1.2 post embedded parts post embedded parts are flat embedded parts, which are fixed by ordinary expansion bolts, chemical anchor bolts or through bolts (double studs) and welded closed steel plates
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The flat plate embedded parts occupy a large volume, and the anchor bars are generally arranged in two rows and two columns, which is very easy to interfere with the main reinforcement of the main structure
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This kind of embedded parts adds reserved slots on the basis of ordinary claw embedded parts, which is very convenient to connect
The interference between anchor bars and the interference between anchor bars and structural reinforcement during installation shall be considered in the design of D-type anchor bars
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From the perspective of whether it is convenient for the installation of curtain wall keel, the slot embedded parts and the adapter of curtain wall keel are connected by T-bolts
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⑥ The compound form of the above forms
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1.3 embedding method of embedded parts
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Expansion bolts and reamed bolts shall not be used for the rear anchor connection of structural members under tension and edge shear (edge distance C ＜ 10hcf effective anchorage depth of anchor), structural members under tension and shear composite stress and non structural members of lifeline engineering.
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1.1 embedded parts embedded parts are components pre placed (buried) in the structure, that is, components made of steel plates and anchor bars left in the structure during structural pouring
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The price of slot embedded parts is about half of that of flat embedded parts
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Generally, the efficiency of processing a groove embedded part is three times that of processing a flat embedded part
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Disadvantages of groove embedded parts compared with plate embedded parts: the most obvious disadvantage of groove embedded parts compared with plate embedded parts is that the bearing capacity of groove embedded parts is much smaller than that of plate embedded parts
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The weight of a grooved embedded part is about 2kg, plus two T-bolts
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Embedded parts can be divided into upper buried type, side buried type and lower buried type according to their position on the main structure
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F-type embedded parts are suitable for parts requiring lightning protection（ 4) The size of the embedded plate shall consider the needs of the structural form of the curtain wall in the design
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In particular, the state has expressly stipulated that expansion bolts are not allowed to be used at the tensile parts, so post patched embedded parts shall not be used as far as possible
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There is no need for welding on site, so the installation is very convenient
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In this way, the three-dimensional adjustment of curtain wall keel installation is realized, and the installation is very convenient
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In addition, due to the small volume of slot embedded parts, when the main structure is a thin plate structure, only slot embedded parts can be used instead of flat embedded parts
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The connection strength between embedded parts and the main body directly determines the safety of the whole curtain wall, which must be strictly controlled
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Among them, the lower buried type has unfavorable stress and should be used carefully
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Comparison of advantages and disadvantages between groove embedded parts and flat embedded parts groove embedded parts is a common form in curtain wall construction
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Since the installation quality of post patched embedded parts is greatly affected by the site construction conditions and personnel, it is not easy to control, and often can not reach the design index
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1、 Classification and composition of embedded parts embedded parts are divided into embedded parts and post embedded parts according to their formation sequence, in which embedded parts are divided into claw embedded parts and groove embedded parts
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Because the construction workers do not know the importance of the main reinforcement very well, they occasionally saw off the main reinforcement of the main structure in order to bury the flat plate embedded parts, which will bury potential safety hazards to the building
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Therefore, when the span of curtain wall is large or the curtain wall surface is far from the structural surface, the grooved embedded parts are not suitable, and only flat embedded parts can be selected
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The weight of a flat embedded part is about 6kg, and the price is about 60 yuan
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C
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The anchor bar and the metal groove can be made into a whole or welded
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The specification, diameter, length and weld thickness of anchor plate shall be calculated and determined according to its stress (tension, shear and bending), including the minimum thickness of anchor plate, the spacing of anchor bar and the distance from anchor bar to the edge of anchor plate, The bearing capacity of embedded parts and the anchoring bearing capacity of connectors and main structure must be confirmed through calculation or physical test, which meets the specification requirements
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From the perspective of economy, the price of groove embedded parts is cheaper and saves the project cost
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The price of a set of grooved embedded parts is about 25 yuan
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There is only one row of anchor bars for slot embedded parts, and the channel steel of slot embedded parts is small, which is not easy to interfere with the reinforcement of the main structure, and the construction period is short, which greatly improves the construction progress
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The plate embedded parts can also realize three-dimensional adjustment, but they need to be welded for fixation after adjustment, which not only increases the difficulty of on-site construction, but also increases the possibility of fire
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Advantages of groove embedded parts compared with flat embedded parts: 1
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1.1.2 embedded plate with reserved slot type embedded parts
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Because it has more advantages compared with flat embedded parts, the application of groove embedded parts in curtain wall engineering is gradually increasing
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According to different panel materials, building curtain walls are divided into three categories: glass curtain wall, metal curtain wall and stone curtain wall
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However, the construction party often pays insufficient attention to the special design of embedded parts, even ignores the specification requirements, and hastily arranges the civil construction embedding
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In addition to bearing the dead weight load, the curtain wall also bears the influence of wind, earthquake and other loads
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The adapter and T-shaped bolt are connected with long holes in the vertical direction, and the adapter and curtain wall keel are connected with long holes in the direction perpendicular to the curtain wall
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At present, it has been localized and has formed a series
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As shown in the figure
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1.1.4 the metal groove of groove type embedded parts can be made of steel plate bending, castings and forgings
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1.2.1 several construction methods of post embedded parts ① ordinary expansion bolt fixation ② chemical anchor bolt fixation ③ penetration bolt (stud) fixation ④ hoop steel plate welding (usually used for column or beam) ⑤ post construction civil structure and embedded embedded parts
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The length of groove type embedded parts commonly used in construction is 300mm, and the length of anchor bar is 100mm or 60mm
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This form of embedded parts has the advantages of small volume and convenient construction
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This lack of scientific design and blind embedding not only causes a large number of fees for embedded parts, It also increases the potential safety hazards of curtain wall（ 2) The technical requirements for post embedded parts shall not only consider the performance differences of various bolts, but also consider the properties of base materials, stress properties of anchor connections, types of connected structures, no seismic fortification requirements and other factors
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1.1.1 the anchor bar of ordinary claw embedded parts is formed by welding the anchor plate, and the anchor bar can be made into straight, curved and hook type
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1.1.3 claw embedded parts (a ~ F are several common types, as shown in the figure)
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The grooved embedded parts are connected with the curtain wall keel adapter through the T-shaped bolt that can slide freely and horizontally in its notch
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From the perspective of construction difficulty, the volume of groove embedded parts is small and the construction is very convenient
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No matter which type of curtain wall, the connection between its bearing structure system and the main structure of the building is usually realized through embedded parts or post added anchors
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The design value of tensile bearing capacity of groove embedded parts is 32KN, the design value of shear bearing capacity is 23kn, and the design value of tensile bearing capacity of plate embedded parts is 140kn, The design value of shear capacity is about 55kn
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2、 Embedded parts design 1
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The following points shall be paid attention to in the design of embedded parts: (1) the size and position of anchor bars and embedded plates of embedded parts shall be designed in strict accordance with code for glass curtain wall engineering (JGJ102-2003) and code for design of concrete structures (GB50010-2002)（ 2) Note that the length of the anchor bar shall not exceed the structural size (such as beam thickness) to avoid the anchor bar exposed outside the structure（ 3) Rebar should be used for type A and B anchor bars in claw embedded parts
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Post patched embedded parts can only be connected with the main structure through expansion bolts and chemical anchors
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In time, it can also be welded like ordinary embedded parts under the condition of large position error of embedded parts, with great flexibility
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Pay attention to the technical requirements of embedded parts (1) the technical requirements of embedded parts are the special design content of curtain wall that the builder must pay attention to
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Therefore, whether the connection between embedded parts and the main structure of the building is reliable and durable is directly related to the structural safety and service life of the curtain wall
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From the perspective of production and processing, the processing technology of groove embedded parts is simple and the quality inspection is convenient
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