At present, the curtain wall dry hanging stone design, the design unit usually only provides the vertical surface division form and a small number of node diagrams, the degree of detail can not reach the degree of construction according to the figure, therefore, the deepening design work of the stone board and related dry hanging system is very necessary This work is generally carried out by the hanging board construction unit. Due to the uneven level of technology, many stone projects do not even have corresponding mechanical calculations and field test verification. The selection and determination of stone and dry hanging systems are based on daily construction experience, which may cause dangers of insufficient strength or Excessive material is wasted.
The design of dry hanging stone must be carried out in accordance with the relevant regulations and in strict procedures. The mechanical calculation conclusions should be consistent with the mechanical performance test results on site. According to the engineering practice of stone curtain wall construction and design, this paper introduces the dry hang from various stages such as stone, keel, pendant material selection, physical experiment performance, mechanical calculation, simulation of actual field performance test and construction drawing design. The whole process of stone design.
General:
The deepening design of the stone curtain wall usually determines the precise grid size, color, material, caulking material, etc. according to the drawings provided by the designer, and draws a detailed outline of the stone and detailed details of the nodes of each complex part, and then The weight, size and seismic and wind pressure requirements of each single stone are subject to relevant mechanical calculations to determine the dry hanging method of the stone and the dimensions of the keel system, embedded parts and connectors. And in the case of conditions, the calculation results are subjected to on-site mechanical performance tests to ensure the safety of the stone curtain wall.
1. Choice of stone
For the deepening design, it should cooperate with the work of the design unit and the construction party. According to the design requirements of the design of the curtain wall and the color of the building, the construction party will be provided with various stone samples to help them determine the stone used as soon as possible. Generally, in the selection of several kinds of stone materials, the technical characteristics of the surface features, colors and textures of the stone to be used should be considered according to the stone materials. Although the stone supplier has given the physical properties of the stone, the physical properties of the stone as a natural material vary greatly, so it must be reconfirmed in order to establish the corresponding design indicators for the stone design.
2. The choice of dry hanging method
There are several types of dry hanging of stone, such as steel pin type, through groove type, short groove type and back bolt type. The common ones are short groove type and back bolt type. The suspension method is relatively short groove type. The cost is lower but the safety is not as good as the back bolt type. It is usually used when the weight of the stone is not too big or the safety factor is not too high. The back bolt type is stable and stable, but the cost is high. It is used for larger stone (thickness 30) When the stone area is larger than 1.5m2 when mm) or when the stone safety performance is high.
3. Mechanical calculation of stone and dry hanging system
Firstly, determine the load and action form of the curtain wall, then determine the dry hanging method of the stone, and then determine the calculation model of the stone plate, calculate the force safety, and finally determine the structural form of the dry hanging system according to the load value of the dry hanging system. And the dimensions of the pendants, connectors, embedded parts and horizontal and vertical keels used. The design of the stone and its dry hanging system shall comply with the requirements of the national industry standard "Technical Specifications for Metal and Stone Curtain Wall Engineering" JGJ133-2001.
3.1 Determination of load
The material's own weight, the wind load and the seismic load are usually taken into account in the calculation and combined according to the way the load acts. The corresponding sub-coefficient and combination coefficient should be taken strictly according to the requirements of the specification. For some special buildings, there are special requirements for calculating the corresponding load in the design specification, and the maximum value should be compared with the specification in the calculation. . When calculating the dry hanging system, the mechanical calculation of the load is determined according to the characteristics of the force transmission of the rigid body. sometimes. When some loads are not easy to determine, they can be determined by simulation tests.
3.2 Calculation of stone
The calculation of the stone mainly includes the calculation of the bending resistance of the hanging plate itself and the shear calculation of the connection between the hanging plate and the hanging pin. Sometimes the thermal cracking stress of the stone should also be calculated. The calculation method is related to the dry hanging method of the stone. This article uses the back-bolt dry hanging stone fixing system to illustrate. The loads on the stone slab include horizontal wind loads and seismic loads, vertical seismic loads and stone weight. And thermal cracking stress caused by temperature changes. The typical installation system of the back-bolt type dry-hanging stone is to fix the stone by two sets of four (four groups) hanging pieces, wherein the two sets of hanging pieces on the stone support the weight of the stone and restrain the stone in the direction perpendicular to the stone plane. The lower two sets of pendants only act to constrain the stone in a direction perpendicular to the plane of the stone. When calculating the bending resistance of stone, the stress should be calculated according to the four-point support plate. The calculation value of the maximum bending stress obtained by calculating the side lengths a0 and b0 should not exceed the design value of the bending strength of the stone board; when the shear stress generated by the back bolt part on the stone board is subjected to shear calculation, it is generally based on the corresponding empirical formula. The calculation requires that the standard value of the shear stress of the slab is not greater than the design value of the shear strength of the sheet. It should be noted that the vertical shear stress is only borne by the two sets of pendants in the upper row, rather than by all four sets of pendants.
8pcs T handle hex key set,hex key set,hex key manufacturer,T handle hex key
henan horn tools co.,ltd. , https://www.hornhandtools.com