CN114370188A - Construction method for public pipe gallery of industrial plant area in severe cold region - Google Patents

Abstract

The invention discloses a construction method of a common pipe gallery in an industrial plant area in a severe cold region, which comprises the steps of preparing before S1 construction, excavating S2 foundation earthwork, binding S3 foundation steel bars and pouring concrete, embedding anchor bolts, backfilling and checking S4 foundation earthwork, installing S5 pipe gallery, secondarily grouting S6 foundation, coating S7 pipe gallery frames and the like, wherein a large amount of high-altitude operation is changed into ground, so that the danger of the high-altitude operation is greatly reduced, and the construction quality is favorably improved; the trouble of setting up and removing a large amount of temporary supports and the trouble of working at high altitude from top to bottom are reduced. Compared with the traditional construction method, the construction method has the advantages of strong pertinence, easy operation and good control, greatly improves the corrosion resistance of the pipe rack in the severe cold area, has obvious advantages on the project progress and cost control, greatly reduces labor cost, material cost and hoisting cost, reduces the construction cost and shortens the construction period.

Description

Construction method for public pipe gallery of industrial plant area in severe cold region

Technical Field

The invention relates to the technical field of construction, in particular to a construction method of a public pipe gallery in an industrial plant area in a severe cold region.

Background

In recent years, along with infrastructure construction along the line and a batch of industrial projects, especially the development of chemical projects at a near-phase stage, the current chemical projects are continuously concentrated to chemical parks, so that the number of the chemical parks is gradually increased, and the park management becomes the main trend of the development of the chemical industry. The chemical industry park plays an important role in promoting the aspects of safe production, energy conservation, emission reduction, circular economy and the like of the chemical industry, the safe and environment-friendly management work of the chemical industry park is more and more emphasized by the society, and as the public pipe gallery has the advantages of large transportation volume, rapidness, economy, safety, reliability, stable operation, less investment, small occupied area, low cost, no limitation by other factors such as climate, ground and the like, the chemical industry park can continuously operate, has no pollution and the like, and is widely applied to the chemical industry park.

And the requirement for the corrosion resistance of the pipe gallery in severe cold areas is higher, and the pipe gallery frame, the connecting bolts and the foundation bolts are generally required to be made of Q235D. At present, a unified standardized construction technical scheme is not provided for the construction in the aspect, in the actual construction process, the pertinence is not strong, the control is not easy, the corrosion resistance of the pipe rack installed in a severe cold area is poor, and the engineering quality cannot be effectively guaranteed; in the traditional construction process, a large amount of temporary supports are erected and removed, so that the operation is complicated, and the working efficiency is low; meanwhile, the high-altitude operation amount is very large, the safety is poor, the stability is not high, and the cost is high.

Disclosure of Invention

The invention aims to: the utility model provides a construction method of a public pipe gallery in industrial plant areas in severe cold areas, which aims to solve the defects.

In order to achieve the above purpose, the invention provides the following technical scheme:

a construction method for a public pipe gallery of an industrial plant area in a severe cold area comprises the following steps:

s1, preparation before construction:

s11, compiling a basic construction scheme and a steel structure installation scheme, and after approval, organizing professional technicians to be familiar with drawings and acceptance criteria, knowing characteristics and key points of the whole construction process, participating in drawing review, compiling construction budget, and providing a labor force plan, a mechanical equipment plan and a construction network progress chart;

s12, checking and accepting the approach materials, arranging the operation environment of the construction site, familiarizing with the steel structure installation process and quality requirements, and performing targeted technical background for constructors; preparing various materials required by construction, supporting a formwork, and reinforcing a used template, a steel pipe and a fastener;

s13, dividing construction areas according to the actual conditions of the project, making a flow process diagram, checking the actual conditions of the site by contrasting the construction diagram, sorting out the parts which cannot be constructed according to the design intention in advance, and negotiating the construction method with the design in advance;

s2, excavating foundation earthwork:

the pipe gallery foundation is an independent foundation, and foundation earth excavation is carried out by adopting a method of combining a backhoe excavator and a dump truck for carrying earth; the earthwork with better soil quality is transported to a specified soil piling position by a dump truck; the foundation pit slope coefficient is 1: 1.2, reserving 300mm of an outer side line of a foundation pit cushion layer as a construction working surface, and manually cleaning a base with 200-300 mm of length during foundation earthwork excavation;

s3, binding and pouring concrete for foundation steel bars and embedding foundation bolts:

s31, blanking is carried out in the steel bar processing shed according to the design requirements of a drawing, steel bars are bound, then the steel bars are transported to a construction operation point for installation, and the semi-finished materials which cannot be prefabricated are transported to the construction operation point for binding;

s32, building a bearing stratum;

s33, filling a layer of plain concrete C20 under the foundation bearing platform, and binding the foundation bearing platform steel bars after the strength is achieved; then pouring concrete C35, after the concrete strength of the bearing platform meets the requirement, supporting a template, fixing foundation bolts at the upper opening of the reinforcement cage, and then pouring concrete C35;

s34, commercial mixing is adopted for the concrete, when the concrete is vibrated, the inserting distance of the vibrating rods is 400mm, the vibrating time is 15-30S, and the pouring interval time of the concrete between the upper layer and the lower layer is not more than the initial setting time of the concrete;

s35, after the strength of the concrete column meets the form removal requirement, removing the form in time and coating epoxy asphalt with the thickness of 300 mu m on the surfaces of the reinforced concrete column and the foundation beam;

s4, backfilling and acceptance of foundation earthwork:

backfilling earthwork, checking the foundation, handling the acceptance of the concealed project and making an acceptance record; selecting soil dug in the foundation pit as the soil quality of the earthwork backfill; the foundation earthwork backfill is artificially compacted and filled in layers, each layer is less than or equal to 300mm, and the compaction coefficient is more than or equal to 94 percent;

s5, mounting pipe gallery

S51, preparation for installation

S511, checking the components transported to the site according to component detail tables before hoisting the steel components, and checking and accepting deformation conditions of the components in the transportation process; for the foundation and the embedded foundation bolts, checking the position of a rechecking axis, height deviation, flatness and elevation, and then popping out a cross center line and guiding and measuring the elevation;

s512, measurement

Basic inspection, paying off and elevation block setting; retesting the control points and axes of civil engineering handover, and correcting in time; measuring and releasing the required control line, and leading out the control line to ensure the visibility; detecting the external dimensions of the steel member according to relevant regulations before installation; the longitudinal and transverse axis measurement determines positioning points according to a total station, and the control points adopt the axis of the theodolite; after a steel ruler, a theodolite and a level are checked, firstly, the positions of a beam and a column are determined according to the positions of a design drawing, then a steel structure mounting position line and an auxiliary line are released, and the steel structure mounting position line and the auxiliary line are marked by bright and firm colors;

s52, mounting the pipe gallery column:

hoisting a steel column by adopting a single machine rotation method, and righting a steel beam, turning over and lifting a plate by adopting a two-point plate lifting method; while hoisting the steel beams, the tie bars between every two steel beams are simultaneously installed after the steel columns and the steel beams are corrected, form a stable system with the rigid frame and sequentially hoist until the hoisting is finished;

s521, hoisting and correcting the steel column:

hoisting the steel column, adopting manual lifting to assist in positioning, and hoisting the component in position by adopting a single-machine rotating method; vertically correcting the column, namely arranging two theodolites on a longitudinal axis and a transverse axis for measurement, and then correcting;

s522, mounting a sizing block:

accurately marking the position of the sizing block according to the position of each central line and the layout schematic diagram of the sizing block; then carrying out installation, slicing and leveling of the sizing blocks, and finally carrying out electric welding to firmly weld each layer of sizing blocks by electric welding before the concrete is poured for the second time;

s523, mounting of the high-strength bolt:

when the high-strength bolts are connected and installed, the number of temporary bolts and punching nails to be penetrated into each node is determined by calculation of loads possibly borne during installation; the torque wrench used for the fastening construction of the high-strength bolt needs to be corrected before use, the torque error is less than or equal to +/-5 percent, and the torque wrench can be used after being qualified; the tightening of the high-strength bolt is divided into initial tightening and final tightening, and the verticality and the levelness between the components are adjusted immediately after the hoisting is finished; all components of the high-strength bolt are connected with the contact surface, after sand blasting treatment, an anti-slip coefficient experiment should be carried out before construction, and after inspection is qualified, high-strength bolt assembly can be carried out;

s524, cleaning and overhauling:

before leaving the field every day, metal garbage such as waste nails, sundries and the like is cleaned to prevent oxidation and rusting, the sundries are completely cleaned after the metal garbage is completely finished, whether the finished place is finished according to requirements is checked, and if the metal garbage is not finished, the metal garbage is immediately repaired;

s53, hoisting and correcting the steel beam:

the steel beam components are transported to the site and are firstly assembled, a two-point turning-over plate lifting method is adopted when the steel beams need to be turned over and lifted, and the plates are temporarily assisted by manpower by using short steel pipes and square timbers; when the steel beam is hoisted, the steel column needs to be rechecked, a calabash steel wire rope cable is generally adopted for inspection, and the cable can be loosened after the girder is installed;

s54, allowable deviation of pipe gallery installation:

the allowable deviation value of the installation of the pipe gallery meets the specified requirement, all the upright columns are inspected, and the diagonal lines of the beam and the vertical face are spot-inspected by 10% according to the type and need to be more than or equal to 3;

s6, foundation secondary grouting:

the center of the steel structure frame is retested for one time before irrigation, and secondary irrigation can be carried out within an adjustable range; the cement used by the secondary poured concrete adopts micro-expansion cement, and an accelerator is not used; the grouting material is fine stone concrete, so that the column bottom plate is completely contacted with the foundation, and the grade of the grouting concrete is higher than that of the column concrete by one grade; the secondary irrigation work is continuously carried out without interruption; after pouring, the mortar splashed to the surfaces of the column bottom plates and the bolts is immediately wiped clean and maintained according to requirements;

s7, coating the pipe rack:

before coating, checking whether the surface treatment of the steel meets the requirement of the rust prevention grade and is not lower than Sa2.5, then checking whether the phenomenon of rust return or recontamination still exists, if not, retreating is needed, and simultaneously spraying primer within 12 hours after rust removal; then, for parts which do not need to be coated and are prohibited to be painted, masking the parts by using a gummed paper tape in advance so as to avoid painting; and finally, coating an anticorrosive layer on the pipe rack constructed in the severe cold area according to the standard requirement, thereby completing the whole process of the construction method of the public pipe rack in the industrial plant area in the severe cold area.

Preferably, in step S32, the pebble layer is used as the bearing layer.

Preferably, in the step S32 of constructing the bearing stratum, if the base design bottom elevation does not reach the bearing stratum, the base design bottom elevation is backfilled with graded broken stones, and the base design bottom elevation is compacted to the design elevation by layering and rolling; wherein the layering thickness is 300mm, the compaction coefficient is 0.97, and the bearing capacity characteristic value is 200 kPa.

Preferably, in step S512, the specific steps of basic checking, paying off, and setting the elevation block are: firstly, the basic re-calibration positioning uses an axis control point and a reference point of a measuring axis; then, processing impurities on the surface of the foundation, and popping longitudinal and transverse axes of the column on the surface of the foundation; and finally, after the elevation blocks are adjusted, pouring concrete in the range of the column bottom according to the elevation, and retesting the axis.

Preferably, in step S521, the steel column is hoisted and corrected, and the detailed steps include:

(1) hoisting the steel column, adopting manual lifting to assist in positioning, and hoisting the component in position by adopting a single-machine rotating method; in order to improve the hoisting efficiency, when the columns are stacked, three points of binding points of the columns, the centers of column bases and the center of a foundation are in a common arc as much as possible;

(2) when in lifting, the bound column is slowly lifted up by the crane for 20cm from the ground and then is temporarily set, the firmness of the sling and the stability of the crane are checked, and meanwhile, a rotary brake is opened; then, placing the steel column down to be 40-100mm away from the installation surface, aligning with the datum line, commanding the crane to descend, and inserting the column into the anchoring bolt for temporary fixation; after the steel column is primarily corrected, the crane is unhooked when the perpendicularity deviation is controlled within 20mm, the perpendicularity of the steel column is checked by a theodolite, the deviation is corrected, and whether the gap between the bottom and the elevation control block is empty or not is observed at any time in the correction process so as to prevent a horizontal elevation error from being caused in the correction process;

(3) vertically correcting the column, namely arranging two theodolites on a longitudinal axis and a transverse axis for measurement, aligning a vertical flange plate or a central line at the bottom of the column, and gradually looking up to the top of the column; if the midline deviates from the sight line, the post is not vertical, the adjusting pull rope or the support can be commanded, and the post can be vertical by a beating method; in practical work, rows of columns are often erected and then corrected; at this time, two theodolites can be respectively arranged on one side of the longitudinal axis and the transverse axis, the distance deviating from the center line is less than or equal to 3m, and when the vertical component is installed, the steel column needs to be rechecked and corrected.

Preferably, in step S522, the mounting, slicing and leveling of the sizing block are performed by the following detailed method: the thickness of the sizing block is subjected to a small amount of slicing on the height difference of each bearing surface according to the installed elevation requirement, the slicing amount is 5mm, then the supporting surface of the sizing block is flatly shoveled, the contact surface reaches more than 70%, four corners are stable, the corresponding elevation is measured by a level gauge, the leveling is performed by using the level of 0.05mm/m, and the basic surface treatment requirement of the lower leveling sizing block penetrating through the bolt is the same as that of the upper leveling sizing block; each group ofWhen the sizing blocks are planed and scraped, the sizing blocks are numbered according to the positions of the sizing blocks so as to avoid misplacement, the joint of each sizing block is ground by a coloring method, and the thickness of the joint is 25 multiplied by 25mm²The contact area reaches more than 75 percent when the contact point is 3-5 points in the range; leveling the arranged sizing block by using a level meter and a ruler.

Preferably, in step S7, the thickness of the corrosion-resistant layer of the pipe rack is greater than or equal to 240um, wherein the thickness of the epoxy zinc-rich primer is greater than or equal to 50um, the thickness of the epoxy zinc-rich intermediate paint is greater than or equal to 140um, and the thickness of the polyurethane finish paint is greater than or equal to 50 um.

The invention has the beneficial effects that:

the invention discloses a construction method of a common pipe gallery in an industrial plant area in a severe cold area, which adopts the steps of preparing before S1 construction, excavating S2 foundation earthwork, binding S3 foundation steel bars and pouring concrete, embedding anchor bolts, backfilling and accepting S4 foundation earthwork, installing S5 pipe gallery, secondarily grouting S6 foundation, coating S7 pipe gallery frames and the like, thereby realizing the high-quality standardized construction method of the common pipe gallery in the industrial plant area in the severe cold area. Compared with the traditional construction method, the construction method has the advantages of strong pertinence, easy operation and good control, and greatly saves construction manpower, machines and auxiliary materials; a large amount of high-altitude operation is carried out on the ground, so that the danger of the high-altitude operation is greatly reduced; because of the construction on the ground, the safety of constructors is increased, which is beneficial to improving the welding quality and is convenient for taking measures for ensuring the quality; the trouble of setting up and removing a large amount of temporary supports and the trouble of working at high altitude from top to bottom are reduced, so that the working efficiency is improved. Meanwhile, the construction method can ensure good engineering quality, particularly, the corrosion resistance of the pipe rack in the severe cold region is greatly improved by adopting the steel Q235D, the advantages of the construction method on engineering progress and cost control are obvious, labor cost, material cost and hoisting cost are greatly reduced, construction cost is reduced, and construction period is shortened.

Drawings

FIG. 1: the construction process flow chart of the invention;

FIG. 2: the column bottom elevation guiding and indicating diagram of the invention;

FIG. 3: the hoisting schematic diagram of the single-machine rotation method is shown;

FIG. 4: the invention discloses a vertical correction schematic diagram of a steel column;

FIG. 5: the invention is a schematic diagram of steel beam correction, column base sizing block installation and high-strength bolt screwing;

FIG. 6: the invention discloses a schematic lifting diagram of a steel beam.

Detailed Description

The present invention is further described with reference to the following examples, which are intended to be illustrative and illustrative only, and various modifications, additions and substitutions for the specific embodiments described herein may be made by those skilled in the art without departing from the spirit of the invention or exceeding the scope of the claims.

As shown in fig. 1, a preparation method of a construction method of a public pipe gallery in an industrial plant area in a severe cold region specifically comprises the following steps:

s1, preparation before construction:

s11, compiling a basic construction scheme and a steel structure installation scheme, and after approval, organizing professional technicians to be familiar with drawings and acceptance criteria, knowing characteristics and key points of the whole construction process, participating in drawing review, compiling construction budget, proposing a labor force plan, a mechanical equipment plan and a construction network progress chart, and rechecking the drawings; defining a construction organization and management personnel, and allocating corresponding labor force and machines;

s12, checking and accepting the approach materials, arranging the operation environment of the construction site, familiarizing with the steel structure installation process and quality requirements, and performing targeted technical background for constructors; preparing various materials required by construction, supporting a formwork, and reinforcing a used template, a steel pipe and a fastener;

s13, dividing construction areas according to the actual conditions of the project, and determining the labor and material consumption according to the construction areas; making a flow process diagram, and particularly detailing the operation position and the operation time of each layer and each flow section of each process; training operating workers according to the requirements of the engineering; operators of special work species must be certified for post work; checking the actual situation of the site by contrasting the construction drawing, sorting out the parts which cannot be constructed according to the design intention in advance, and negotiating the construction method with the design in advance;

s2, excavating foundation earthwork:

the pipe gallery foundation is an independent foundation, and foundation earth excavation is carried out by adopting a method of combining a backhoe excavator and a dump truck for carrying earth; the earthwork with better soil quality is transported to a specified soil piling position by a dump truck; the foundation pit slope coefficient is 1: 1.2, reserving 300mm of an outer side line of a foundation pit cushion layer as a construction working surface, and manually cleaning a base with 200-300 mm of length during foundation earthwork excavation;

s3, binding and pouring concrete for foundation steel bars and embedding foundation bolts:

s31, blanking is carried out in the steel bar processing shed according to drawing design requirements, steel bars are bound, then the steel bars are transported to a construction operation point for installation, the lower semi-finished product materials which cannot be prefabricated are transported to the construction operation point for binding, and the shape and the size of the processed steel bars are according to the design drawing and the construction specification;

s32, generally taking a pebble layer as a bearing stratum, if the base design bottom elevation does not reach the bearing stratum, backfilling with graded broken stones, and carrying out layered rolling compaction to the design elevation; the layering thickness is 300mm, the compaction coefficient is 0.97, and the bearing capacity characteristic value is 200 kPa;

s33, filling a layer of plain concrete C20 under the foundation bearing platform, and binding the foundation bearing platform steel bars after the strength is achieved; then pouring concrete C35, after the concrete strength of the bearing platform meets the requirement, supporting a template, fixing foundation bolts at the upper opening of the reinforcement cage, and then pouring concrete C35;

s34, generally adopting commercial mixing for concrete, wherein when vibrating the concrete, the inserting distance of the vibrating rods is generally about 400mm, the vibrating time is generally 15-30S, and the concrete pouring interval time between the upper layer and the lower layer does not exceed the initial setting time of the concrete; when the upper layer concrete is poured after the lower layer concrete is initially set, the upper layer concrete is treated according to the stipulation of the reserved construction joint;

for foundation bolts and shear key grooves, the rising speed of concrete is well controlled when the concrete is poured, so that the concrete rises uniformly and is prevented from colliding, and displacement or deflection is avoided; for the large-diameter foundation bolt, in the concrete pouring process, a theodolite is used for observing at any time, and the found deviation is corrected in time;

after the concrete is vibrated, a worker screeds the surface of the concrete to make the surface of the concrete meet the design requirement; curing is started within 12 hours after the concrete is tamped, and the concrete curing time meets the design and specification requirements;

s35, after the strength of the concrete column meets the form removal requirement, removing the form in time and coating epoxy asphalt with the thickness of 300 mu m on the surfaces of the reinforced concrete column and the foundation beam;

s4, backfilling and acceptance of foundation earthwork:

backfilling earthwork, checking the foundation, handling the acceptance of the concealed project and making an acceptance record; the soil quality of the earthwork backfill is the soil dug out from the foundation pit, but organic impurities cannot be contained, and the particle size and the water content of the earthwork backfill meet the requirements before use; the foundation earthwork backfill is artificially compacted and filled in layers, each layer is less than or equal to 300mm, the compaction coefficient is more than or equal to 94 percent, and the requirements of design and construction quality specifications are met;

s5, mounting pipe gallery

S51, preparation for installation

S511, checking the components transported to the site according to the component detail table before hoisting the steel components, checking and accepting the deformation condition of the components in the transportation process, making a record, and timely correcting the problems; for the foundation and the embedded foundation bolt, checking the rechecking axis position, height deviation, flatness and elevation, and then popping out the cross center line and the guiding and measuring elevation, wherein the details are shown in fig. 2 (a drawing and measuring schematic diagram of the elevation at the bottom of the column);

because the two aspects of manufacturing and installing the steel structure are involved, and the relation between civil engineering and the steel structure is also involved, the measuring tools between the civil engineering and the steel structure must be unified;

s512, measurement

In order to meet the accuracy of structural installation and the construction progress of a project, the selection of a measuring instrument and the simplicity, convenience and reliability of a measuring scheme are of great importance.

Basic inspection, paying-off and elevation block setting: because of the relation between civil engineering and steel structures, the measuring tools between the civil engineering and the steel structures must be unified and calibrated; the basic re-calibration location should use the axis control point and the reference point of the measuring axis; processing impurities on the surface of the foundation, and popping vertical and horizontal axes of the column on the surface of the foundation; after the elevation blocks are adjusted, pouring concrete in the range of the column bottom according to the elevation, and retesting the axis;

retesting the control points and axes of civil engineering handover, and correcting in time; measuring and releasing the required control line, and leading out the control line to ensure the visibility; detecting the external dimensions of the steel member according to relevant regulations before installation; the longitudinal and transverse axis measurement determines positioning points according to a total station, and the control points adopt the axis of the theodolite; after a steel ruler, a theodolite, a level and other measuring tools are checked, firstly, the positions of a beam and a column are determined according to the positions of a design drawing, then a steel structure mounting position line and an auxiliary line are released, and the steel structure mounting position line and the auxiliary line are marked by bright and firm colors;

s52, mounting the pipe gallery column:

hoisting a steel column by adopting a single machine rotation method, and righting a steel beam, turning over and lifting a plate by adopting a two-point plate lifting method; in order to ensure the hoisting safety and avoid the stop times of the crane, the steel members are hoisted according to the hoisting construction sequence of the advancing route, and the vertical members are hoisted firstly and the plane members are hoisted later during hoisting, so that the accumulated error of the longitudinal length installation of the pipe gallery is reduced;

the steel columns in the areas in charge of the two cranes are hoisted sequentially from the axis A by using the two cranes until all the steel columns are hoisted;

the steel column correction and the steel girder assembly should be carried out simultaneously in the process of hoisting the steel column; after the steel column is hoisted and corrected, hoisting the steel beam; when assembling, checking the strength and stability of the easy-to-deform component, and taking reinforcement measures if necessary; designing a node required to be tightly propped, wherein 70% of beams are required to be tightly attached to two contacted planes, checking by using a 0.3mm feeler gauge, ensuring that the sum of the areas of the insertion depths is not more than 30% of the total area, and the maximum gap of the edge is not more than 0.8mm, when other components and equipment need to be hoisted by using an installed structure, meeting the agreement of a design unit, taking measures to prevent the structure from being damaged, determining a main component of a geometric position, hoisting the main component on the design position, and performing primary correction and fixing before a lifting hook is loosened;

while hoisting the steel beams, the tie bars between every two steel beams are simultaneously installed after the steel columns and the steel beams are corrected, form a stable system with the rigid frame and sequentially hoist until the hoisting is finished;

s521, hoisting and correcting the steel column:

(1) the hoisting method of the steel column is similar to that of a common fabricated reinforced concrete column, manual lifting is adopted to assist in positioning under the condition that the hoisting time of the structure is short, and the steel column is hoisted by adopting a single-machine rotating method after the member is positioned, wherein the specific hoisting method is shown in figure 3 (a single-machine rotating method hoisting schematic diagram); in order to improve the hoisting efficiency, when the columns are stacked, three points of a binding point, a column base center and a foundation center of the columns are in a common arc shape as much as possible.

(2) The hoist hangs the post that the ligature is good slowly and hangs off the ground 20cm when lifting by crane and then decides temporarily, it is firm to check the hoist cable and the crane is stable, open the gyration brake simultaneously, then put the steel column down to 40 ~ 100mm from the installation face, aim at the datum line, instruct the crane to descend, insert the post anchor bolt temporary fixation, the steel column is through the initial correction after, wait to hang down straightness deviation control and can make the hoist unhook within 20mm, the straightness that hangs down of steel column is checked with the theodolite, if the deviation is rectified immediately, observe whether to break away between bottom and the elevation control block bundle at any time at the alignment in-process, in case cause the horizontal elevation error in the alignment in-process.

(3) The vertical correction of the post, the measurement is arranged on the vertical axis and the horizontal axis with two theodolites, the vertical flange plate or the central line at the bottom of the post is firstly aligned, then the vertical flange plate or the central line is gradually looked up to the top of the post, if the central line deviates from the sight line, the post is not vertical, the pull rope or the support can be commanded and adjusted, and the post can be vertical by beating and other methods. In practical work, rows of columns are often erected and then corrected; two theodolites can be respectively arranged at one side of the longitudinal axis and the transverse axis, the deviation from the central line is generally not more than 3m, and the vertical correction method of the steel column is shown in figure 4 (a schematic view of vertical correction of the steel column). When the vertical component is installed, the steel column needs to be rechecked and corrected.

S522, mounting the sizing block

(1) And accurately marking the position of the sizing block according to the position of each central line and the layout schematic diagram of the sizing block.

The thickness of the sizing block can be planed and cut a small amount of height difference of each bearing surface (the planing cutting amount is 5mm) according to the installed elevation requirement, then the supporting surface of the sizing block is shoveled, the contact surface reaches 70%, four corners are stable, the corresponding elevation is measured by a level gauge, the leveling is performed by a level of 0.05mm/m, and the basic surface treatment requirement of the lower leveling sizing block penetrating through the bolt is the same as that of the upper leveling sizing block.

(2) When each set of sizing blocks is planed and scraped, the sizing blocks are numbered according to the positions of the corresponding sizing blocks so as to avoid misplacement, the joints of each set of sizing blocks are ground by a coloring method, and the thickness of the joints is 25 multiplied by 25mm²Contact points are 3-5 points within the range, the contact area reaches more than 75%, a 0.05mm feeler gauge is used for stopping inserting, and if the feeler gauge is unqualified, the feeler gauge needs to be used for re-scraping (the feeler gauge can be used for scraping on a flat plate). Each set of sizing blocks should generally not exceed four, and in particular, five sizing blocks are individually allowed, wherein only one pair of inclined sizing blocks is allowed, and the sizing blocks after arrangement are leveled by a level and a ruler. And (3) before the concrete is poured for the second time, firmly welding each layer of the sizing blocks by electric welding.

S523, mounting of high-strength bolt

(1) Bolt installation

When the high-strength bolt is connected and installed, the number of temporary bolts and punching nails to be penetrated into each node is determined by calculation of loads possibly borne during installation, and the following regulations are met: 1/3 should not be less than the total number of the installation, and two temporary bolts should not be less than, and the number of the punching nails penetrating is not more than 30% of the temporary bolts.

High-strength bolts must be used as temporary bolts to prevent the torque coefficient from changing due to thread damage. The installation of the high-strength bolt should be carried out after the central position of the structural member is adjusted, and the penetrating direction of the high-strength bolt should be based on the construction convenience and strive for consistency. When installing high strength bolt, forbid to penetrate the bolt by force strictly. If the hole can not be freely penetrated, the hole is repaired by a reamer, the maximum diameter of the repaired hole is less than 1.2 times of the diameter of the bolt, and gas cutting reaming is strictly forbidden. When installing high strength bolts, the friction surfaces of the members should remain dry and should not work in the rain.

(2) Bolt fastening

The torque wrench used for high-strength bolt construction needs to be corrected before use, the torque error is not more than +/-5%, and the torque wrench can be used after being qualified. The tightening of the high-strength bolt is divided into initial tightening and final tightening, and the initial tightening torque is 50% of the construction torque; after the large hexagon head high-strength bolt is initially screwed or is screwed again, different colors are applied to coat a note on the nut so as to avoid missing screwing. After finishing screwing the high-strength large hexagon head bolt connection pair for 1 hour and within 48 hours, carrying out final screwing torque inspection, and carrying out spot inspection according to 10% of the number of nodes, wherein the number of the nodes is not less than 10; each node to be spot checked is 10% of the number of bolts and should not be less than 2. When the high-strength bolt is initially screwed and finally screwed, the bolts at the joint are screwed in a certain sequence. And the initial screwing and the final screwing are finished in the same day.

Usually, a large hexagonal high-strength bolt is adopted for connecting a steel beam and a column, and the friction surface of a component is protected to be dry and clean when the high-strength bolt is installed, so that the high-strength bolt cannot be operated in the rain. The tightening sequence should be applied from the center of the gusset plate to the edge, as shown in fig. 5 (schematic diagrams of steel beam correction, installation of column bottom sizing block, and high-strength bolt tightening), where a is a schematic diagram of steel beam correction, b is a schematic diagram of installation of column bottom sizing block, and c is a schematic diagram of high-strength bolt tightening. The two connecting pieces are arranged in a sequence of primary connection and secondary connection, the H-shaped steel component is arranged in a sequence of an upper flange, a lower flange and a compound plate, and the tightening sequence of the upper beam and the column joint of the same column is that the upper beam and the column joint is arranged firstly, the lower beam and the column joint is arranged secondly, and finally, the middle beam and the column joint is arranged secondly. The bolt-up degree that excels in can be controlled with electric spanner, and its exposure thread is detained and must not be less than 2 and detains, and all installation screws all must not adopt the gas cutting reaming, when surpassing the deviation of allowances and causing connecting bolt can not the break-through, and usable reamer is maintained, but the maximum diameter after maintaining should be less than 1.2 times of bolt diameter, should prevent during the reamed hole that iron fillings from falling into the plate and fold the gap. The bolt installed on the same day is required to be screwed up at the end of the same day.

After the hoisting is completed, the verticality and levelness between the components are adjusted, and in order to ensure the correct alignment between the continuous components, the supports between the columns and the horizontal supports are required to be installed and adjusted in time. The adjustment of the strut should release the locking of one strut to the other and when the column has reached verticality the strut should be finally locked to a "taut" condition without the bracing lock being so tight as to damage the component. In a word, the inclined strut can be locked just behind the verticality of all the components to be adjusted.

(3) The connection requirement of the high-strength bolt is as follows:

all components are connected with a contact surface, and after sand blasting treatment, the anti-slip coefficient of a friction surface of the components is as follows: 0.45 of Q235 steel and 0.50 of Q345 steel; an anti-slip coefficient experiment should be performed before construction. The processing, transportation, deposit of component need guarantee that friction surface sandblast effect meets the requirements, need before the installation to inspect after qualified, can carry out the high-strength bolt and assemble.

S524, cleaning and overhauling:

before leaving the field every day, metal garbage such as waste nails, sundries and the like is cleaned to prevent oxidation and rusting, the sundries are completely cleaned after the whole process is finished, whether the finished place is finished according to the requirement is checked, and if the finished place is not finished according to the requirement, the metal garbage is immediately repaired.

S53, hoisting and correcting steel beam

(1) The steel beam components are transported to the site and assembled firstly, a two-point turning-over plate lifting method is adopted when the steel beam needs to be turned over and lifted, and the lifting of the plates is temporarily assisted by using short steel pipes and square timbers manually. After the steel beam is turned over and in place, multiple trial lifting is needed, sling wires are bound again in time, the crane must be lifted slowly during trial lifting, the stress on the positions of lifting points is uniform, the steel beam is not deformed to be in an optimal state, and the steel beam is lifted and rotated to a designed position after the requirement is met; pulling a control rope pre-buckled on the girder by manpower on the ground, and fixing the hole position of the column girder by using plate tongs after rotating in place; four temporary fixing wind cables are additionally arranged on the first steel beam, the second steel beam is temporarily fixed by a connecting beam, more than five channels (planned to be 1-5 shaft tie rods) are arranged on a steel structure project with the span of about 24 meters, and the verticality of the steel structure project is checked by a hanging hammer while the steel structure project is fixed. The steel beam is lifted, specifically as shown in fig. 6 (schematic lifting diagram of steel beam), where a is a position before lifting, b is a position during lifting, and c is a position after alignment (positioning).

(2) When the steel beam is hoisted, the steel column is rechecked, a calabash-pull steel wire rope is generally adopted for checking, and the rope can be loosened after the girder is installed.

S54, allowable deviation of pipe gallery installation

The allowable deviation value of the pipe gallery installation accords with the specification of table 1 (allowable deviation of the pipe gallery installation), all the upright columns are checked, and the diagonal lines of the beam and the vertical face are spot-checked by category by 10 percent and are not less than 3.

TABLE 1 piping lane installation tolerances

S6, secondary grouting of foundation

(1) Before irrigation, the center of the steel structure frame is retested once, and secondary irrigation can be carried out within an adjustable range. The irrigation height is required according to drawings, and unified command is needed to take charge of comprehensive inspection and coordination matters of civil engineering and installation work.

Roughening the surface of the foundation concrete, blowing the foundation concrete clean, moistening the foundation concrete, and finishing spot welding of the sizing block without impurities, paint and oil stains; the interior of a foundation bolt hole is cleaned up and free of impurities, a foundation bolt base plate and concrete are in good contact, and a nut, exposed outside the foundation bolt, is additionally provided with a sleeve; before the concrete strength of the basic secondary pouring layer does not reach 50% of the designed strength, impact work is not allowed, and before the concrete strength of the basic secondary pouring layer does not reach 80% of the designed strength, the foundation bolt is not allowed to be tightened.

The cement used for the secondary pouring concrete is preferably micro-expansive cement, and an accelerating agent is not generally used, and if the cement is necessary to be used, the cement is approved by experiments and related technical departments. The secondary irrigation should be continuous without interruption. After pouring, the mortar splashed on the surfaces of the column bottom plates and the bolts is immediately wiped clean and maintained as required.

(2) After the main steel structure is hoisted and corrected, grouting can be performed within three days after correction so as to avoid displacement of the structure body due to other reasons, the grouting material is fine aggregate concrete, the column bottom plate is in complete contact with the foundation, and the grade of the grouting concrete is one grade higher than that of the column concrete. The preparation work before grouting, the over-high position of the concrete surface is removed to ensure that the grouting thickness is kept at least above 4cm, and the adverse substances such as fine substances, grease, soil and the like on the concrete surface are removed to keep proper roughness. The form panels on one and both sides also need to be raised above the panel surface with a gap and be slightly inclined to allow insertion of the wood bar or steel bar. The grouting material must be mixed by a mixer, and if it is mixed by hand, it lacks fluidity and tends to increase water, causing a risk of shrinkage. Once poured, the work must be continued until the grout exits from the surroundings, and the grout must start from one side and must not be interrupted until it is not completed. After perfusion, the cells were maintained in a wet state for at least seven days.

S7, coating the pipe rack:

(1) before coating, firstly checking whether the surface treatment of the steel meets the requirement of the rust prevention grade, generally not lower than Sa2.5, then checking whether the phenomenon of rust return or recontamination still exists, if not, retreatment is needed, and simultaneously spraying primer within 12 hours after rust removal. The anticorrosion temperature is 10-30 deg.C, relative humidity is not more than 80%, and construction is prohibited under the conditions of rain, fog, snow and large amount of dust.

(2) For the parts which do not need to be painted and are prohibited from painting, the parts are covered in advance by a gummed paper tape so as to avoid painting. Before the barrel of the paint is opened, the name, specification, color and the like of the paint are verified, whether the storage period is exceeded or not is judged, and otherwise, the paint can be used after being verified to be qualified; stirring before opening the barrel, observing whether the caking exists or not, and not using the material; after stirring, the viscosity of the mixture is measured, and the viscosity is adjusted to be within the range specified by construction requirements by using a matched diluent, wherein the lower limit is set in summer, and the upper limit is set in winter.

(3) Coating an anticorrosive layer on a pipe rack constructed in a severe cold area according to the standard requirement, wherein the thickness of the anticorrosive layer of the pipe rack in the severe cold area is generally not less than 240um, the epoxy zinc-rich primer is not less than 50um, the epoxy zinc-rich intermediate paint is not less than 140um, and the polyurethane finish paint is not less than 50 um; the special parts such as the high-strength bolt connecting surface, the column base bottom plate and the foundation contact surface are not coated with anticorrosive paint, and the places with fireproof requirements are coated with fireproof paint, so that the whole process of the construction method of the public pipe gallery in the industrial plant area in the severe cold area is completed.

The standardized operation method of the construction method of the public pipe gallery in the industrial plant area in the severe cold area is effectively applied to a plurality of projects, and the proved economic benefit is obvious.

Through implementation, the construction method for the common pipe gallery of the industrial plant area in the severe cold area adopts the steps of preparing before S1 construction, excavating S2 foundation earthwork, binding and pouring concrete of S3 foundation steel bars, embedding anchor bolts, backfilling and accepting S4 foundation earthwork, installing S5 pipe gallery, secondarily grouting S6 foundation, coating S7 pipe gallery frames and the like, and realizes the high-quality standardized construction method for the common pipe gallery of the industrial plant area in the severe cold area. Compared with the traditional construction method, the construction method has the advantages of strong pertinence, easy operation and good control, and greatly saves construction manpower, machines and auxiliary materials; a large amount of high-altitude operation is carried out on the ground, so that the danger of the high-altitude operation is greatly reduced; because of the construction on the ground, the safety of constructors is increased, which is beneficial to improving the welding quality and is convenient for taking measures for ensuring the quality; the trouble of setting up and removing a large amount of temporary supports and the trouble of working at high altitude from top to bottom are reduced, so that the working efficiency is improved. Meanwhile, the construction method can ensure good engineering quality, particularly, the corrosion resistance of the pipe rack in the severe cold region is greatly improved by adopting the steel Q235D, the advantages of the construction method on engineering progress and cost control are obvious, labor cost, material cost and hoisting cost are greatly reduced, construction cost is reduced, and construction period is shortened.

The foregoing is an illustrative description of the invention, and it is clear that the specific implementation of the invention is not restricted to the above-described manner, but it is within the scope of the invention to apply the inventive concept and solution to other applications without substantial or direct modification.

Claims (7)

1. A construction method for a public pipe gallery of an industrial plant area in a severe cold area is characterized by comprising the following steps:

s1, preparation before construction:

s11, compiling a basic construction scheme and a steel structure installation scheme, and after approval, organizing professional technicians to be familiar with drawings and acceptance criteria, knowing characteristics and key points of the whole construction process, participating in drawing review, compiling construction budget, and providing a labor force plan, a mechanical equipment plan and a construction network progress chart;

s12, checking and accepting the approach materials, arranging the operation environment of the construction site, familiarizing with the steel structure installation process and quality requirements, and performing targeted technical background for constructors; preparing various materials required by construction, supporting a formwork, and reinforcing a used template, a steel pipe and a fastener;

s13, dividing construction areas according to the actual conditions of the project, making a flow process diagram, checking the actual conditions of the site by contrasting the construction diagram, sorting out the parts which cannot be constructed according to the design intention in advance, and negotiating the construction method with the design in advance;

s2, excavating foundation earthwork:

the pipe gallery foundation is an independent foundation, and foundation earth excavation is carried out by adopting a method of combining a backhoe excavator and a dump truck for carrying earth; the earthwork with better soil quality is transported to a specified soil piling position by a dump truck; the foundation pit slope coefficient is 1: 1.2, reserving 300mm of an outer side line of a foundation pit cushion layer as a construction working surface, and manually cleaning a base with 200-300 mm of length during foundation earthwork excavation;

s3, binding and pouring concrete for foundation steel bars and embedding foundation bolts:

s31, blanking is carried out in the steel bar processing shed according to the design requirements of a drawing, steel bars are bound, then the steel bars are transported to a construction operation point for installation, and the semi-finished materials which cannot be prefabricated are transported to the construction operation point for binding;

s32, building a bearing stratum;

s33, filling a layer of plain concrete C20 under the foundation bearing platform, and binding the foundation bearing platform steel bars after the strength is achieved; then pouring concrete C35, after the concrete strength of the bearing platform meets the requirement, supporting a template, fixing foundation bolts at the upper opening of the reinforcement cage, and then pouring concrete C35;

s34, commercial mixing is adopted for the concrete, when the concrete is vibrated, the inserting distance of the vibrating rods is 400mm, the vibrating time is 15-30S, and the pouring interval time of the concrete between the upper layer and the lower layer is not more than the initial setting time of the concrete;

s35, after the strength of the concrete column meets the form removal requirement, removing the form in time and coating epoxy asphalt with the thickness of 300 mu m on the surfaces of the reinforced concrete column and the foundation beam;

s4, backfilling and acceptance of foundation earthwork:

backfilling earthwork, checking the foundation, handling the acceptance of the concealed project and making an acceptance record; selecting soil dug in the foundation pit as the soil quality of the earthwork backfill; the foundation earthwork backfill is artificially compacted and filled in layers, each layer is less than or equal to 300mm, and the compaction coefficient is more than or equal to 94 percent;

s5, mounting pipe gallery

S51, preparation for installation

S511, checking the components transported to the site according to component detail tables before hoisting the steel components, and checking and accepting deformation conditions of the components in the transportation process; for the foundation and the embedded foundation bolts, checking the position of a rechecking axis, height deviation, flatness and elevation, and then popping out a cross center line and guiding and measuring the elevation;

s512, measurement

Basic inspection, paying off and elevation block setting; retesting the control points and axes of civil engineering handover, and correcting in time; measuring and releasing the required control line, and leading out the control line to ensure the visibility; detecting the external dimensions of the steel member according to relevant regulations before installation; the longitudinal and transverse axis measurement determines positioning points according to a total station, and the control points adopt the axis of the theodolite; after a steel ruler, a theodolite and a level are checked, firstly, the positions of a beam and a column are determined according to the positions of a design drawing, then a steel structure mounting position line and an auxiliary line are released, and the steel structure mounting position line and the auxiliary line are marked by bright and firm colors;

s52, mounting the pipe gallery column:

hoisting a steel column by adopting a single machine rotation method, and righting a steel beam, turning over and lifting a plate by adopting a two-point plate lifting method; while hoisting the steel beams, the tie bars between every two steel beams are simultaneously installed after the steel columns and the steel beams are corrected, form a stable system with the rigid frame and sequentially hoist until the hoisting is finished;

s521, hoisting and correcting the steel column:

hoisting the steel column, adopting manual lifting to assist in positioning, and hoisting the component in position by adopting a single-machine rotating method; vertically correcting the column, namely arranging two theodolites on a longitudinal axis and a transverse axis for measurement, and then correcting;

s522, mounting a sizing block:

accurately marking the position of the sizing block according to the position of each central line and the layout schematic diagram of the sizing block; then carrying out installation, slicing and leveling of the sizing blocks, and finally carrying out electric welding to firmly weld each layer of sizing blocks by electric welding before the concrete is poured for the second time;

s523, mounting of the high-strength bolt:

when the high-strength bolts are connected and installed, the number of temporary bolts and punching nails to be penetrated into each node is determined by calculation of loads possibly borne during installation; the torque wrench used for the fastening construction of the high-strength bolt needs to be corrected before use, the torque error is less than or equal to +/-5 percent, and the torque wrench can be used after being qualified; the tightening of the high-strength bolt is divided into initial tightening and final tightening, and the verticality and the levelness between the components are adjusted immediately after the hoisting is finished; all components of the high-strength bolt are connected with the contact surface, after sand blasting treatment, an anti-slip coefficient experiment should be carried out before construction, and after inspection is qualified, high-strength bolt assembly can be carried out;

s524, cleaning and overhauling:

before leaving the field every day, metal garbage such as waste nails, sundries and the like is cleaned to prevent oxidation and rusting, the sundries are completely cleaned after the metal garbage is completely finished, whether the finished place is finished according to requirements is checked, and if the metal garbage is not finished, the metal garbage is immediately repaired;

s53, hoisting and correcting the steel beam:

the steel beam components are transported to the site and are firstly assembled, a two-point turning-over plate lifting method is adopted when the steel beams need to be turned over and lifted, and the plates are temporarily assisted by manpower by using short steel pipes and square timbers; when the steel beam is hoisted, the steel column needs to be rechecked, a calabash steel wire rope cable is generally adopted for inspection, and the cable can be loosened after the girder is installed;

s54, allowable deviation of pipe gallery installation

The allowable deviation value of the installation of the pipe gallery meets the specified requirement, all the upright columns are inspected, and the diagonal lines of the beam and the vertical face are spot-inspected by 10% according to the type and need to be more than or equal to 3;

s6, foundation secondary grouting:

the center of the steel structure frame is retested for one time before irrigation, and secondary irrigation can be carried out within an adjustable range; the cement used by the secondary poured concrete adopts micro-expansion cement, and an accelerator is not used; the grouting material is fine stone concrete, so that the column bottom plate is completely contacted with the foundation, and the grade of the grouting concrete is higher than that of the column concrete by one grade; the secondary irrigation work is continuously carried out without interruption; after pouring, the mortar splashed to the surfaces of the column bottom plates and the bolts is immediately wiped clean and maintained according to requirements;

s7, coating the pipe rack:

before coating, checking whether the surface treatment of the steel meets the requirement of the rust prevention grade and is not lower than Sa2.5, then checking whether the phenomenon of rust return or recontamination still exists, if not, retreating is needed, and simultaneously spraying primer within 12 hours after rust removal; then, for parts which do not need to be coated and are prohibited to be painted, masking the parts by using a gummed paper tape in advance so as to avoid painting; and finally, coating an anticorrosive layer on the pipe rack constructed in the severe cold area according to the standard requirement, thereby completing the whole process of the construction method of the public pipe rack in the industrial plant area in the severe cold area.

2. The method for preparing the common pipe gallery construction method for the industrial plant area in the severe cold region according to claim 1, wherein in the step S32 of constructing the bearing layer, the pebble layer is taken as the bearing layer.

3. The method for preparing the construction method of the utility pipe gallery in the industrial plant area in the severe cold region according to claim 1, wherein in the step S32 of constructing the bearing stratum, if the base elevation of the basic design is not higher than the bearing stratum, graded broken stones are used for backfilling, and the layers are rolled and compacted to the design elevation; wherein the layering thickness is 300mm, the compaction coefficient is 0.97, and the bearing capacity characteristic value is 200 kPa.

4. The preparation method of the construction method of the utility pipe gallery in the industrial plant area in the severe cold region as claimed in claim 1, wherein in step S512, the concrete steps of foundation inspection, paying off and elevation block setting are as follows: firstly, the basic re-calibration positioning uses an axis control point and a reference point of a measuring axis; then, processing impurities on the surface of the foundation, and popping longitudinal and transverse axes of the column on the surface of the foundation; and finally, after the elevation blocks are adjusted, pouring concrete in the range of the column bottom according to the elevation, and retesting the axis.

5. The method for preparing the construction method of the utility pipe gallery in the industrial plant area of the severe cold region as claimed in claim 1, wherein in step S521, the steel columns are hoisted and corrected by the following detailed steps:

(1) hoisting the steel column, adopting manual lifting to assist in positioning, and hoisting the component in position by adopting a single-machine rotating method; in order to improve the hoisting efficiency, when the columns are stacked, three points of binding points of the columns, the centers of column bases and the center of a foundation are in a common arc as much as possible;

(2) when in lifting, the bound column is slowly lifted up by the crane for 20cm from the ground and then is temporarily set, the firmness of the sling and the stability of the crane are checked, and meanwhile, a rotary brake is opened; then, placing the steel column down to be 40-100mm away from the installation surface, aligning with the datum line, commanding the crane to descend, and inserting the column into the anchoring bolt for temporary fixation; after the steel column is primarily corrected, the crane is unhooked when the perpendicularity deviation is controlled within 20mm, the perpendicularity of the steel column is checked by a theodolite, the deviation is corrected, and whether the gap between the bottom and the elevation control block is empty or not is observed at any time in the correction process so as to prevent a horizontal elevation error from being caused in the correction process;

(3) vertically correcting the column, namely arranging two theodolites on a longitudinal axis and a transverse axis for measurement, aligning a vertical flange plate or a central line at the bottom of the column, and gradually looking up to the top of the column; if the midline deviates from the sight line, the post is not vertical, the adjusting pull rope or the support can be commanded, and the post can be vertical by a beating method; in practical work, rows of columns are often erected and then corrected; at this time, two theodolites can be respectively arranged on one side of the longitudinal axis and the transverse axis, the distance deviating from the center line is less than or equal to 3m, and when the vertical component is installed, the steel column needs to be rechecked and corrected.

6. The method for preparing the common pipe gallery construction method for the industrial plant area in the severe cold region as claimed in claim 1, wherein in step S522, installing, slicing and leveling the sizing block, wherein the detailed method comprises the following steps: the thickness of the sizing block is subjected to a small amount of slicing on the height difference of each bearing surface according to the installed elevation requirement, the slicing amount is 5mm, then the supporting surface of the sizing block is flatly shoveled, the contact surface reaches more than 70%, four corners are stable, the corresponding elevation is measured by a level gauge, the leveling is performed by using the level of 0.05mm/m, and the basic surface treatment requirement of the lower leveling sizing block penetrating through the bolt is the same as that of the upper leveling sizing block; when each set of sizing blocks is planed and scraped, the sizing blocks are numbered according to the positions of the sizing blocks so as to avoid misplacement, the joints of each set of sizing blocks are ground by a coloring method, and the thickness of the joints is 25mm multiplied by 25mm²The contact area reaches more than 75 percent when the contact point is 3-5 points in the range; leveling the arranged sizing block by using a level meter and a ruler.

7. The method for preparing the common pipe rack construction method for the industrial plant area in the severe cold region as claimed in claim 1, wherein in step S7, the thickness of the corrosion-resistant layer of the pipe rack is more than or equal to 240um, wherein the thickness of the epoxy zinc-rich primer is more than or equal to 50um, the thickness of the epoxy zinc-rich intermediate paint is more than or equal to 140um, and the thickness of the polyurethane finish paint is more than or equal to 50 um.

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