A steel structure awning installation process for railway station buildings

Abstract

The present invention belongs to the technical field of railway station canopies, and specifically relates to an installation process for a steel structure canopy of a railway station. The installation process for the steel structure canopy of the railway station includes the following steps: S1: Installation of steel columns; S2: Installation of steel beams: When hoisting the steel beams, trial hoisting is required and the hoisting point positions need to be adjusted in a timely manner. During the trial hoisting, the crane hoists slowly to ensure that the forces on each hoisting point position are uniform and the steel beams do not deform. After meeting the requirements, the beams are hoisted and rotated to the designed position; When hoisting the steel beams, the steel columns also need to be rechecked. Generally, a hoist is used to pull a wire rope cable for inspection at this time, and the cable can be released only after the girder is installed; S3: Welding of the steel structure; S4: Painting of the topcoat of the steel structure. The construction process is efficient, enabling the construction to proceed effectively, and the details are processed precisely to ensure the overall structural stability in the later stage.

Description

Technical Field

[0001] The present invention relates to the technical field of railway station canopies, and specifically to an installation process for a steel structure canopy of a railway station building. Background Art

[0002] A railway station building is a large shelter for railway trains to park, and a canopy is laid on the top of the station building to prevent rainwater from entering.

[0003] The canopy of a railway station building is usually fixed on a concrete pedestal on the ground by a steel structure, and a waterproof shed is arranged on the upper steel structure. There are problems with the existing installation process of the canopy, resulting in low overall installation efficiency, and the connection strength is affected due to problems before and after the process. Summary of the Invention

[0004] The purpose of the present invention is to provide an installation process for a steel structure canopy of a railway station building to solve the problems raised in the above background art.

[0005] To achieve the above purpose, the present invention provides the following technical solution: An installation process for a steel structure canopy of a railway station building, the installation process for the steel structure canopy of the railway station building includes the following steps:

[0006] S1: Installation of steel columns:

[0007] Installation of guy ropes: Before hoisting, guy ropes are installed in the upper and middle parts of the steel column, and orientation ropes are installed in the lower part;

[0008] Trial hoisting: When hoisting the steel column, the crane operator should pay close attention to mutual cooperation. The tension of the sling should be ensured to be consistent, and a special person should be arranged to command and maintain concentration. Before formal installation, trial hoisting is carried out first. The steel column is lifted 200 - 220 mm off the ground to check the tension of the sling;

[0009] Hoisting: After the trial hoisting inspection is completed, before hoisting the steel column, one end of the upper guy rope is first tied to the column body of the steel column. The steel column is lifted up to 280 - 320 mm above the reinforced concrete foundation, and the steel column is slowly lowered. The hoisting personnel operate the orientation rope above to make the embedded bolts of the reinforced concrete foundation pass through the bottom plate of the steel column. During the operation, it is strictly prohibited to collide the steel column with the foundation. After the steel column is in place, the installation personnel follow up the operation, and the steel column and the embedded bolts are tightened with nuts for temporary fixation;

[0010] Pull guy ropes: At this time, the height of the steel column meets the requirements. At least three more guy ropes are installed on the steel column with a manual hoist. The guy ropes are tightened with a manual hoist, and the guy ropes are adjusted to make the steel column vertical and make the center line of the steel column coincide with the positioning axis placed on the reinforced concrete foundation to complete the alignment of the steel column. After the guy ropes are firmly fixed, the crane can release the hook to complete the hoisting. The remaining steel columns are installed in the same way;

[0011] S2: Installation of steel beams:

[0012] When hoisting the steel beam, trial hoisting shall be carried out and the position of the lifting point shall be adjusted in time. During the trial hoisting, the crane shall lift slowly to ensure that the forces on each lifting point are evenly distributed and the steel beam remains undeformed. After meeting the requirements, the beam shall be hoisted and rotated to the designed position.

[0013] When hoisting the steel beam, the steel column shall also be rechecked. At this time, a hoist is used to pull the wire rope cable for inspection, and the cable can be released after the girder is installed.

[0014] S3: Steel structure welding:

[0015] Treatment of the bottom layer of the weld bead: The bottom layer of the weld bead shall be cleaned thoroughly, and the groove shall be inspected according to the process requirements. Steel backing plates or ceramic backing plates shall be used at the bottom of the weld. The groove parts of the local weld bead shall be repaired on site until the requirements are met before welding. Before formal welding, the electrodes, welding wires, and weld beads shall be baked to keep them dry, and moisture shall be strictly removed.

[0016] Preheating before welding and interpass temperature: Preheating shall be carried out before welding. The preheating range is 100 - 150 mm outside the weld area. Each welding joint shall be welded in one go during welding.

[0017] Post-weld heat treatment and heat preservation: Post-weld heat treatment shall be carried out immediately after welding. Far-infrared heaters shall be used for heating, which are arranged within a range of 100 mm on each side of the weld, and asbestos cloth shall be wrapped outside for heat preservation. The post-weld heat treatment temperature is 200 - 250 °C. The heat preservation time at this temperature depends on the thickness of the component, which is 0.5 h for every 25 mm of plate thickness, and not less than 1 h. Then the weld shall be cooled to normal temperature.

[0018] Adjusting the position deviation value according to the welding shrinkage: Considering the weld shrinkage after the welding of the steel column and steel beam, a pre-deviation value shall be obtained during the installation and alignment of the component according to the shrinkage value of the weld and the total shrinkage value of the coaxial welds, so that the position of the component returns to the predetermined position after welding. Special attention shall be paid to reducing the cumulative error caused by weld shrinkage.

[0019] Symmetrical welding: As much as possible, symmetrical welds shall be adopted for the steel structure. Two welders with basically the same welding speed shall start welding simultaneously from two symmetrical surfaces until the weld is completed, reducing the deformation of the welded structure caused by asymmetrical welding.

[0020] Eliminating welding residual stress: On the steel structure installation site, the welding residual stress at the joint parts is mainly reduced by reasonably arranging the welding sequence to reduce the restraint degree of the welding joint, post-weld heating, and ultrasonic impact.

[0021] Weld repair: The quality requirements for repaired welds are the same as those for the original welds. The minimum length of the repaired weld is greater than 50 mm. The repaired welding area should be welded continuously in one pass. Before re-welding, magnetic particle or penetrant testing should be used to detect and ensure that there are no cracks before continuing the repair welding. The number of repairs to the same weld area should not exceed two times. For repairs exceeding two times, corresponding repair processes should be developed after identifying the reasons. The repair process must be agreed upon by a welding professional engineer and approved by a supervision engineer before implementation.

[0022] Post-weld cleaning: After welding is completed, the starting plate and ending plate should be cut off using oxyacetylene flame and the weld edges should be ground smooth. On important parts, the welder's number should be stamped with a steel stamp. The welds should be inspected for no undercut, porosity, cracks, weld beads, and geometric dimension deficiencies on the weld surface.

[0023] S4: Painting of the topcoat for steel structures:

[0024] Substrate treatment: Before painting the topcoat of the steel structure, surface dirt should be removed. For rust and aging products generated during storage, welding parts during transportation and assembly, and damaged parts and defects of shop primer during heat treatment, thorough rust removal and repair should be carried out.

[0025] Diluent or cleaning agent should be used to remove grease, lubricating oil, solvents, welding slag, residual welding spatter, and damaged paint coatings at welding or flame straightening areas, and then dried with compressed air.

[0026] Powered grinding wheels or elastic grinding wheel discs should be used to remove welding slag and welding oxide scale.

[0027] After thorough repair according to the above process and steps, the spraying of the second topcoat should be carried out.

[0028] Painting construction

[0029] The anti-corrosion paint for steel structures should provide inspection reports conforming to national standards when leaving the factory, and be accompanied by the variety name, model, technical performance, manufacturing batch number, storage date, instruction manual, and product certificate.

[0030] During construction, various measuring instruments, mixing buckets, and stirrers should be prepared and formulated separately according to the usage methods in the instructions of different materials, and stirred thoroughly.

[0031] Two-component anti-corrosion paint should be formulated strictly according to the ratio, and can be used only after being matured after stirring.

[0032] The topcoat construction should be carried out by spraying.

[0033] Furthermore, in S1, during the trial hoisting process, while checking the tension of the sling, the rationality of the lifting point setting and the stability during component hoisting should be verified.

[0034] Further, in S1, when processing the steel column, the top surface of the steel column is used as the reference plane to determine the length of the steel column body and the positions of other components. Before installation, a mark is made by descending 300 mm from the top surface of the steel column as the reference plane. The mark serves as an aid for steel column alignment, and the elevation is adjusted using the anchor nuts.

[0035] Further, in S1, before hoisting the steel column, center line marks are made on the side of the steel column base plate and the embedded plate respectively. When hoisting the steel column, without unhooking the crane, the center line mark on the steel column base plate can be made to coincide with the mark on the column foundation.

[0036] Further, in S1, the steel column is aligned using a theodolite. The perpendicularity is observed in the x-axis and y-axis directions. During construction, a total station is used to check the perpendicularity. First, align with the vertical flange plate or the center line at the bottom of the steel column, and then gradually look up to the top of the steel column. If the center line deviates from the line of sight, it indicates that the column is not perpendicular. The guy wire can be commanded to be adjusted until the requirements are met. After the temporary fixation of the steel column is completed, the bottom of the steel column is padded solid with shims. When hoisting the beam or installing vertical components, the steel column must also be rechecked and aligned. At the same time, the perpendicularity of the steel column is corrected by means of a plumb line in two perpendicular directions.

[0037] Compared with the prior art, the beneficial effects of the present invention are:

[0038] The construction process is efficient, enabling the construction to proceed effectively, and the details are precisely processed, ensuring the overall structural stability in the later stage. Specific embodiments

[0039] The technical solutions in the embodiments of the present invention are clearly and completely described below. Apparently, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0040] Embodiment:

[0041] The present invention provides a technical solution: an installation process for a steel structure awning of a railway station building, characterized in that the installation process for the steel structure awning of the railway station building includes the following steps:

[0042] S1: Installation of steel columns:

[0043] Install guy wires: Before hoisting, upper guy wires are installed in the upper and middle parts of the steel column, and orientation ropes are installed in the lower part;

[0044] When processing the steel column, the top surface of the steel column is used as the reference plane to determine the length of the steel column body and the positions of other components. Before installation, a mark is made by descending 300 mm from the top surface of the steel column as the reference plane. The mark serves as an aid for steel column alignment, and the elevation is adjusted using the anchor nuts;

[0045] Before hoisting the steel column, make center line marks on the side of the steel column base plate and the embedded plate respectively. When hoisting the steel column, without unhooking the crane, just align the center line mark on the steel column base plate with the mark on the column foundation;

[0046] Trial hoisting: When hoisting the steel column, the crane operators should pay close attention to cooperate with each other. The tension of the slings should be ensured to be consistent, and a special person should be assigned to command and keep concentrated. Before the formal installation, conduct a trial hoisting first. Lift the steel column 200 - 220 mm above the ground and check the tension of the slings. During the trial hoisting process, while checking the tension of the slings, verify the rationality of the sling point setting and the stability of the component during hoisting;

[0047] Hoisting: After the trial hoisting inspection is completed, before hoisting the steel column, tie one end of the upper guy rope to the steel column body first. Lift the steel column up to 280 - 320 mm above the reinforced concrete foundation, and then let the steel column descend slowly. The hoisting personnel operate the upper orientation rope to make the embedded bolts of the reinforced concrete foundation pass through the base plate of the steel column. During the operation, strictly prevent the steel column from colliding with the foundation. After the steel column is in place, the installation operators follow up and operate to tighten the steel column and the embedded bolts with nuts for temporary fixation;

[0048] Pull the guy ropes: At this time, the height of the steel column meets the requirements. Install at least three directions of guy ropes on the steel column with a manual hoist. Tighten the guy ropes with a manual hoist, adjust the guy ropes to make the steel column vertical, and make the center line of the steel column coincide with the positioning axis placed on the reinforced concrete foundation to complete the alignment of the steel column. Only after the guy ropes are fixed firmly can the crane unhook to complete the hoisting. Install the remaining steel columns in the same way;

[0049] The steel column alignment is corrected with a theodolite. Observe the perpendicularity in the x-axis and y-axis directions. During construction, use a total station to check the perpendicularity. First, align with the vertical flange plate or the center line at the bottom of the steel column, and then gradually look up to the top of the steel column. If the center line deviates from the line of sight, it means the column is not vertical, and the pulling rope can be commanded to be adjusted until it meets the requirements. After the temporary fixation of the steel column is completed, the bottom of the steel column is padded firmly with shims. When hoisting the beam or installing vertical components, the steel column must also be rechecked and corrected, and at the same time, the perpendicularity of the steel column is corrected by means of a plumb line in two perpendicular directions.

[0050] S2: Installation of steel beam:

[0051] When hoisting the steel beam, it is necessary to conduct a trial hoisting and adjust the sling point position in time. During the trial hoisting, the crane hoists slowly to ensure that the forces at each sling point position are uniform and the steel beam does not deform. After meeting the requirements, hoist and rotate it to the design position;

[0052] When hoisting the steel beam, the steel column must also be rechecked. At this time, use a hoist to pull a steel wire rope cable for inspection, and the cable can be released only after the girder is installed;

[0053] The hoisting of the main beam should maintain a stable center of gravity. When installing and aligning the main beam between columns, the columns should be propped apart. Measurement should be carried out for tracking and correction, leaving a deviation value, and allowing for shrinkage allowance for joint welding. The welding of column-to-column joints and beam-to-column joints should be coordinated. First, weld the top beam of the column layer by layer, and then weld the joints of each layer of columns and beams from bottom to top. The difference in the levelness at both ends of the same beam should be controlled within (L / 1000) + 3; the maximum should not exceed 10. For the correction of beam verticality: Hang a plumb bob from the upper flange of the beam and measure the horizontal distances from the string to the upper and lower parts of the beam web. According to the inclination of the beam (a ≠ a'), adjust the wedge iron again to make a = a', then it will be vertical. The longitudinal and transverse axes and verticality can be adjusted simultaneously.

[0054] S3: Steel structure welding:

[0055] The on-site welding of this project mainly focuses on the butt welding of steel columns and the transverse butt welding of the flange of steel beams. This project is strictly welded according to the welding process parameters and operation sequence of the "Welding Process Qualification Test";

[0056] Welding material requirements:

[0057] Select the brand of welding materials according to the base metal of the steel structure. The welding material selection table is as follows:

[0058]

[0059] Welding requirements:

[0060] Weather conditions: When the gas shielded welding wind speed exceeds 2 m / s and the manual arc welding wind speed exceeds 8 m / s, good wind protection measures should be taken to prevent pores from forming in the weld. Stop construction in case of rain or snow. If construction needs to be rushed due to progress requirements, except for local heating and wind protection, the weld must be constructed after taking effective rain and snow prevention measures (such as setting up a protective shed).

[0061] Weld bead bottom treatment: The bottom of the weld bead should be cleaned thoroughly, and the groove should be inspected according to the process requirements. Steel backing plates or ceramic backing plates should be used at the bottom of the weld. Repair the groove of the local weld bead on-site until it meets the requirements before welding. Before formal welding, the electrodes, welding wires, and weld beads should be baked to keep them dry, and moisture should be strictly removed;

[0062] Preheating before welding and interlayer temperature: Preheat before welding, and the preheating range is 100 - 150 mm outside the weld area. Each welding joint should be welded in one go during welding; Before welding, pay attention to collecting meteorological forecast information. If it is expected that bad weather is coming and there is no definite assurance to resist it, welding should be abandoned. If the weld has started welding, before the bad weather comes, at least 1 / 3 of the plate thickness should be welded before stopping; and strict post-weld heat treatment should be carried out, and the interlayer temperature should be recorded.

[0063] Post-weld heat treatment and heat preservation: Post-weld heat treatment shall be carried out immediately after welding. Far-infrared heaters shall be used for heating, which are arranged within a range of 100 mm on both sides of the weld seam, and asbestos cloth shall be wrapped outside for heat preservation. The post-weld heat treatment temperature is 200 - 250 °C. The heat preservation time at this temperature shall be determined according to the thickness of the component, which is 0.5 h for every 25 mm of plate thickness and not less than 1 h. Then, the weld seam shall be cooled to normal temperature;

[0064] Adjust the position deviation value according to the welding shrinkage: Considering the weld seam shrinkage after the welding of steel columns and steel beams, a pre-deviation value shall be obtained during the installation and alignment of the components according to the shrinkage value of the weld seam and the total shrinkage value of the coaxial weld seams, so that the position of the component returns to the predetermined position after welding is completed. Special attention shall be paid to reducing the cumulative error caused by weld seam shrinkage;

[0065] Symmetrical welding: As much as possible, symmetrical weld seams shall be adopted for the steel structure. Two welders with basically the same welding speed shall start welding simultaneously from two symmetrical surfaces until the weld seam is welded completely, so as to reduce the deformation of the welded structure caused by asymmetrical welding;

[0066] Elimination of welding residual stress: At the steel structure installation site, the welding residual stress at the joint parts shall be reduced mainly by reasonably arranging the welding sequence to reduce the restraint degree of the welding joint, post-weld heating, and ultrasonic peening;

[0067] Weld repair: The quality requirements for the repaired weld seam shall be the same as those for the original weld seam, and the minimum length of the repaired weld seam shall be greater than 50 mm; The repaired welding part shall be welded continuously at one time. If the welding needs to be interrupted due to reasons, post-weld heat treatment and heat preservation measures shall be taken to prevent cracks from occurring; Before welding again, magnetic particle or penetrant testing shall be used to detect, and it can continue to be repaired after confirming that there are no cracks. The number of repairs for the same weld seam part shall not exceed two times. For repairs more than two times, corresponding repair processes shall be formulated after finding out the reasons, and the repair processes must be agreed by the welding professional engineer and approved by the supervision engineer before implementation;

[0068] Post-weld cleaning: After welding is completed, the starting plate and ending plate shall be cut by oxyacetylene flame and the weld seam edge shall be polished smoothly. The welder's number shall be stamped with a steel seal at important parts. It shall be checked that the weld seam shall not have defects such as undercut, porosity, crack, and weld bead, and there shall be no phenomenon of insufficient geometric dimensions on the weld seam surface;

[0069] During the welding construction process, records must be made well.

[0070] The surface defects of the weld seam shall be inspected 100%, and the inspection standards shall be carried out in accordance with the current national relevant specifications.

[0071] Inspection of internal defects of weld seam: For the first and second grade weld seams requiring full penetration, ultrasonic flaw detection shall be used for internal defect inspection. If ultrasonic flaw detection cannot judge the defects, radiographic inspection shall be used. The calculation method of the flaw detection ratio shall be in accordance with Table 5.2.4 in GB50205 - 2020.

[0072] The rest shall be carried out in accordance with the Code for Construction and Acceptance of Steel Structure Engineering (GB50205-2020) and the Code for Steel Structure Welding (GB50661-2011).

[0073] S4: Painting of the topcoat for steel structure:

[0074] Control of construction climate conditions

[0075] The main factors that must be noted when applying paint are the surface condition of the steel, the steel temperature, and the atmospheric environment during painting. Generally, painting construction work should be carried out under climate conditions where the temperature is above 5°C and the relative humidity is below 85%. When the surface is affected by harsh climates such as strong winds, rain, fog, or ice and snow, painting construction cannot be carried out.

[0076] Measure the steel temperature with a thermometer, measure the relative humidity with a hygrometer, and then calculate the dew point. When the steel temperature is 3°C above the dew point, painting cannot be carried out due to surface condensation of water, and construction must be carried out when it is 3°C above the dew point.

[0077] Under low-temperature conditions where the temperature is below 5°C, the curing speed of the anti-corrosion paint slows down or even stops curing. Depending on the surface drying speed of the coating, methods such as increasing the workpiece temperature, reducing the air humidity, and strengthening air circulation can be adopted to solve the problem.

[0078] When constructing under harsh conditions where the temperature is above 30°C, since the solvent volatilizes very quickly, it is necessary to dilute with a thinner accounting for about 5% of the paint's own weight before construction can be carried out.

[0079] Substrate treatment:

[0080] Before applying the topcoat for steel structure, remove the surface dirt. Thoroughly remove rust and aging substances generated during the storage period, welding parts during transportation and assembly, and damaged parts and defects of the shop primer during heat treatment;

[0081] Use a thinner or cleaning agent to remove grease, lubricating oil, solvents, welding slag, residual welding spatter, and damaged paint coatings at the welding or thermal straightening areas, and blow dry with compressed air;

[0082] Remove welding slag and welding oxide scale with a power grinding wheel or elastic grinding wheel disc;

[0083] To protect the steel surface, once the steel surface is cleaned, it must be wiped clean. After inspection and complete compliance with the construction requirements, the first anti-rust primer can be immediately applied.

[0084] After thoroughly repairing according to the above process and steps, carry out the spraying work of the second topcoat;

[0085] The above is a concealed project. A concealed project acceptance form must be filled out and submitted to the supervisor or owner for acceptance before topcoat construction can be carried out.

[0086] Painting construction

[0087] When steel structure anti-corrosion paint leaves the factory, an inspection report that complies with national standards shall be provided, along with the product name, model, technical performance, manufacturing batch number, storage date, instruction manual and product certificate;

[0088] Various measuring instruments, batching barrels and mixers should be prepared for construction, and the materials should be prepared according to the instructions in the material manual and fully mixed;

[0089] Two-component anti-corrosion paints should be prepared strictly according to the proportions and can only be used after being stirred and matured;

[0090] The topcoat application is carried out by spraying;

[0091] Construction workers should undergo professional training and practical construction training, and be certified before they can take up their posts.

[0092] The spraying of anti-corrosion topcoat should be carried out in the order of components. During construction, attention should be paid to spraying layer by layer to prevent missing sprays and ensure that each process is strictly controlled.

[0093] The coating after spraying should have a smooth surface, clear contours, uniform color, no delamination, no hollowing, no sagging, and no pinholes, and the film thickness should meet the requirements specified in the technical indicators.

[0094] The film thickness is the key to the best performance of the anti-corrosion coating. Sufficient film thickness is extremely important. Therefore, the thickness must be strictly controlled. During construction, the coating should be applied according to the usage amount. The wet film thickness gauge should be used frequently to measure the wet film thickness in order to control the dry film thickness and ensure uniform thickness.

[0095] The above shows and describes the basic principles and main features of the present invention and the advantages of the present invention. For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and the present invention can be implemented in other specific forms without departing from the spirit or basic characteristics of the present invention; therefore, no matter from which point of view, the embodiments should be regarded as exemplary and non-restrictive. The scope of the present invention is limited by the attached claims rather than the above description, and it is intended to include all changes within the meaning and scope of the equivalent elements of the claims in the present invention.

[0096] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A steel structure awning installation process for railway station buildings, characterized in that, The installation process of the steel structure awning of the railway station building includes the following steps: S1: Installation of steel columns: Installation of guy ropes: Before hoisting, upper guy ropes are installed in the middle and upper parts of the steel column, and lower directional ropes are installed at the lower part; Trial hoisting: When hoisting the steel column, the crane operators should pay close attention to cooperation. The tightness of the sling should be ensured to be consistent, and a special person should be assigned to command and maintain concentration. Before formal installation, conduct a trial hoisting. Lift the steel column 200 - 220 mm off the ground and check the tightness of the sling; Hoisting: After the trial hoisting inspection is completed, before hoisting the steel column, tie one end of the upper guy rope to the column body of the steel column first. Lift the steel column up to 280 - 320 mm above the reinforced concrete foundation, and let the steel column slowly descend. The hoisting personnel operate the upper directional rope to make the embedded bolts of the reinforced concrete foundation pass through the bottom plate of the steel column. During the operation, prevent the steel column from colliding with the foundation. After the steel column is in place, the installation operators follow up and operate to tighten the steel column and the embedded bolts with nuts for temporary fixation; Tighten the guy ropes: At this time, the height of the steel column meets the requirements. Use a manual hoist to install at least three more guy ropes on the steel column. Tighten the guy ropes with a manual hoist, adjust the guy ropes to make the steel column vertical, and make the center line of the steel column coincide with the positioning axis placed on the reinforced concrete foundation to complete the alignment of the steel column. After the guy ropes are firmly fixed, the crane can release the hook to complete the hoisting. Install the remaining steel columns in the same way; S2: Installation of steel beams: When hoisting the steel beam, it is necessary to conduct a trial hoisting and adjust the position of the lifting point in a timely manner. During the trial hoisting, the crane slowly hoists, ensuring that the forces at each lifting point are evenly distributed and the steel beam does not deform. After meeting the requirements, hoist and rotate it to the designed position; When hoisting the steel beam, it is also necessary to recheck the steel column. At this time, use a hoist to pull the steel wire rope cable for inspection, and the cable can be released after the girder is installed; S3: Welding of steel structure: Treatment of the bottom layer of the weld: The bottom layer of the weld should be cleaned, and the groove should be inspected according to the process requirements. Steel backing plates or ceramic backing plates are used at the bottom of the weld. Repair the local weld groove on site until it meets the requirements before welding. Before formal welding, the electrodes, welding wires, and welds should be baked to keep them dry, and moisture should be strictly removed; Preheating before welding and interpass temperature: Preheat before welding. The preheating range is 100 - 150 mm outside the weld area. Each welding joint should be welded in one go during welding; Post-weld heat treatment and heat preservation: Immediately conduct post-weld heat treatment after welding. Use a far-infrared heater for heating, which is arranged within a range of 100 mm on each side of the weld, and wrap it with asbestos cloth for heat preservation. The post-weld heat treatment temperature is 200 - 250 °C. The heat preservation time at this temperature depends on the thickness of the component, which is 0.5 h for every 25 mm of plate thickness, and not less than 1 h, and then let the weld cool down to normal temperature; Adjust the position deviation value according to the welding shrinkage: Considering the weld shrinkage after welding of the steel column and steel beam, based on the shrinkage value of the weld and the total shrinkage value of the coaxial welds, obtain a pre-deviation value during the installation and alignment of the components, so that the position of the component returns to the predetermined position after welding. Pay special attention to reducing the cumulative error caused by weld shrinkage; Symmetrical welding: Steel structures should adopt symmetrical welds as much as possible, and two welders with basically the same welding speed should start welding from two symmetrical surfaces at the same time until the weld is completed, so as to reduce the deformation of the welded structure caused by asymmetrical welding; Elimination of welding residual stress: The main measures taken at the steel structure installation site are to arrange the welding sequence reasonably to reduce the constraint of the welding nodes, post-weld heating, and ultrasonic impact to reduce the welding residual stress at the node parts; Weld repair: The quality requirements of the repaired weld are the same as those of the original weld, and the minimum length of the repaired weld is greater than 50mm; the repaired welded part should be welded continuously at one time; before welding again, magnetic powder or penetration method detection should be applied to confirm that no cracks have occurred before continuing to weld. The number of repairs on the same part of the weld should not exceed two times. If the repair exceeds two times, the corresponding repair process should be formulated after the cause is found out. The repair process must be agreed by the welding professional engineer and approved by the supervision engineer before it can be implemented; Post-weld cleaning: After welding, the arc starter plate and arc extinguisher plate should be cut with oxyacetylene flame and the weld edge should be polished and smoothed. The welder's number should be stamped on important parts. Check that the weld should not have undercuts, pores, cracks, weld nodules, and insufficient weld surface geometry. S4: Steel structure topcoat painting: Base treatment: Before applying the steel structure topcoat, remove the dirt on the surface, thoroughly remove rust and aging produced during storage, welding parts during transportation and assembly, and damaged parts and defects of the workshop primer produced during heat treatment; Use thinner or cleaning agent to remove grease, lubricating oil, solvent, welding slag, welding spatter residue, and damaged paint coating at welding or pyrotechnic correction, and blow dry with compressed air; Use a powered grinding wheel or elastic grinding wheel to remove welding slag and welding oxide scale; After thorough repair according to the above process and steps, spray the second coat of topcoat; Painting construction: When steel structure anti-corrosion paint leaves the factory, an inspection report that complies with national standards shall be provided, along with the product name, model, technical performance, manufacturing batch number, storage date, instruction manual and product certificate; Various measuring instruments, batching barrels and mixers should be prepared for construction. Different materials should be prepared according to the instructions for use in the instructions and mixed thoroughly. Two-component anti-corrosion paints should be prepared strictly according to the proportions and can only be used after being stirred and matured; The topcoat is applied by spraying.

2. The installation process of a steel structure awning for a railway station building according to claim 1, characterized in that: In S1, the trial lifting process checks the tension of the slings and verifies the rationality of the lifting point settings, as well as the stability of the components during lifting.

3. The installation process of a steel structure awning for a railway station building according to claim 1, characterized in that: In S1, when processing the steel column, the top surface of the steel column is used as the reference plane to determine the length of the steel column body and the position of other components. Before installation, a mark is made 300mm below the top surface of the steel column as the reference plane. The mark serves as an aid for steel column calibration, and the elevation is adjusted using the anchor nuts.

4. The installation process of a steel structure awning for a railway station building according to claim 1, characterized in that: In S1, before the steel column is hoisted, the center line marks are made on the side of the steel column bottom plate and the embedded plate respectively. When the steel column is hoisted, the center line mark on the steel column bottom plate can be overlapped with the mark on the column base without unhooking the crane.

5. The installation process of a steel structure awning for a railway station building according to claim 1, characterized in that: In S1, the steel column is corrected with a theodolite. The verticality is observed in the x-axis and y-axis directions. During construction, a total station is used to check the verticality. First, align with the vertical flange plate or the center line at the bottom of the steel column, and then gradually look up to the top of the steel column. If the center line deviates from the line of sight, it means the column is not vertical. The adjustment of the guy rope can be commanded until the requirements are met. After the temporary fixation of the steel column is completed, the bottom of the steel column is padded firmly with shims. When hoisting the beam or installing vertical components, the steel column must also be rechecked and corrected. At the same time, the verticality of the steel column is corrected by means of a plumb line in two perpendicular directions.

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