transformation, this structure cost is lower, seismic, overall, fire performance is better, thus promoting the rapid development of China’s formwork technology. With the efforts of Chinese researchers, three systems of permanent, instrumental and combined have been developed gradually.
3, cast-in-place template selection early demolition technology cast-in-place floor slab in the construction process, for load-bearing templates, how to speed up the turnover, directly affects the input of the template and the cost of the project. Conventional mold support method, high-rise, multi-layer construction construction, turnover need to set 3~4 layers of template and support, a large amount of investment. The early disassembly technology can reduce the strength of the disassembly by 20% for the horizontal structure with span less than 2m, and the disassembly can reach 50% of the design strength. Therefore, only the appropriate support template, add support point, the larger span of the floor into the floor span of less than 2m, reduce its demolition strength to 50%, resulting in template early demolition, pillar demolition. Thus speed up the template turnover, reduce 1/3 to 1/2 of the template configuration. Concrate early removal technology mainly depends on the early removal of stigma, now the early removal of stigma mainly spiral, support locking plate, assembly, inclined surface self-locking structure of early removal of stigma.
4, China has a very rich bamboo resources, producing area of about 1/4 of the world’s bamboo forest area, choose bamboo as panel raw material, made of bamboo plywood, can have a larger carrying capacity, but also reduce water absorption rate, expansion rate and shrinkage rate. Bamboo plywood has many turnover times, low price, can cut sawing, smooth surface, good construction performance and so on. Therefore in more than ten years of development, in the construction of concrete structures in rapid popularity, so in the water requirements of the concrete floor and wall formwork shuttering.
5, high-rise, high-rise buildings, such as the use of climbing template climbing template is a vertical structure as the support point, through the climbing equipment to climb from bottom to bottom. Therefore, climbing formwork is mainly used for vertical concrete structure construction formwork technology. It combines sliding template and large template technology, its advantages are as follows: first, the height of the large template and the whole building parallel, the rhythm and sequence of operations with large template construction is relatively close, can ensure the quality and size of concrete components, structure; Second, layer by layer configuration of the template, a sexual assembly, vertical construction from bottom to top, until the concrete structure is completely completed, then the demolition, do not need to frequent each layer of template support demolition; Third, lifting templates usually use their own equipment, lifting does not need to use other lifting equipment.
