Technical points of steel structure installation

1 positioning measurement

Retest the horizontal elevation, axis and column spacing of the foundation according to the design data. The cross lines of the vertical and horizontal axes shall be marked on the top surface of the foundation as the positioning datum for installing the column.

2 column installation

In order to eliminate the influence of errors in column length manufacturing on column elevation, before hoisting, measure 1m downward from the upper plane of bracket as the section of theoretical elevation, and mark obvious marks as the benchmark for adjusting column elevation. On the upper surface of the column base plate, mark the cross line of the vertical and horizontal axis passing through the column center, which is used as the benchmark for the installation and positioning of the column. During installation, the cross line on the column shall coincide with the cross line on the foundation. Firstly, the elevation of the column shall be corrected with the level according to the mark at the theoretical elevation on the column, and then it shall be padded with cushion blocks and the anchor screws shall be tightened. Then use two theodolites to correct the verticality of the column from the two axis directions. After meeting the requirements, use double nuts to tighten the bolts. For the column of single unstable structure, temporary protection measures with wind cable can be taken. For columns designed with inter column support, inter column support can be installed to enhance structural stability.

3 crane beam installation

The crane beam shall be inspected before installation, and can be installed only when the deformation does not exceed the limit. After the crane beam is hoisted in place, it shall be connected with the bracket with bolts in time, and the connecting plate between the upper edge of the beam and the column shall be connected. It shall be adjusted with a level and Jingwei instrument. After meeting the requirements, the bolts shall be tightened.

4 roof beam installation

Before the roof beam is assembled on the ground, the components shall be checked. When the deformation of the components does not exceed the limit, the friction surface of high-strength bolt connection is free of sediment and other sundries, and it is confirmed that the friction surface is flat and dry, it can be assembled on the ground. During assembly, the components shall be padded with oil-free sleepers, and both sides of the components shall be supported with wooden bars to enhance stability. The assembly of roof beam takes two columns as a unit, and the unit shall be inspected after splicing:

① Straightness of beam;

② The spacing dimension of bolt holes connected with other components (such as columns). After the adjustment and inspection meet the requirements, tighten the high-strength bolts.

5 installation of accessories

Roof purlin and wall purlin shall be installed at the same time. Before purlin installation, the deformation of members shall be checked. If it exceeds the limit, it shall be treated to remove oil and sediment on the member surface. Several purlins shall be hoisted together as a group, and the purlin slope shall be checked after the installation of one span. The straightness of purlin shall be controlled within the allowable deviation range, otherwise it shall be adjusted by connecting bolts (add cushion blocks if necessary).

6 re inspection, adjustment, welding and paint repair

After hoisting, recheck and adjust all components. After meeting the design requirements, conduct on-site welding and repair the damaged parts of component paint.