ATTEN: Manager Liu
ADD: Longhua Development Zone, Jing County, Hengshui City, Hebei Province
23 steel beam and wall, column joints are designed and constructed to facilitate the connection between composite beam and core tube. Because the outer wall of core tube is thicker, steel columns are embedded in the position of composite beam of outer wall of core tube. The ultimate bending strength of steel columns in wall is not less than half of that of steel in composite beam. In order to ensure the transfer of bending moment (see Figure 4 for details), because there are many such steel columns in the wall plane, it can also have a better restraint effect on the wall. When the composite beam is connected with the concrete filled steel tubular coiled column, the steel stiffening ribs in the steel column are used, which are in the same inch, and the supporting steel bundles with perforated beams on the steel column are used. In order to avoid too much weakening of the steel column, the steel bundles at the end of the beam can be used with two parallel reinforcements when necessary. In the design and construction of the three-arm floor, it is necessary to control the displacement and comfort of the super-high-rise building with the extension arm, so as to minimize the stress concentration (Fig. 5, Fig. 4, the connection between the composite beam and the wall, Fig. 5, the connection between the composite beam and the concrete filled steel tube cockroach column, and the connection between the composite beam and the concrete filled steel tube cockroach column (the steel structure design of Changfu Jinmao Building). It can make better use of the "tension and compression" mechanical characteristics of the outer column to provide more flexural performance for the structure. The extension arm is usually used together with the waist truss. However, during the trial calculation of this building, it is found that the effect of the waist truss is not clear (the outer ring beam of this building is a steel-reinforced concrete composite beam, and the section of the beam is large, so the stiffness and bearing capacity can be provided without the vehicle. The design performance target of the waist truss is small earthquake elasticity and moderate earthquake unbending. Because it is herringbone truss, it will produce considerable bending moment at the support of the extension arm (the intersection of the extension string and the core tube). If the chord truss is only made of steel components, it needs very thick steel plate. It is difficult to construct in practice, so the steel-framed composite beam is adopted. As an extension chord, the support is equipped with a steel bow to resist pyridine bending moment. Figure 6. When the extension chord is in the wall, the 31-arm problem and its solution (Changfu Jinmao Building steel structure design) are solved. The north-south and east-west chords of the extension arm are respectively lengthened, while the section of the extension chord is wider and passes through the outer wall of the core tube, which is equivalent to the section width norm. In general, the friction bond between steel plate and coagulator is not very good. If not solved here, the shape of the wall is used to weld 22@150*150 studs on the surface of steel plate (detailed figure 6).
From the point of view of mechanics, the design value of shear capacity of studs is NvC=0.7Asr"=95.5kN (stud material performance grade 4.6), while the ultimate bearing capacity of concrete sections in the range of 150*150 is =0.2fcbh=123.75kN (in the form of 6o0). This basically enables the studs to transfer the shear force of the upper concrete wall to the extensor chord bar. Then the transmission is continued downward through the extension arm string web. The horizontal distribution of stirrups and walls of concealed beams can also transfer the shear force from the upper part to the lower part, and consolidate the overall coordinating workability. Figure 7 The sketch of the end joints of the extensors (the steel structure design of Changfu Jinmao Building) is at the end of the extensors (the connecting part with columns or walls). Because of the large number of steel bundles of composite beams and the wider extensors, perforated plug welding is adopted. In order not to weaken the members too much, and the enjoyment of the section of the column steel tube can also have a good anti-reduction ability of the section (detailed drawing construction stage, because the stress level of the core tube and the outer frame column is different, the thickness and the shrinkage characteristics of the members are different, there will be a difference in deformation, because the stiffness of the extension arm is huge, a little difference in deformation will produce a larger internal. Force, therefore, if the extension arm works too early, it will inevitably produce internal force, which we do not want to see, but hope that the extension arm will only bear the relevant response under the horizontal action, so it is particularly important to keep the extension arm in the "no work" state in the construction stage, until the deformation difference is completed or most of it is completed, the extension arm will "work". This is more in line with the original intention of setting the extension arm. A good force method is not to install the extension arm web bar (chord bar must be constructed in the same way for pouring floor slab and upper supporting formwork). Considering the difficulty of hoisting, this building adopts the method that other components are in place at the same time, but not welded.
Open a long strip hole on the web of the web of the web of the web of the web of the web of the web of the web of the web of the web of the web of the web of the web of the web of the web of the web of the web of the web of the web of the web of the web of the web of the web of the web of the web of the web of the web of the web of the web of the web of the web of the web of the web of When it is necessary to let the arm "work", the bolt is loosened and then the arm is welded to make it "work".