Views:14 Author:Site Editor Publish Time: 2020-08-10 Origin:Site
1. Understanding of construction engineering
The upper structure of this project is a steel structure, and the pillars are steel columns. The design drawings require anchor bolts to be embedded in the foundation construction stage for connection with the upper steel columns. This method has the characteristics of convenient construction and superior connection performance, but it also has strict requirements on the accuracy of construction. The embedding accuracy of anchor bolts directly affects the installation accuracy of the steel column and even the installation accuracy of the entire steel structure project. Small errors in the burying of anchor bolts may cause serious consequences during construction. This work needs to be taken seriously. To ensure the smooth progress of construction, the construction plan, construction steps and matters needing attention are now The description is as follows:
1. Calculation of the tensile strength of anchor bolts The tensile strength of the anchor bolts is the tensile strength of the round steel itself, the size is equal to the cross-sectional area multiplied by the tensile strength design value of 140MPa, and the value obtained is the anchor bolt at the time of design The allowable tensile bearing capacity.
2. Anchor bolt construction process:
Measure and pay off → pier steel bar binding → pier template installation → positioning plate installation and fixation → bolt group installation review → bolt welding fixation → concrete pouring, bolt review → finished product protection.
3. Construction method
(1) Determination of axis and elevation
In accordance with the requirements of the construction drawings, at the pre-embedded anchor bolts of the piers, the axis line positioning is required to determine its horizontal position and elevation. Draw the bolt cross center line mark on the top of the installed pier template as the initial installation position of the bolt installation. According to the marked position on the template, an independent bolt group mounting bracket is set up with steel pipes and fixed to determine the elevation of the positioning steel plate.
(2) Positioning template in place
In order to prevent the displacement of the anchor bolts when concrete is poured, positioning templates are used to strengthen the fixing bolts when anchor bolts are buried in this project. Place the positioning plate on the horizontal support of the steel pipe so that the crosshairs of the positioning plate (the template with vertical crosshairs drawn on it) are aligned with the template logo, and initially fixed. Check whether its position is appropriate, otherwise make partial adjustments.
(3) Install bolt group
Put the anchor bolts into the short column in advance, insert them into the reserved holes of the positioning template, fix the upper part of the screw with nuts up and down, and check the mutual dimensions of the single set of bolts while tightening. Adjust the elevation to the same level, insert the positioning template, and screw a nut on the top of each bolt to fix the mold.
(4) Fixing of anchor bolts
The first step is to fix: use short steel bars as the support of the foundation beam, stand on the cushion of the platform, and weld it firmly to the foundation beam to prevent the foundation beam from shifting;
The second step is to fix: each anchor bolt welds the short steel bars and makes the bolt support stand on the cushion. After the bolts are finally fixed, the bolt support feet are welded with the platform mesh steel bars to fix the anchor bolts to prevent construction Displacement.
The third step is to fix: determine the position of the positioning stirrups, which are used to assist in fixing the anchor bolts.