Steel structure engineering: fabrication and installation works

Steel Structure Installation Procedure

After completing the preliminary fabrication and processing, steel structures proceed to the installation phase. Xingyuanyi adheres to the following standard procedures for steel structure construction: foundation work—pre-embedding of anchor bolts—erection of steel columns—installation of steel beams—installation of purlins and horizontal bracing—installation of exterior wall panels—installation of the roofing system—final acceptance.

Our installation projects encompass steel‑structure workshops, steel‑structure platforms, steel‑structure buildings, steel‑structure canopies, roofing and cladding works, steel‑structure additions and renovations, steel‑structure glass houses, prefabricated modular buildings, as well as multi‑story and high‑rise steel‑structure residential and commercial buildings.

Xingyuan Yi is equipped with professional installation machinery, including steel‑structure hoists, cutting machines, electric welders, hand drills, and a variety of other advanced tools.

The company boasts an experienced installation team, with over 200 skilled professionals, all of whom possess solid expertise in steel structure installation.

During the construction process, we rigorously adhere to the construction organization plan, strengthen on-site management, and continuously enhance the skills and safety awareness of our workforce, thereby ensuring both project quality and construction safety.

Installation Process Standard for Steel Structure Engineering (I)

1 Scope
This process standard applies to the fabrication and installation of steel structures in general industrial and civil construction projects.

2 Construction Preparation

2.1 Equipment and Major Tools

Equipment: Depending on the component weight and site conditions, select a gantry crane, truck-mounted crane, or crawler crane, among others.
Main tools and equipment: lifting slings, electric welding machine, timber blocks, shims, wrenches, crowbars, torque wrenches, jacks, straightedges, tape measures, etc.
2.2 Materials and Semi-finished Products

Steel components: Their specifications and fabrication quality shall comply with the requirements of the design and construction codes.
Connection materials, such as welding electrodes and bolts, shall be accompanied by certificates of quality and shall comply with current national standards.
2.3 Working Conditions

Verify the incoming quantities against the component schedule and inspect the certificates of conformity and relevant technical documentation.
Inspect the components for damage or deformation during transportation and storage; if any is found, they must be straightened, have their anti-corrosion coating repaired, and undergo re‑inspection.
Verify that the assembled steel components meet the quality standards.
The installation site’s foundation shall be solid and provide sufficient working space for equipment and personnel.
Confirm that the preceding process has completed acceptance, handover, and inspection procedures.
3 Operating Procedures

3.1 Process Flow
Work preparation → Component installation → Connection and fixation → Inspection and acceptance

3.2 Assembly of Steel Roof Trusses (Steel Skylight Frames)

The roof truss configuration is based on Figure 9-46 of the “Construction Manual for Steel Structures.”
Place half of the roof truss on the assembly platform, level it, and tack weld it; then complete the welding in sequence.
For roof trusses with low lateral stiffness, post-weld reinforcement is required; after turning the component over and rechecking its dimensions, welding should be continued (see Figures 9-47 and 9-48).
When roof trusses exhibit twisting or kinking, they shall be straightened using mechanical means or flame treatment.
When the camber and the span conflict, the camber value shall prevail.
If the node angle or dimensions do not meet specifications, they should be repaired promptly.
Both vertical and horizontal formwork must be securely supported to prevent settlement that could compromise the arching effect (see Figures 9-49 to 9-51).
3.3 Steel Column Assembly

Multi‑section columns can be assembled on the ground and then lifted into place as a whole; the number of sections to be assembled must be determined based on the crane’s lifting capacity.
Provide the corresponding platforms and molds according to the column cross-section.
After aligning the centerline of each column, use a plumb line stretched across three sides when assembling multiple columns, and be sure to control verticality.
The misalignment of the node flange plates shall be corrected to within the allowable tolerance, using a chain hoist and ear plates for alignment during butt jointing.
The node shall be restrained by a connection plate, which is to be removed after welding has cooled.
After welding is completed, the workpiece is turned over, leveled, and its dimensions are checked; the restraint plates and lug plates are then cut off.
3.4 Steel Beam Assembly

Solid-web steel beams may be assembled using either horizontal or vertical splicing, with the following procedure:
Component positioning → Assembly table alignment → Leveling → String line layout → Ordinary bolt positioning → High-strength bolt installation → Initial tightening → Final tightening → Dimension recheck
Light steel‑structure steel beams have relatively low lateral stiffness; during lifting, multi‑point rigging should be employed to prevent deformation.
3.5 Assembly of Three-Dimensional Arched Trusses

The elevation of the chord members can be controlled using the water‑pipe communication method.

Process flow:
Cradle fabrication → Overall assembly and positioning → Alignment and inspection → Butt welding → UT inspection → Post-weld alignment → Painting → Final inspection

Select appropriate lifting equipment and establish a horizontal final assembly platform.

After passing inspection, the cradle is used for truss assembly.

During assembly, jigs are used to constrain the joints and control post-weld distortion.

The steel pipe joints employ an internal liner‑pipe groove configuration, with the gap adjusted by a pre‑tightening device.

Installation Process Standard for Steel Structure Engineering (Part II)

3.6 Steel Column Installation

3.6.1 Types of Steel Columns

By number of stories: single-story and multi-story steel columns.
Classified by length: long columns and short columns.
According to cross-sectional shape, they are classified as U-shaped, I-shaped, circular, II-shaped, III-shaped, and others.
3.6.2 Selection of Lifting Points
The location of lifting points shall be determined comprehensively based on the steel column’s shape, cross-section, length, and the performance of the lifting equipment.

Typically, steel columns exhibit good elasticity and rigidity, allowing for single-point vertical lifting with lifting lugs positioned at the column top; this ensures the column remains plumb, facilitating alignment and correction. When constrained by crane boom length, lifting points may instead be located at one-third of the column height, employing inclined lifting; in this case, the column will be tilted, increasing the difficulty of alignment.
For slender steel columns, to prevent deformation, two-point or three-point lifting should be employed.
If no dedicated lifting lugs are provided, when using wire ropes for direct slinging, please note:
For I‑shaped and U‑shaped columns, the four corners shall be protected with corner guards—either semi‑circular steel tubing or internal angle steel—to prevent the wire rope from being cut.
When the lashing points are located on I‑shaped columns, reinforcing stiffener plates shall be provided to prevent local compressive deformation; when lifting lattice columns, support rods shall be installed at the lashing points.
3.6.3 Lifting Method
For large steel columns in heavy‑duty industrial buildings, single‑crane, dual‑crane, or triple‑crane lifting methods may be employed, depending on the available lifting equipment and site conditions.

Rotational Method: While lifting the hook, the crane simultaneously rotates, causing the steel column to pivot around its base and be hoisted (see Figure 9-60 in the Manual).
Sliding Method: The crane lifts the hook, causing the base of the steel column to slide as it is hoisted. To reduce friction, a sliding track should be laid beneath the column base (see Figure 9-61 in the Manual).
Delivery Method: When lifting with two or three cranes, the secondary crane’s hook is positioned at the lower portion of the steel column. It works in tandem with the main crane to lift the column, then moves laterally or swings to position the column foot above the foundation. Subsequently, the secondary crane unloads, and the main crane places the column into its final position (see Figure 9-62 in the Manual).
Precautions for dual‑machine or multi‑machine lifting:
Preferentially select cranes of the same type.
Distribute the load according to the crane’s capacity.
The load on each machine should not exceed 80% of its rated lifting capacity.
During operations, coordinated movements are essential; an iron beam should be used to maintain boom balance, and the tilt angle should be kept small to prevent a single crane from losing stability and causing overloading of other cranes.
The command system shall be unified, and subordinate commanders must obey the overall commander.
3.6.4 Installation of Steel Columns in Light Steel Structures

Portal frame columns are typically tapered, with a larger cross-section at the top and a smaller one at the base, resulting in a relatively high center of gravity. After installation and securing, temporary bracing should be provided as needed to prevent overturning.
Anchor bolts at the column base shall be positioned using a reliable method (see Figure 9-89 in the Manual). Measure both the perpendicular leg and the diagonal length, and verify the bolt locations before and after concrete placement to ensure that the foundation dimensions and elevations comply with the design requirements.
Elevation adjustment, cross‑line alignment, verticality control, and installation procedures shall follow the standard steel column erection process.
Installation tolerances shall be in accordance with the national standard “Code for Acceptance of Construction Quality of Steel Structures” GB 50205–2001.
3.6.5 Steel Column Alignment
The alignment checks include: column base elevation, longitudinal and transverse crosslines, and column verticality.

Correction of Single-Story Steel Columns
Column base elevation adjustment: Based on the actual length of the steel column, the flatness of the column base, and the distance to the top of the corbel, the foundation elevation is adjusted to ensure the desired elevation of the corbel top. Adjustment nuts may be used to control the elevation of the base plate, achieving an accuracy of ±1 mm; any voids beneath the column base shall be filled with non-shrinkage mortar. The strength and stiffness of the anchor bolts must be verified.
Alignment of the crosshairs: Align the side punch marks on the base plate with the foundation’s crosshairs to ensure coincidence. During alignment, keep the crane hook engaged and lower the component slowly to the specified elevation. To allow for tolerances, the bolt holes may be slightly oversized and secured by welding a top pressure plate.
Column verticality correction: The cable‑tensioning method is employed, with two theodolites positioned at 90° to each other for observation. Column base bolts are adjusted to achieve alignment; after correction, the upper nuts are tightened, and final fixation is completed following a recheck to confirm accuracy. Refer to Table 1 for the specified tightening torque of anchor bolts; either double nuts or a nut welded to the bolt shank may be used.
Table 1: Tightening Force of Anchor Bolts

Alignment of Steel Columns in High-Rise and Super‑High-Rise Steel Structures
Key control items: elevation, axis alignment, and verticality.
Column alignment on the first floor is performed in the same manner as for single-story structures. Note that the reinforcement around the steel‑concrete composite columns must be carefully arranged to facilitate construction operations.
Upper-level column elevation control:
Installation using the relative elevation method: After the steel column is positioned, connect the lug plates with high-strength bolts (without fully tightening them). Use a pry bar to make fine adjustments to the gaps, then measure the elevation at the top of the column. Once the elevation meets the requirements, drive in steel shims to restrain downward movement, ensuring that the elevation deviation remains within 5 mm.
Using the elevation of the first-floor column tops as the datum, calculate the control lines for each column top. If the deviation exceeds 5 mm, use low-carbon steel shims for adjustment.
Cross‑line alignment: The upper and lower column crosslines should be aligned as closely as possible. If misalignment occurs, insert shims 0.5–1.0 mm thick on the side of the connection lug plate and adjust by tightening the large hexagon bolts; each adjustment should not exceed 3 mm, and significant deviations should be corrected in 2–3 stages. Note: The positioning axis of each column section must be transferred from the ground control axis; do not use the axis of the lower column section.
Verticality Correction:
Step 1 (Cable‑free wind‑up correction): Drive steel wedges into the side of the column where it is inclined, or use jacks to adjust the column top’s axial offset to zero, then tighten the high‑strength bolts (see Figure 9‑64 in the Manual). The bolt holes in the temporary connection lug plates shall be 4.0 mm larger than the bolt diameter to accommodate manufacturing tolerances.
Step 2 (Post‑Beam‑Installation Alignment): After installing the upper, middle, and lower beams, perform a final alignment using cables, jacks, steel wedges, or chain hoists (see Figure 9‑65 in the Manual). Refer to Table 9‑59 in the Manual for weld‑shrinkage values.
Permissible deviations for the external dimensions of single‑story and multi‑story steel columns are specified in Tables 4‑179 and 4‑180 of the Manual.
3.7 Installation of Steel Roof Trusses

3.7.1 Lifting and Reinforcement
Steel roof trusses have poor lateral stiffness and must be reinforced before lifting.

Single‑machine lifting (with one or more attachment points and an iron beam) is often used to reinforce the bottom chord.
When using a two-crane lift, the top chord shall be reinforced.
3.7.2 Binding Requirements
Lifting points must be located at the truss joints to prevent bending and deformation of the member at the lifting point.

3.7.3 Positioning and Securing

After the first roof truss is in place, guy wires should be installed on both sides for stabilization; if wind bracing columns are provided at the ends, they may be used to secure the truss.
After the second roof truss is in place, use a truss adjuster to check and correct its verticality, then secure both end supports (by bolting or welding). Next, install the vertical bracing and the horizontal bracing. Once everything has been verified, designate this section as a reference unit; subsequent installations shall follow this procedure.
3.7.4 Combined Lifting
To minimize high‑altitude work, the skylight frame can be preassembled on the roof truss at ground level; during tying, position the frame between the two lifting slings to ensure overall stability (see Figures 9‑66 and 9‑67 in the Manual).

3.7.5 Verticality Correction

Theodolite method: Place the theodolite at the top of the column, offset by a distance a from the axis; establish a corresponding point on the opposite column. Extend a line from the midline of the roof truss by a distance a, ensuring that the three points lie on a straight line to verify verticality (see Figure 9-67 in the Manual).

Plumb‑bob method: Stretch a continuous steel wire along one side of the bottom chord of the roof truss, mark a reference line on the top chord at an equal distance from its centerline, and use a plumb bob to verify alignment.

Installation Process Standards for Steel Structure Projects (Part III)

3.8 Steel Beam Installation

3.8.1 Installation of Steel Crane Girders

1. Lifting Method
The optimal solution shall be determined comprehensively based on the crane girder’s weight, the crane’s lifting capacity, site conditions, and project schedule requirements.

Before lifting the roof structure: single‑crane lifting, dual‑crane synchronized lifting, or a pulley system rigged to the columns may be employed (provided the columns have been structurally verified and equipped with guy wires), with the other end assisted by a crane. For makeshift lifting methods, a guide rope must be used to pull the beam clear of the column corbels, ensuring a smooth lift.
After the roof structure has been lifted into place, the optimal solution is to use a pulley system installed at the ends of the roof trusses or on the tops of the columns for lifting. This method requires a load‑capacity verification of the truss‑anchoring points or the column tops.
Lifting point configuration: It is recommended to use tool-type lifting lugs to ensure safety, reliability, and convenience.
2. Correction
The alignment work includes elevation, longitudinal and transverse axes (straightness and gauge), and verticality.

Elevation Adjustment:
After completing the lifting and installation of all crane girders within a single span, use a level (with an accuracy of ±3 mm/km) to measure the elevation at both ends of each girder. Calculate the weighted average of all measurements to obtain the reference elevation, determine the required shim thickness for each location, and then jack up the girder ends using jacks to insert wedge-shaped shims. Note: Elevation adjustments may be performed either before or after the roof‑truss installation.
Longitudinal and transverse axis alignment:
After installing the intercolumnar bracing to form a frame, transfer the correct axis from the column base to the top of the corbel and establish the design distance between the crane girder centerline and the axis. Stretch a continuous steel wire along the girder’s top‑centerline (or use a theodolite) and adjust the end‑reactions of each girder one by one. Taking advantage of the design feature whereby one end of the crane girder’s bottom flange has a circular hole and the other end an elliptical hole, perform fine adjustments with jacks and hand chain hoists, and finally secure the alignment with iron wedges.
Verticality Correction:
Suspend a plumb bob from the top flange of the crane girder and measure the horizontal distances from the plumb line to the web at both the upper and lower locations. By adjusting the shims, ensure that the upper and lower distances are equal, thereby guaranteeing verticality. This alignment procedure can be carried out concurrently with the alignment of the longitudinal and transverse axes.
Correction Timing:
Small and medium-sized crane girders: can be installed both before and after roof hoisting.
Heavy crane beams: Installation should be carried out after the roof trusses have been lifted into place, to prevent elongation of the bottom chords of the trusses from causing an increase in track gauge.
3. Permissible Deviation

Permissible deviations for the installation of steel crane girders are specified in Table 9-60 of the Manual.
Permissible deviations for the external dimensions of steel trusses are specified in Table 4-182 of the Manual.
3.8.2 Installation of Light Steel Structural Inclined Beams

1. Lifting Method
Portal frame inclined beams have large spans and low lateral stiffness; to ensure safety and quality and enhance efficiency, they should be assembled on the ground to the greatest extent possible and then lifted into place as a whole.

2. Lifting Method

A single‑machine, two‑point, three‑point, or four‑point lifting configuration may be employed, or an iron beam may be used to reduce the stress on the girder caused by the rigging.
For large-span members, a two-crane lifting method may be employed, with due attention paid to preventing lateral buckling of inclined beams.
3. Selection of Suspension Points

The lifting points for large-span inclined beams shall be determined by calculation.
For members with low lateral stiffness and high web width-to-thickness ratios, torsional damage should be prevented by carefully controlling the number of lifting points and ensuring synchronization and coordination during dual‑crane lifting operations. When necessary, a wire rope may be rigged between the main hooks of the two cranes to maintain a fixed spacing and prevent mutual traction.
4. Beam-Column Connections

The end plates for connecting inclined beams to steel columns can be arranged vertically, horizontally, or diagonally (see Figure 9-90 in the Manual).
Connections are typically made using high-strength bolts, which demand a high degree of installation accuracy.
5. Permissible Deviation
The allowable installation tolerances for steel structures of portal‑frame light‑weight buildings shall be in accordance with the national standard “Code for Acceptance of Construction Quality of Steel Structures” GB 50205–2001.

3.8.3 Installation of Steel Beams in High-Rise and Super‑High-Rise Steel Structures

1. Specialized fixture

The main beam is installed using specialized clamps, which should be positioned on both sides within 500 mm of the beam ends to prevent objects from falling from height.
2. Installation Sequence

A column typically supports 2 to 4 stories of beams, and in principle, vertical members are installed one by one from bottom to top.
For steel beams in the same column, installation shall proceed symmetrically from the mid-span outward toward both ends.
For steel beams spanning the same bay, install them in the sequence of upper-layer beam → middle-layer beam → lower-layer beam.
3. Measurement and Welding Control

When installing and aligning the main beams between columns, the columns must be braced apart, and measurements should be taken continuously to monitor alignment, with allowances for dimensional deviations and weld shrinkage.
Welding at column-to-column and beam-to-column connections shall be coordinated. Typically, the top-floor beam of a column section is welded first, followed by welding the beam–column joints of each floor from bottom to top. Column-to-column joints may be welded either prior to or after the other connections.
4. Installation of secondary beams

Secondary beams can be lifted in three-tiered sequences to improve efficiency.
5. Levelness Control

If the levelness exceeds the allowable tolerance, the primary causes are misalignment of the connection plates or errors in the bolt holes. This can be addressed by replacing the connection plates or by plug‑welding the existing holes and then re‑drilling them.

The allowable deviation in levelness at the two ends of the same beam is (L/1000) + 3, with a maximum limit of 10 mm.

Installation Process Standards for Steel Structure Projects (Part IV)

3.8.4 Installation Sequence for Portal Frames

Install a single steel column → Adjust the column height → Align the longitudinal and transverse cross-axis positions → Perform initial verticality check → Temporarily secure the column → Make adjustments to correct any deviations → Finalize the installation.
The inclined beams shall be leveled on wooden pads on the ground and assembled using high-strength bolts.
Installation shall commence with the two rigid frames located near the gable end and equipped with inter‑column bracing, followed by the erection of all members within this bay, including purlins, bracings, and corner braces.
Except for the two initial steel frames installed, the bolts connecting the purlins, wall beams, and eave purlins between the remaining steel frames shall be tightened only after alignment.
The tightening of all types of supports shall be adjusted so as not to cause the components to bend.
When installing purlins and wall beams, tie rods shall be installed and tightened, but care must be taken to avoid inducing bending in the members.
If the span is relatively long, two rigid frames may also be installed starting from the center, following the sequence of column → intercolumnar beam → roof purlin → bracing → purlin. Once a stable spatial system has been established, extension can proceed toward both ends.
During construction, in accordance with structural stability requirements and to prevent overturning due to strong winds, guy wires may be installed as needed.
4 Quality Standards

4.1 Key Control Items

4.1.1 All measuring instruments used during installation shall be inspected and verified as compliant by the metrology department before they may be put into service.
4.1.2 Measuring instruments used in the fabrication, installation, and acceptance of steel structures, as well as in civil engineering construction, shall be calibrated to the same standard and maintained at the same accuracy class.
4.1.3 The positioning axes, foundation axes and elevations of the building, as well as the specifications and tightening of anchor bolts, shall comply with the design requirements.
4.1.4 When the top surface of the foundation is used directly as the column bearing surface, or when embedded steel plates or bearings are employed as the bearing surface, the allowable deviations between the bearing surface and the locations of anchor bolts shall comply with the requirements specified in Table 2.

Table 2 Permissible Deviations (mm) for Bearing Surfaces and Anchor Bolt (Anchor Stud) Positions

4.1.5 When using grouting bearing plates, their permissible deviations shall comply with the requirements specified in Table 3.

Table 3 Permissible Deviations for Bedding Plates (mm)

4.1.6 When a cup‑base foundation is used, the permissible deviations in the dimensions of the cup opening shall comply with the requirements specified in Table 4.

Table 4 Permissible Deviations for Cup Rim Dimensions (mm)

4.1.7 During the installation of multi‑storey and high‑rise steel structures, the positioning axes, column axis lines, elevations, as well as the specifications and locations of anchor bolts and their tightening, shall comply with the design requirements; in the absence of specific provisions, compliance shall be in accordance with Table 11.2.1 of the Code for Acceptance of Construction Quality of Steel Structures, GB 50205‑2001.
4.1.8 Deformations and coating damage to steel structures resulting from transportation, stacking, or lifting shall be corrected and repaired.
4.1.9 For design‑required bearing‑type connections, the contact area shall be no less than 70% and tightly fitted, with a maximum edge gap of ≤0.8 mm.
4.1.10 The permissible deviations for the verticality and lateral deflection of steel roof (support) trusses, trusses, beams, and compression members are specified in Table 10.3.3 of the Code.
4.1.11 The allowable deviations for the overall verticality and overall in‑plane curvature of single‑story steel structures are specified in Table 10.3.4 of the Code.
4.1.12 The allowable deviations for the installation of multi-story columns are specified in Table 11.3.2 of the Code.
4.1.13 The allowable deviations for overall verticality and overall planar curvature of multi‑story and high‑rise steel structures are specified in Table 11.3.5 of the Code.
4.1.14 For multi-layered plate assemblies where high-strength bolts are connected to ordinary bolts, a hole‑gauge shall be used for inspection, and the following requirements shall be met:

When using a test probe with a diameter 1.0 mm smaller than the nominal aperture diameter, the pass rate shall be ≥85%.
When using a plug gauge with a diameter 0.3 mm larger than the bolt’s nominal diameter, the pass rate shall be 100%.
4.2 General Items

4.2.1 Permissible deviations for pre-assembly are specified in Appendix D, Table D of the Code for Acceptance of Construction Quality of Steel Structures, GB 50205-2001.
4.2.2 The permissible dimensional deviations for anchor bolts are given in Table 5.

Table 5 Permissible Deviations in Dimensions of Anchor Bolts (Anchor Studs) (mm)

4.2.3 The centerlines and elevation datum marks of steel columns and other major structural members shall be complete.
4.2.4 When steel trusses (or beams) are installed on concrete columns, the deviation of the support center from the reference axis shall not exceed 10 mm; when large‑size concrete roof panels are used, the spacing deviation of the steel trusses (or beams) shall not exceed 10 mm.
4.2.5 The allowable deviations for steel column installation are specified in Appendix Table E.0.1 of the Code.
4.2.6 The permissible installation deviations for steel crane girders or similar members that directly withstand dynamic loads are specified in Appendix Table E.0.2 of the Code.
4.2.7 The allowable deviations for the installation of secondary components such as purlins and wall frames are specified in Table 6.

Table 6: Permissible Deviations (mm) for Installation of Secondary Components such as Purlins and Wall Frames

Note: H — height of the wall‑frame column; h — height of the wind‑resisting truss; L — length of the purlin or wall beam.

4.2.8 The installation of steel platforms, steel ladders, and guardrails shall comply with the provisions of the current national standards: “Fixed Steel Vertical Ladders” GB 4053.1, “Fixed Steel Inclined Ladders” GB 4053.2, “Fixed Guardrails” GB 4053.3, and “Fixed Steel Platforms” GB 4053.4. Permissible deviations are specified in Table 7.

Table 7 Permissible Deviations (mm) for Installation of Steel Platforms, Steel Stairs, and Guardrails

4.2.9 The allowable deviations for the root gap of field welds are specified in Table 8.

Table 8 Permissible Deviations in Alignment Gaps for Field Welds (mm)

4.2.10 The surface of steel structures shall be kept clean, and the primary surfaces shall be free of defects such as scars, dirt, and sand.
4.2.11 The allowable deviations for the installation of multi‑story and high‑rise steel structures are specified in Appendix Table E.0.5 of the Code.
4.2.12 The allowable deviation in the total height of multi‑storey and high‑rise main structures is specified in Appendix Table E.0.6 of the Code.

5 Finished Product Protection

5.1 When steel structural components are stacked on site, the ground shall be firm and well-drained; the components must be elevated by 200 mm and shall not be placed directly on the ground.
5.2 During transportation, loading/unloading, and lifting operations, steel structures shall be provided with reliable reinforcement and protective measures to prevent deformation.

6 Quality Issues to Be Noted

6.1 For the installation of single-story steel structures, it is recommended to proceed in the sequence of vertical members first, followed by planar members, in order to control longitudinal cumulative errors and ensure construction quality.
6.2 During construction, wind-resistant measures such as guy wires shall be implemented in a timely manner in accordance with the structural spatial stability to prevent the rigid frame from overturning.