阅读说明：本技术 一种屋盖钢结构梭形柱及其施工方法 (Shuttle-shaped column of roof steel structure and construction method thereof ) 是由 彭志勇 罗岗 贾成亮 张明 卢海丰 陈路 刘云飞 谢会雪 王罡 张伟 刘时新 于 2021-08-25 设计创作，主要内容包括：一种屋盖钢结构梭形柱及其施工方法,梭形柱两端铰接,当钢梁完全焊接完成后,结构形成完整传力体系。本发明通过对大型履带吊配置、胎架基础设计、支座锁定设计及安装顺序设计,实现超高梭形柱设置两根胎架、分两段吊装即保证梭形柱顺利就位,采用大型履带吊即可安装就位,约四个小时即可安装完成。(A shuttle-shaped column of roof steel structure and its construction method features that two ends of the shuttle-shaped column are hinged together, and when the steel beam is welded completely, the structure forms a complete force-transferring system. According to the invention, through configuration of the large crawler crane, design of the jig frame foundation, design of the support locking and design of the installation sequence, the ultrahigh shuttle-shaped column is provided with two jig frames, and is hoisted in two sections, so that the shuttle-shaped column is ensured to be smoothly in place, the large crawler crane can be installed in place, and the installation can be completed in about four hours.)

1. A construction method of a steel structure shuttle-shaped column of a roof is characterized in that:

the room cover steel structure shuttle-shaped column is a row of two-way inclined shuttle-shaped columns (4) which are hinged with the ground and stand on one side of the existing structure (1), the shuttle-shaped column (4) is divided into an upper section and a lower section which are respectively a column upper section (41) and a column lower section (42), the diameter of the column lower section (42) is gradually increased from bottom to top, the diameter of the column upper section (41) is gradually decreased from bottom to top,

the construction steps are as follows:

step one, constructing an existing structure (1);

collecting preparation materials before construction of the fusiform column (4);

step three, measuring and paying off: accurately calculating the coordinates of the shuttle-shaped column support (11) according to a design drawing and the coordinate reference points; then pouring and constructing a fusiform column support (11) at a design position;

fourthly, ramming plain soil, and treating a field backfill layer and a road surface:

designing a projection zone covered by a steel beam connected with the shuttle-shaped column to be within the range of a hoisting road surface (12) for a crawler crane (10) to walk, wherein the hoisting road surface comprises a plain soil tamping layer (13) at the bottom and a field backfill layer (13), the part is laminated and rolled according to a backfill scheme, and the projection zone further comprises a paving foundation box (14) which is full at the upper side of the hoisting road surface;

fifthly, assembling the crawler crane (10) and standing on the lifting road surface (12);

step six, manufacturing a fusiform column and installing a fusiform column base:

prefabricating and processing a shuttle-shaped column (4) of reinforced concrete in a factory, after the concrete is poured and demoulded and maintained to strength, welding a shuttle-shaped column base (43) at the bottom of the shuttle-shaped column; the base is locked in advance in a factory, before the steel beam connected with the shuttle-shaped column is installed, the base hinged locking plate is not allowed to be opened, and finally the base hinged locking plate is transported to a construction site;

designing and calculating a shuttle-shaped column temporary supporting structure according to indexes of the shuttle-shaped column, constructing the shuttle-shaped column temporary supporting structure (15) beside a shuttle-shaped column support in a lifting pavement range, constructing a concrete reinforcing layer (28) below the installation position of the shuttle-shaped column temporary supporting structure (15) on a plain soil tamping, plain soil tamping and field backfill layer (13), and welding the bottom of the shuttle-shaped column temporary supporting structure (15) with a roadbed box (14);

the temporary shuttle-shaped column supporting structure (15) is a high-low support combination and comprises a low support (16) and a high support (17), the low support (16) is close to the existing structure (1), the low support (16) is positioned on the front side of the shuttle-shaped column support (11), the height of the low support (16) is smaller than that of the column lower section (42), the high support (17) is positioned on the front side of the low support (16), a low support adjusting beam (18) is arranged at the top of the low support (16), a high support adjusting beam (29) is arranged at the top of the high support (17), a structure pull-connection beam (18) is arranged between the top of the low support (16) and the existing structure (1), a support pull-connection beam (19) is arranged between the low support and the high support, and a cable rope is arranged between the temporary shuttle-shaped column supporting structure (15) and the ground;

step eight, constructing the fusiform column:

the crawler crane walks to the position near the shuttle-shaped column support, then the lower column section (42) is hoisted by adopting a steel wire rope and a manual hoist, the steel wire rope is used as a main rope, the manual hoist is used as an auxiliary rope to adjust the angle, after the crawler crane is hoisted in place, a shuttle-shaped column base (43) at the bottom of the lower column section (42) is welded with the shuttle-shaped column support (11), then the upper part of the lower column section (42) is welded with the low-support adjusting beam (18), and finally the crawler crane loosens the hook;

step nine, the crawler crane walks to the position near the shuttle-shaped column support (11), then the upper column section (41) is hoisted by adopting a steel wire rope and a manual hoist, the steel wire rope is used as a main rope, the manual hoist is used as an auxiliary rope to adjust the angle, after the crawler crane is hoisted in place, the bottom of the upper column section (41) is fixedly connected with the top of the lower column section (42) so that the shuttle-shaped columns are connected into a whole, then the middle upper part of the upper column section (41) is welded with the high-support adjusting beam (29), and finally the crawler crane loosens the hook;

step ten, after the steel beam connected with the spindle-shaped column is hoisted, and before the crawler crane loosens the hook, the base hinged locking plate is removed.

2. The construction method of the shuttle-shaped column of the roof steel structure according to claim 1, characterized in that: the plain soil ramming and field backfill layer is backfilled by 2:8 lime soil, the compaction coefficient is 0.93, and the plain soil ramming and field backfill layer is compacted by static pressure of a small road roller for more than 3 times.

3. The construction method of the shuttle-shaped column of the roof steel structure according to claim 1, characterized in that: high support (17) are steel lattice column with low support (16), support draw and connect roof beam (19) between low support and the high support and be equipped with three altogether, including drawing steel lattice beam (191) that connect low support top and high support middle part, still including drawing beam column draw and connect roof beam (192) between low support adjusting beam and the high support, still including drawing and connecting between post draw and connect roof beam middle part and the high support lower part of low support adjusting beam (193).

4. The construction method of the shuttle-shaped column of the roof steel structure as claimed in claim 3, wherein: the cable wind rope comprises a column ground cable wind rope (20) connected with the middle part of the low support and the ground in a pulling mode and the middle part of the high support and the ground in a pulling mode, a node cable wind rope (21) connected between the connecting position of the steel lattice beam (191) and the steel lattice column and the ground in a pulling mode, and a column top cable wind rope (22) connected between the top of the high support and an existing structure in a pulling mode.

5. The construction method of the shuttle-shaped column of the roof steel structure according to claim 1, characterized in that: the low-support adjusting beam (18) and the high-support adjusting beam (29) are the same in structure and comprise a horizontal rectangular bottom frame (23), vertical supporting columns (24), inclined supporting rods (25), a supporting middle plate (26) and a group of knife boards (27).

6. The construction method of the shuttle-shaped column of the roof steel structure as claimed in claim 5, wherein: the horizontal rectangular bottom frame (23) is fixedly connected with the tops of the low support adjusting beam and the high support adjusting beam, the number of the vertical supporting columns (24) is two, the vertical supporting columns are respectively and fixedly connected to the middle parts of two longitudinal frames of the horizontal rectangular bottom frame (23), the inclined supporting rods (25) are provided with three pairs, wherein two pairs of the vertical supporting columns are respectively arranged between the upper part of the vertical supporting column (24) and the two transverse frames of the horizontal rectangular bottom frame (23), the transverse two ends of the middle supporting plate (26) are respectively and fixedly connected between the two vertical supporting columns (24), the rest pair of inclined supporting rods (25) are arranged between the bottom of the middle supporting plate (26) and the middle parts of the two transverse frames, embedded parts welded with the knife boards (27) are embedded in the bottoms of the fusiform columns, the group of knife boards (27) are arranged at intervals along the transverse direction, and one side of the knife boards, which faces the shuttle-shaped column, is a bevel edge which is adapted to the corresponding connecting position of the shuttle-shaped column (4) by an inclination angle.

7. The construction method of the shuttle-shaped column of the roof steel structure as claimed in claim 5, wherein:

twelfth, unloading the temporary support structure of the shuttle-shaped column; the cutting board is cut off, the height of each cutting is controlled according to the unloading displacement amount of the supporting position, the structure is enabled to be uniformly and slowly settled, settlement mutation and anisotropic deformation of the structure are avoided, the structure is fully deformed and observation time is reserved for each cutting, the support is integrally removed after the structure does not generate downward displacement after the cutting of a certain step is completed, observation is continued after the unloading is completed, the structure is ensured to be safe and free of redundant deformation, and then the temporary supporting structure of the shuttle-shaped column is lifted and removed by a crane.

Technical Field

The invention belongs to the field of steel structure roof, and particularly relates to a steel structure roof shuttle-shaped column and a construction method thereof.

Background

With the continuous development of society, various building models are novel, large-span and ultrahigh-degree steel structures are widely used, the building land in China is short, the available space in the construction process is limited, adjacent buildings of building groups are very close, and great difficulty is brought to hoisting of large steel members.

During the installation of shuttle-shaped post in the installation unit among the room lid steel construction shuttle-shaped post, the shuttle-shaped post mostly sets up multisection support frame or full hall scaffold frame and carries out the segmentation hoist and mount, and the girder steel adopts interim support segmentation hoist and mount more, and the operation degree of difficulty is big, and the period of time of working is long.

Meanwhile, when the shuttle-shaped column is designed to be an ultrahigh component, if the deviation of the installation verticality exceeds 5mm, the steel beam node connected with the shuttle-shaped column cannot be installed in place, meanwhile, if the steel column is segmented and supported by a jig frame and is placed on the back filling soil of the fertilizer tank, the butt joint angle is difficult to control, and once the steel column has an inclination angle, the installation and positioning difficulty is more obvious.

According to the stress characteristic of the integral steel roof, two ends of the fusiform column are hinged, and when the steel beam is completely welded, the structure can form a complete force transmission system, so that the fusiform column is required to reduce the high-altitude installation time as much as possible, and the time of the unstable state of the component is reduced as much as possible. Therefore, a construction method for realizing high-precision hoisting and positioning of the two in high altitude and pin shaft connection of the two in high altitude aiming at a method for installing the steel structure shuttle-shaped column of the roof on the backfill soil is needed.

Disclosure of Invention

The invention aims to provide a room cover steel structure shuttle-shaped column and a construction method thereof, and aims to solve the technical problems that when the existing room cover steel structure shuttle-shaped column comprises the shuttle-shaped column, a plurality of sections of temporary support frames and full framing scaffold are adopted for segmental hoisting, the operation difficulty is high, and the construction period is long, and meanwhile, the technical problems that when the existing room cover steel structure shuttle-shaped column is hoisted on the backfill soil of a fertilizer tank, the butt joint angle is difficult to control, and the installation and positioning difficulty is more obvious are solved.

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

the shuttle-shaped column of the roof steel structure is a row of two-way inclined shuttle-shaped columns which are erected on one side of the existing structure and hinged with the ground, the shuttle-shaped column is divided into an upper section and a lower section which are respectively an upper section and a lower section, the diameter of the lower section of the column is gradually increased from bottom to top, the diameter of the upper section of the column is gradually decreased from bottom to top,

the construction steps are as follows:

step one, constructing an existing structure;

collecting preparation materials before the construction of the fusiform column;

step three, measuring and paying off: accurately calculating the coordinates of the shuttle-shaped column support according to a design drawing and the coordinate reference points; then pouring and constructing a fusiform column support at a design position;

fourthly, ramming plain soil, and treating a field backfill layer and a road surface:

the projection area that the girder steel of being connected with the fusiformis post covered is designed for the lifting road surface scope that supplies the crawler crane to walk, lifting road surface includes the plain soil tamp of bottom and place backfill layer, and this part rolls according to the backfill scheme layering, still includes the full basic case of paving in the upside on lifting road surface.

Fifthly, assembling the crawler crane and standing on a lifting road surface;

step six, manufacturing a fusiform column and installing a fusiform column base:

prefabricating and processing a shuttle-shaped column of reinforced concrete in a factory, after the concrete is poured and demoulded and maintained to strength, welding a base of the shuttle-shaped column at the bottom of the shuttle-shaped column; the base is locked in advance in a factory, before the steel beam connected with the shuttle-shaped column is installed, the base hinged locking plate is not allowed to be opened, and finally the base hinged locking plate is transported to a construction site;

designing and calculating a temporary support structure of the shuttle-shaped column according to the index of the shuttle-shaped column, constructing the temporary support structure of the shuttle-shaped column beside a support of the shuttle-shaped column in the range of a lifted pavement, constructing a concrete reinforcing layer below the installation position of the temporary support structure of the shuttle-shaped column and on a plain soil tamping and field backfill layer, and welding the bottom of the temporary support structure of the shuttle-shaped column with a roadbed box;

the temporary support structure of the shuttle-shaped column is a high-low support combination and comprises a low support and a high support, the low support is close to an existing structure, the low support is positioned on the front side of a support of the shuttle-shaped column, the height of the low support is smaller than that of the lower section of the column, the high support is positioned on the front side of the low support, the top of the low support is provided with a low support adjusting beam, the top of the high support is provided with a high support adjusting beam, a structure connecting beam is arranged between the top of the low support and the existing structure, a support connecting beam is arranged between the low support and the high support, and a cable rope is arranged between the temporary support structure of the shuttle-shaped column and the ground;

step eight, constructing the fusiform column:

the crawler crane walks to the vicinity of the fusiform column support, then the lower section of the column is hoisted by adopting a steel wire rope and a manual hoist, the steel wire rope is used as a main rope, the manual hoist is used as an auxiliary rope to adjust the angle, after the crawler crane is hoisted in place, the fusiform column base at the bottom of the lower section of the column is welded with the fusiform column support, then the upper part of the lower section of the column is welded with the low-support adjusting beam, and finally the crawler crane loosens the hook;

step nine, the crawler crane walks to the vicinity of the support of the shuttle-shaped column, then the upper section of the column is hoisted by adopting a steel wire rope and a manual hoist, the steel wire rope is used as a main rope, the manual hoist is used as an auxiliary rope to adjust the angle, after the crawler crane is hoisted in place, the bottom of the upper section of the column is fixedly connected with the top of the lower section of the column, so that the shuttle-shaped column is connected into a whole, then the middle upper part of the upper section of the column is welded with the high-support adjusting beam, and finally the crawler crane loosens the hook;

step ten, after the steel beam connected with the spindle-shaped column is hoisted, and before the crawler crane loosens the hook, the base hinged locking plate is removed.

The plain soil ramming and field backfill layer is backfilled by 2:8 lime soil, the compaction coefficient is 0.93, and the plain soil ramming and field backfill layer is compacted by static pressure of a small road roller for more than 3 times.

The high support is steel lattice column with low supporting, support draw-connection roof beam between low support and the high support is equipped with three altogether, including drawing the steel lattice roof beam that connects low support top and high support middle part, still including drawing the beam column draw-connection roof beam that connects between low support adjusting beam and the high support, still including drawing the column draw-connection roof beam that connects low support adjusting beam middle part and high support lower part.

The cable wind rope comprises a column ground cable wind rope connected with the middle part of the low support and the ground and the middle part of the high support and the ground in a pulling mode, a node cable wind rope connected between the connecting position of the steel lattice beam and the steel lattice column and the ground, and a column top cable wind rope connected between the top of the high support and the existing structure in a pulling mode.

The low-support adjusting beam and the high-support adjusting beam have the same structure and comprise a horizontal rectangular bottom frame, vertical supporting columns, inclined supporting rods, a supporting middle plate and a group of cutting boards.

The horizontal rectangular underframe is fixedly connected to the tops of the low-support adjusting beam and the high-support adjusting beam, the number of the vertical support columns is two, the vertical support columns are respectively and fixedly connected to the middle portions of two longitudinal frames of the horizontal rectangular underframe, the inclined support rods are three pairs, two pairs of the inclined support rods are respectively arranged between the upper portions of the vertical support columns and two transverse frames of the horizontal rectangular underframe, the two transverse ends of the support middle plate are respectively and fixedly connected between the two vertical support columns, the rest pair of inclined support rods are arranged between the bottom of the support middle plate and the middle portions of the two transverse frames, embedded parts welded with the cutting boards are embedded in the bottoms of the shuttle-shaped columns, the set of cutting boards are arranged along the transverse interval, and one sides of the cutting boards, facing the shuttle-shaped columns, are bevel edges matched with the corresponding connection positions of the shuttle-shaped columns in inclination angle.

Twelfth, unloading the temporary support structure of the shuttle-shaped column; the cutting board is cut off, the height of each cutting is controlled according to the unloading displacement amount of the supporting position, the structure is enabled to be uniformly and slowly settled, settlement mutation and anisotropic deformation of the structure are avoided, the structure is fully deformed and observation time is reserved for each cutting, the support is integrally removed after the structure does not generate downward displacement after the cutting of a certain step is completed, observation is continued after the unloading is completed, the structure is ensured to be safe and free of redundant deformation, and then the temporary supporting structure of the shuttle-shaped column is lifted and removed by a crane.

Compared with the prior art, the invention has the following characteristics and beneficial effects:

the two ends of the fusiform column are hinged, so that the high-altitude installation time of the fusiform column component is required to be reduced as much as possible, and the time of the component in an unstable state is required to be reduced as much as possible. Therefore, the ultrahigh shuttle-shaped column has the hoisting problem without a referable technology, the elevation of the highest shuttle-shaped column can reach 58m, the lower section of the shuttle-shaped column is a spherical hinge support joint and is inclined in two directions, the inclination angle is 20-23 degrees, a connecting beam is not arranged between the shuttle-shaped column and an existing structure, the sectional installation difficulty is high during installation, the installation allowable deviation of a single steel column is H/1000 and not more than 25mm according to the steel structure construction quality acceptance standard, and through simulation analysis, if the installation verticality deviation of the shuttle-shaped column exceeds 5mm, the steel beam cannot be installed in place.

According to the invention, the arrangement of the large crawler crane, the design of the jig frame foundation, the design of the support locking and the design of the installation sequence are adopted, so that the ultrahigh shuttle-shaped column is provided with two jig frames and is hoisted in two sections, namely the shuttle-shaped column is ensured to be smoothly in place.

According to the invention, the large crawler crane is used, the sectional weight of the components is increased, the high-altitude butt joint is reduced, the foundation is reinforced by paving the roadbed box in the crane operation area, when the temporary support is supported on the backfill soil or other soft foundations, the mode of combining the concrete foundation and the roadbed box is adopted for the temporary support foundation, the foundation does not subside in the installation process, and the installation accuracy of the shuttle-shaped column is effectively ensured, so that the problem that the roadbed is soft when the large crawler crane operates on the backfill soil pavement is effectively solved.

The shuttle-shaped column is hoisted in two sections, a high-low combined lattice type temporary support is designed, and a support at the bottom of the shuttle-shaped column is locked in advance in the installation process, so that the installation deformation is reduced; the temporary support and the high-altitude butt joint quantity are avoided to be increased due to the fact that the number of the subsection sections is too large, the whole error is increased, the unstable fusiform column is reinforced through the temporary support, and the butt joint sections are reduced.

Compared with the construction quality, personnel equipment and material input conditions, construction period and the like of the traditional steel roof, the invention proves that the construction quality can be obviously improved, the labor cost is reduced, the construction period is shortened, the use of large machinery is effectively reduced, the construction period of a hoisted key circuit is decomposed to a ground-assembled non-key circuit, the high-altitude butt joint is less, the safety of operators is effectively ensured, the ground assembly is convenient to shield arc light, and the arc light pollution is effectively reduced. Ground assembly is convenient for collecting harmful substances generated by welding, reduces environmental pollution, greatly shortens construction period, saves mechanical cost and labor cost, and has obvious economic benefit. The installation accuracy of the invention exceeds the national standard, the industry standard and the project design requirement, the construction problem is solved, the consumption of manpower and resources is saved, and better economic benefit and social benefit are obtained.

Drawings

The present invention will be described in further detail with reference to the accompanying drawings.

Fig. 1 is a schematic structural view of the present invention.

FIG. 2 is an enlarged view of a portion of the attachment of the lifting surface to the crawler.

Fig. 3 is a schematic structural view of a lifted road surface.

Fig. 4 is a schematic structural view of a temporary support structure for the shuttle-shaped columns.

Fig. 5 is a partially enlarged view of fig. 4.

Fig. 6 is another side schematic view of the support adjustment beam.

Fig. 7 is a schematic plan view of fig. 6.

Fig. 8 is a schematic view of the completion of the hoisting of the lower section of the column.

Fig. 9 is a schematic view of the completion of the hoisting of the upper column section.

Reference numerals: the method comprises the following steps of 1-existing structure, 4-shuttle-shaped column, 41-column upper section, 42-column lower section, 43-shuttle-shaped column base, 6-steel beam, 10-crawler crane, 11-shuttle-shaped column support, 12-hoisting road surface, 13-plain soil tamping and field backfill layer, 14-roadbed box, 15-shuttle-shaped column temporary support structure, 16-low support, 17-high support, 18-low support adjusting beam, 19-support pull-connection beam, 191-steel lattice beam, 192-beam-column pull-connection beam, 193-inter-column pull-connection beam, 20-column ground cable wind rope, 21-node cable wind rope, 22-column top cable wind rope, 23-horizontal rectangular bottom frame, 24-vertical support column, 25-diagonal brace, 26-support middle plate, 27-knife plate, 28-concrete reinforcing layer and 29-high support adjusting beam.

Detailed Description

The embodiment of the steel structure shuttle-shaped column for the roof is shown in figure 1, the shuttle-shaped column is hinged with a foundation and a roof, the highest elevation is 58m, the shuttle-shaped column is a bidirectional inclined column, the inclination angle of a single column is 20-23 degrees, and no lateral support is provided except a foundation support node and a steel beam 6 pin shaft node.

The steel structure shuttle-shaped column of the roof is a row of two-way inclined shuttle-shaped columns 4 which are hinged with the ground and stand on one side of the existing structure 1, a steel beam 6 is hinged on the shuttle-shaped column 4, the shuttle-shaped column 4 is divided into an upper section and a lower section, the upper section 41 and the lower section 42 are respectively arranged on the upper section and the lower section, the diameter of the lower section 42 is gradually increased from bottom to top, and the diameter of the upper section 41 is gradually decreased from bottom to top.

The construction steps are as follows:

step one, constructing an existing structure 1;

step two, collecting preparation materials before the construction of the fusiform column 4; the material comprises: hoisting the foundation bearing capacity report of the operation area; the strength of the shuttle column foundation concrete is reported, and the strength of the shuttle column concrete foundation is up to 100%; measuring baseline and level point data; engineering design related documentation; timely clearing ground obstacles and the like near the crawler crane; the construction site is basically flat, and the endurance of the site meets the walking requirement of equipment; enough assembly sites are needed on site, and the endurance of the assembly sites is needed to meet the requirements.

Step three, measuring and paying off: accurately calculating the coordinates of the shuttle-shaped column support 11 according to a design drawing and the coordinate reference points; carrying out coordinate data rechecking; lofting by using a measuring instrument, pouring and constructing the fusiform column support 11 at a designed position, tracking and measuring by using a total station in the whole process during hoisting, and retesting the installed component in time after hoisting of the single component is completed.

Fourthly, ramming plain soil, and treating a field backfill layer and a road surface:

referring to fig. 2 to 3, a projected zone covered by steel beams connected to the shuttle-shaped columns is designed to be within a range of a hoisted road surface 12 on which the crawler crane 10 travels, the hoisted road surface including a plain soil tamped and ground backfill layer 13 at the bottom, which is laminated according to a backfill scheme, and a paving base box 14 filled at the upper side of the hoisted road surface. The plain soil ramming and field backfill layer is backfilled by 2:8 lime soil, the compaction coefficient is 0.93, and the plain soil ramming and field backfill layer is compacted by static pressure of a small road roller for more than 3 times.

The paving thickness is generally determined according to a test section, and the electric tamping machine is adopted for tamping when the field operation surface space is narrow and not suitable for small-sized mechanical operation. The bearing capacity of the backfill soil foundation reaches about 200 kpa.

Taking a 400T crawler crane as an example, when the 400T crawler crane runs on a soil layer, a roadbed box is fully paved on the ground, the specification of the roadbed box is 2mX6m, and the contact length between a crawler and the ground is 8.7 m. Calculated according to 10 roadbed boxes under the two crawler belts for bearing pressure, the contact area between the roadbed boxes and soil is 10X2X6=120mm²The self weight of the crawler crane is about 400t, the load is carried, the power coefficient is about 480t, and the bearing capacity of the foundation is about 40 kpa. Considering that a main arm is perpendicular to a crawler belt during hoisting, the single-side crawler belt compression limit value is 40X2=80kpa, and the foundation bearing capacity of a walking route of the crawler crane is required to be 80X1.2=96 kpa.

And step five, assembling the crawler crane 10 and standing on the hoisting road surface 12. The crawler crane mostly adopts the working condition of a main arm and an auxiliary arm. The parts of the crawler crane enter the field, are assembled and spliced by equipment manufacturers, the assembled and spliced parts need a relatively flat field with the length of 100 and the width of 10, and the parts are used after being tested and accepted by all the parties.

Step six, manufacturing a fusiform column and installing a fusiform column base:

prefabricating and processing the shuttle-shaped column 4 of reinforced concrete in a factory, after the concrete is poured and demoulded and maintained to strength, welding a shuttle-shaped column base 43 at the bottom of the shuttle-shaped column; the base is locked in advance in a factory, the hinged locking plate of the base is not allowed to be opened before the steel beam connected with the shuttle-shaped column is installed, and finally the base is transported to a construction site. The requirement on the installation accuracy of the base is high, the total station is adopted for whole-course tracking measurement in the installation process, the bottom plate of the base is 50mm thick, the welding amount is large, in order to reduce the damage of the welding heat to the concrete support, one welding seam is welded every time when the support is welded, the interval is 20 minutes, and another welding seam is welded until the whole base is welded.

And seventhly, designing and calculating a temporary shuttle-shaped column supporting structure according to the indexes of the shuttle-shaped column, constructing the temporary shuttle-shaped column supporting structure 15 beside a support of the shuttle-shaped column in the range of the lifted pavement, constructing a concrete reinforcing layer 28 below the installation position of the temporary shuttle-shaped column supporting structure 15 on the plain soil tamping, plain soil tamping and field backfill layer 13, and welding the bottom of the temporary shuttle-shaped column supporting structure 15 with the roadbed box 14. The concrete reinforcing layer is 300 mm.

The temporary support structure 15 of the fusiform column is a high-low support combination and comprises a low support 16 and a high support 17, the low support 16 is close to the existing structure 1, the low support 16 is positioned on the front side of the fusiform column support 11, the height of the low support 16 is smaller than that of the lower column section 42, the high support 17 is positioned on the front side of the low support 16, the top of the low support 16 is provided with a low support adjusting beam 18, the top of the high support 17 is provided with a high support adjusting beam 29, a structure tension connecting beam 18 is arranged between the top of the low support 16 and the existing structure 1, a support tension connecting beam 19 is arranged between the low support and the high support, the high support 17 and the low support 16 are both steel lattice columns, three support tension connecting beams 19 between the low support and the high support are arranged, the steel lattice beams 191 for connecting the top of the low support and the middle of the high support are included, and the beam column tension connecting beam 192 for connecting the low support adjusting beam and the high support are included, also includes a tension-connected beam 193 between the middle of the low-support adjusting beam and the high-support lower column.

A cable wind rope is arranged between the shuttle-shaped column temporary supporting structure 15 and the ground; the guy rope comprises a pillar-ground guy rope 20 connected with the middle part of the low support and the ground and the middle part of the high support and the ground, a node guy rope 21 connected between the connecting position of the steel lattice beam 191 and the steel lattice pillar and the ground, and a pillar-top guy rope 22 connected between the top part of the high support and the existing structure.

The low support adjusting beam 18 and the high support adjusting beam 29 have the same structure, and comprise a horizontal rectangular bottom frame 23, vertical supporting columns 24, diagonal supporting rods 25, a supporting middle plate 26 and a group of knife plates 27,

the horizontal rectangular bottom frame 23 is fixedly connected to the tops of the low-support adjusting beam and the high-support adjusting beam, the number of the vertical support columns 24 is two, the vertical support columns are respectively and fixedly connected to the middle portions of the two longitudinal frames of the horizontal rectangular bottom frame 23, the inclined support rods 25 are three, two pairs of the inclined support rods 25 are respectively arranged between the upper portions of the vertical support columns 24 and the two transverse frames of the horizontal rectangular bottom frame 23, the two transverse ends of the support middle plate 26 are respectively and fixedly connected between the two vertical support columns 24, the rest pair of inclined support rods 25 are arranged between the bottom of the support middle plate 26 and the middle portions of the two transverse frames, embedded parts welded with the knife plate 27 are embedded in the bottom of the shuttle-shaped column, the knife plate set 27 is arranged at transverse intervals, and one side of the knife plate facing the shuttle-shaped column is an inclined edge corresponding to the inclined angle of the corresponding connection position of the shuttle-shaped column 4.

Step eight, constructing the fusiform column:

referring to fig. 8, the crawler crane travels to the vicinity of the fusiform column support, then the lower column section 42 is hoisted by using a steel wire rope and a manual hoist, the steel wire rope is used as a main rope, the manual hoist is used as an auxiliary rope to adjust the angle, after the column is hoisted in place, the fusiform column base 43 at the bottom of the lower column section 42 is welded with the fusiform column support 11, then the upper part of the lower column section 42 is welded with the low-support adjusting beam 18, and finally the crawler crane loosens the hook. In the hoisting process of the fusiform column, hoisting points are accurately simulated and calculated.

Step nine, referring to fig. 9, the crawler crane walks to the vicinity of the shuttle-shaped column support 11, then the column upper section 41 is hoisted by using a steel wire rope and a manual hoist, the steel wire rope is used as a main rope, the manual hoist is used as an auxiliary rope to adjust the angle, after the crawler crane is hoisted in place, the bottom of the column upper section 41 is fixedly connected with the top of the column lower section 42, so that the shuttle-shaped columns are connected into a whole, then the middle upper part of the column upper section 41 is welded with the high-support adjusting beam 29, and finally the crawler crane loosens the hook. In the hoisting process of the fusiform column, hoisting points are accurately simulated and calculated.

Step ten, after the steel beam connected with the spindle-shaped column is hoisted, and before the crawler crane loosens the hook, the base hinged locking plate is removed.

Step eleven, unloading the temporary support structure of the fusiform column; the cutting board is cut off, the height of each cutting is controlled according to the unloading displacement amount of the supporting position, the structure is enabled to be uniformly and slowly settled, settlement mutation and anisotropic deformation of the structure are avoided, the structure is fully deformed and observation time is reserved for each cutting, the support is integrally removed after the structure does not generate downward displacement after the cutting of a certain step is completed, observation is continued after the unloading is completed, the structure is ensured to be safe and free of redundant deformation, and then the temporary supporting structure of the shuttle-shaped column is lifted and removed by a crane.