Hoisting construction technology of steel structure in structural engineering.

1. Hoisting process: positioning → elevation determination → anchor bolt inspection → elastic line → installation of main steel members (such as steel columns and beams) → installation of secondary steel structures (such as purlins) → painting → completion.

2. The hoisting construction unit shall first retest the foundation, including the exposed length of the anchor bolt, the displacement deviation of the center line of the anchor bolt from the baseline, the spacing of the anchor bolt, and the elevation of the foundation. The hoisting can only be carried out after unqualified handling. At the same time, in order to effectively control the installation elevation of steel members, the visible position elevation is also drawn on the section of the members in advance, so that the elevation can be fine-tuned and corrected during installation. The following is an example of steel column hoisting in steel structure industrial workshop:

(1) Install the steel column on the basis of passing the retest. First, bind the column with a single steel wire rope, and choose the lifting point at the length 1/3 from the column end. The column is hoisted by rotating method, and the steel column is hoisted to the installation position. Draw an elevation line of +500mm at the bottom of the steel column for control during hoisting. ⑵ Push the column to align the bolt holes of its bottom plate with the foundation anchor bolts, and make small-scale adjustment repeatedly according to the situation until all the embedded anchor bolts are aligned with the bolt holes, and then slowly lower the component. Pay attention to ensure that each embedded anchor bolt of the column enters the bolt hole during the process to ensure that the column falls vertically. (3) When the whole column basically falls on the foundation, adjust the center line of the column and the foundation positioning axis. The adjustment of the center line is mainly through aligning the center line of the foundation with the center line that has been divided on all sides of the column with a spirit level (which has the dual function of measuring horizontal and vertical), and then adjusting it repeatedly. (4) Adjust the elevation of the column. Because the column falls on the composite edge in advance, the elevation only needs to be fine-tuned. Check whether the 500mm line drawn on the column in advance is consistent with the actual elevation through the level gauge, and adjust the elevation with the shim. 5] Verticality control of the column: ① Draw the center line on the visible surface of the column in advance, and then use theodolite to adjust the verticality of the column in two mutually perpendicular directions. ② The verticality of the column is controlled by measuring the distance between the inside of the column and the control line of the building. (3) The adjustment of column elevation, axis and verticality deviation are interrelated, and the correction work can only be taken into account when all standards are met.

Second, the steel member hoisting points

1. It is very important to choose lifting points when hoisting, and the selection of lifting points should balance the components as much as possible.

2. The choice of station in hoisting determines the tonnage and hoisting cost of crane, which is also a difficult point in hoisting. The crane station should be determined reasonably, and it should not be too close to the building or too far away from the building, otherwise it will increase the difficulty of hoisting components. 3. The steel wire rope should be selected reasonably when hoisting. When lifting, the smaller the angle between the wire rope and the horizontal plane, the more labor-saving the traction and the larger the lifting space. However, the smaller θ is, the greater the tension on the wire rope is. This is a contradictory unity. When choosing the hoisting tonnage of the crane, the hoisting height can be improved by this method. It is very important to adopt a reasonable θ angle and choose a suitable wire rope, which can neither be pulled too hard nor bear too much load.

For example, for heavy steel members with high positioning height, the method of double-machine lifting can be adopted, that is, the method of standing at both ends of double lifting points, which can reduce the load of each crane. During hoisting, two machines are hoisted at the same time, one of which is the main crane (usually a large tonnage crane) and the other is the auxiliary crane. When the steel structure is hoisted in place, the auxiliary machine shall be dismantled and hoisted by the main machine alone. When the steel structure is initially corrected and fixed, the position deviation meets the relevant requirements.

When hoisting large steel members, if conditions permit, single mechanical equipment should be considered first, and for some construction that is difficult to hoist under narrow conditions, on-site mechanical equipment should be considered; At the same time, for the safety of the hoisting process, necessary measures should be taken to stabilize and strengthen the components in the hoisting process. For example, in the construction of steel members in the material warehouse of our cement plant, truck cranes and tower cranes are used for hoisting. After the steel members are hoisted in place, they are fixed by scaffolding platforms. This method is suitable for hoisting technology with high hoisting height and many components. In addition, for heavy steel members, "manual sliding hoisting method" can also be used to hoist heavy steel members, which can be used to hoist heavy steel members in general narrow places.

The steel structure is light in weight, high in strength and good in seismic performance, which is convenient for industrial production. It is an energy-saving, environment-friendly and recyclable building structure, which meets the requirements of sustained and healthy economic development and has great room for expansion. The hoisting of steel members in different projects has its own characteristics, and the hoisting construction of new projects is constantly emerging. Many installation skills need to be further discussed with you.