ATTEN: Manager Liu
ADD: Longhua Development Zone, Jing County, Hengshui City, Hebei Province
Generally, the size of the opening is 8 mm larger than the diameter of the reinforcing bar, that is, 36 mm on the reinforcing bar column with a diameter of 28 mm. Generally, this kind of steel bar openings are not allowed to be cut on site in the construction drawings design instructions of Taizhou Cultural Center Museum. Moreover, after the cross pillar is formed, there is no room for drilling machine operation. Therefore, the God connection method requires high positioning requirements for reinforcement. In the deep modeling, it is necessary to locate the beam and reinforcement in all connection directions in the joint area, and then open holes in the web. In the museum project of Taizhou Cultural Center, there are not less than dozens of reinforcing bars in one joint, which has a large workload. The advantages of perforated connections lie in the following: first, steel bar penetration meets the requirements of concrete specifications. Secondly, the separation of steel bar and steel bar has no effect on the force of steel bar itself. The lack of Beijing is due to the high requirement of positioning accuracy of the first steel bar, which often shows that the positioning of the binding steel bar in concrete construction is not consistent with the positioning of the opening of the steel bar in the steel bar lofting. Secondly, the through steel bar is generally tied up thick and through as a whole, and the hole location restriction is difficult to penetrate.
The general treatment method is to take a section through the steel column first and then butt-weld with the whole binding steel bar. The construction time is more exact. 2.2 stiff steel column is connected with the bracket or the stiffening plate is welded with the steel sheet. H-shaped bracket is installed on the stiff steel column, the main reinforcement of the beam is welded with the bracket flange, and the bracket flange is welded out of the cross column inside the bracket flange. The connection of steel bar and steel column bracket in the Museum of Taizhou Cultural Center indicates that the bracket elevation positioning should be paid attention to when deepening the design of the bracket. Field welding should avoid back welding, so the arrangement of main reinforcement of concrete beam and upper flange of H-shaped bracket. Therefore, the height of the soup plate on the bracket is equal to h-a-d. H is the top elevation of concrete beams, A is the thickness of protective layer of beams and D is the diameter of reinforcing bars. The cross-sectional height of the bracket is equal to H2a-2d+t. H is the height of concrete section and t is the thickness of H-shaped corbel mat. There is also a point to be noted when deepening. Generally, reinforcing bars are crossed vertically and horizontally, and reinforcing bars have a problem of adding each other. Therefore, when deepening, it is necessary to consider that the ratio of horizontal bracket to height is higher than that of vertical bracket or the diameter of reinforcing bars is higher than that of vertical bracket.
Secondly, the collision between the stirrup and the main reinforcement on the column and the newly added bracket is treated. The hoop treatment is relatively simple. It opens directly on the webs of brackets, and then the hoop passes through. In general, the best way to arrange the main reinforcement of concrete is to approach the corner of the column as close as possible at the beginning of the arrangement of the main reinforcement. When a few of them collide with the bracket flange, they can be welded with the connecting plate or connected with the reinforcement sleeve. Thirdly, the length of bracket is determined. The specification stipulates that the length of weld between steel bar and bracket is not less than 5 days, so the length of bracket should be more than 5 days. First, the positioning accuracy of bracket is lower than the other two ways, and the field adjustment ability is strong. The positioning requirements of steel bar binding are also lower than those of the other two methods. Its shortcomings: First, the bracket has a certain impact on the main reinforcement of concrete. It is necessary to adjust the position of the main reinforcement from the bottom of the column, otherwise it will collide with the bracket too much. Secondly, in general, on-site welding should avoid back welding, so the bracket connection is not suitable for multi-row steel bar connection and needs to cooperate with other connection modes.
3.2.3 The stiff steel column is equipped with a steel sleeve and a steel bar mechanical connection concubine tube, also known as a steel bar joint, which is used to connect the steel bar and has a connecting piece corresponding to the screw thread. The end of the reinforcing bar is processed into straight threads by rolling process, and the two reinforcing bars are connected with each other by corresponding connecting sleeves. Its principle is to strip part of the longitudinal and transverse ribs to be connected to the end of the steel sheet by cutting, then roll them directly into ordinary straight threads, and then connect the concubines with special straight mule-shaped steel bars to form the connection of steel bars. (See Fig. 5).