CN114809310B - Large-span steel truss high-altitude integral variable-angle jacking construction method - Google Patents
Large-span steel truss high-altitude integral variable-angle jacking construction method Download PDFInfo
- Publication number
- CN114809310B CN114809310B CN202210720064.3A CN202210720064A CN114809310B CN 114809310 B CN114809310 B CN 114809310B CN 202210720064 A CN202210720064 A CN 202210720064A CN 114809310 B CN114809310 B CN 114809310B
- Authority
- CN
- China
- Prior art keywords
- jacking
- net rack
- support
- steel
- frame
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 229910000831 Steel Inorganic materials 0.000 title claims abstract description 176
- 239000010959 steel Substances 0.000 title claims abstract description 176
- 238000010276 construction Methods 0.000 title claims abstract description 33
- 238000000034 method Methods 0.000 claims abstract description 56
- 238000003466 welding Methods 0.000 claims abstract description 9
- 238000006073 displacement reaction Methods 0.000 claims description 37
- 230000001360 synchronised effect Effects 0.000 claims description 22
- 238000005452 bending Methods 0.000 claims description 5
- 239000010720 hydraulic oil Substances 0.000 claims description 5
- 230000001502 supplementing effect Effects 0.000 claims description 5
- 238000009434 installation Methods 0.000 abstract description 11
- 238000010586 diagram Methods 0.000 description 9
- 238000012544 monitoring process Methods 0.000 description 5
- 239000003921 oil Substances 0.000 description 5
- 238000004364 calculation method Methods 0.000 description 3
- 240000009087 Crescentia cujete Species 0.000 description 2
- 235000005983 Crescentia cujete Nutrition 0.000 description 2
- 235000009797 Lagenaria vulgaris Nutrition 0.000 description 2
- 230000002159 abnormal effect Effects 0.000 description 2
- 230000000386 athletic effect Effects 0.000 description 2
- 230000001186 cumulative effect Effects 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 238000004088 simulation Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 238000009435 building construction Methods 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 230000005484 gravity Effects 0.000 description 1
- 238000007689 inspection Methods 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- NJPPVKZQTLUDBO-UHFFFAOYSA-N novaluron Chemical compound C1=C(Cl)C(OC(F)(F)C(OC(F)(F)F)F)=CC=C1NC(=O)NC(=O)C1=C(F)C=CC=C1F NJPPVKZQTLUDBO-UHFFFAOYSA-N 0.000 description 1
- 230000002093 peripheral effect Effects 0.000 description 1
- 230000003068 static effect Effects 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
Images
Classifications
-
- E—FIXED CONSTRUCTIONS
- E04—BUILDING
- E04B—GENERAL BUILDING CONSTRUCTIONS; WALLS, e.g. PARTITIONS; ROOFS; FLOORS; CEILINGS; INSULATION OR OTHER PROTECTION OF BUILDINGS
- E04B1/00—Constructions in general; Structures which are not restricted either to walls, e.g. partitions, or floors or ceilings or roofs
- E04B1/35—Extraordinary methods of construction, e.g. lift-slab, jack-block
- E04B1/3511—Lift-slab; characterised by a purely vertical lifting of floors or roofs or parts thereof
-
- E—FIXED CONSTRUCTIONS
- E04—BUILDING
- E04B—GENERAL BUILDING CONSTRUCTIONS; WALLS, e.g. PARTITIONS; ROOFS; FLOORS; CEILINGS; INSULATION OR OTHER PROTECTION OF BUILDINGS
- E04B1/00—Constructions in general; Structures which are not restricted either to walls, e.g. partitions, or floors or ceilings or roofs
- E04B1/342—Structures covering a large free area, whether open-sided or not, e.g. hangars, halls
-
- E—FIXED CONSTRUCTIONS
- E04—BUILDING
- E04B—GENERAL BUILDING CONSTRUCTIONS; WALLS, e.g. PARTITIONS; ROOFS; FLOORS; CEILINGS; INSULATION OR OTHER PROTECTION OF BUILDINGS
- E04B1/00—Constructions in general; Structures which are not restricted either to walls, e.g. partitions, or floors or ceilings or roofs
- E04B1/35—Extraordinary methods of construction, e.g. lift-slab, jack-block
- E04B2001/3588—Extraordinary methods of construction, e.g. lift-slab, jack-block using special lifting or handling devices, e.g. gantries, overhead conveying rails
Abstract
The invention provides a construction method for jacking a large-span steel net rack in a high altitude with an integral variable angle, which is used for solving the problem of jacking a steel net rack with a larger gradient. The jacking construction method adopts a step-by-step jacking mode, firstly all jacking points are synchronously jacked after ground assembly, after jacking is carried out to a set lowest finished elevation, each jacking point is asynchronously jacked (at different speeds) to the finished elevation according to the height of each point, and the whole steel net rack is in an inclined state relative to the horizontal plane, so that the problem that jacking cannot be carried out simultaneously according to different speeds is solved, and the method of the same time, multiplied by different speeds and = different jacking heights is adopted to realize the installation of the large-angle inclined steel net rack. The construction period is saved by adopting step-by-step jacking, the workload and the cost of the full-frame are reduced, and the welding and assembling quality is guaranteed; the method is most convenient and has the minimum construction workload.
Description
Technical Field
The invention relates to a jacking construction method, in particular to a large-span steel truss high-altitude integral variable-angle jacking construction method, and belongs to the technical field of building construction.
Background
Along with the construction of large stadiums, theaters and cultural and sports centers in various regions, various large-span steel structure net racks are increasingly applied to building roofs. Steel structural wire frames for such projects are typically large in span, large in volume, and high in height.
The traditional net rack mounting and constructing methods at present comprise a high-altitude assembling method, an integral lifting method and a jacking method. The high-altitude assembly method needs to consume a large amount of frame materials to set up an operation platform, and has high material lease and labor cost; the integral lifting method has the characteristics of simple and convenient construction, short construction period, easy guarantee of engineering quality and the like, but needs to guarantee reliable connection between the lifting frame and the structure body, is restricted by the site environment and is not easy to construct. The jacking method integrates the advantages, the net rack is assembled on the ground, safety and time saving are realized, the assembling quality is convenient to guarantee, and the installation of the jacking frame body is not limited by the field and the surrounding environment, so that the jacking method is generally applied to the construction of the net rack structure with balanced weight.
For an inclined steel net rack with a slope and a height difference, patent document No. CN 110792265A provides an integral synchronous jacking method for a large-span combined type overweight eccentric slope angle steel structure, but the height difference of an initial section of a jacking frame is adapted to the slope difference of the combined steel structure, and the combined jacking frame is adopted to realize the integral synchronous jacking of the combined steel structure. The integral synchronous jacking method can only be suitable for the inclined steel net rack with small height difference, for example, the difference of two side slopes mentioned in the background technology of the document is 1.8 meters; to the steel mesh frame that has great slope, steel mesh frame both sides difference in height if adopt this kind of mode easily to lead to the focus skew for jacking in-process steel mesh frame unstability, the potential safety hazard is big.
Therefore, for a steel net rack with a larger gradient (such as a steel net rack of an athletic field, the steel net rack has a height with 22.5 meters at the highest point, 13.0 meters at the lowest point, a height difference of 9.5 meters, and a projected area of about 8831m 2 ) The high-altitude splicing is difficult to be scattered due to span and gradient factors, and the welding quality is difficult to be ensured; the integral lifting method needs to prevent lateral displacement in the process of inclined jacking, so that the potential safety hazard is large; the traditional jacking method easily causes gravity center shift, so that the steel net rack is unstable in the jacking process and has great potential safety hazard; the traditional jacking method is not suitable, and a new jacking method needs to be designed according to the characteristics and the field situation of the project.
Disclosure of Invention
In view of the above, the invention provides a large-span steel net rack high-altitude integral variable-angle jacking construction method, which adopts a step-by-step jacking mode and can perform jacking and installation work of a steel net rack with long structural span, heavy net rack weight and large gradient.
The technical scheme adopted by the invention is as follows: the construction method for the large-span steel truss high-altitude integral variable-angle jacking comprises the following steps: the method comprises the following steps:
s1: jacking devices which correspond to the jacking points on the steel net frame one by one are arranged on the terrace;
s2: assembling the steel net rack on the ground, and connecting each jacking point on the steel net rack with a jacking frame of a jacking device at a corresponding position respectively after the assembly of the steel net rack is completed;
s3: synchronous jacking
Adjusting the initial heights of all the jacking frames to be the same, and synchronously jacking all the jacking points to the position where the steel net rack is connected with the lowest support by using the jacking frames; the synchronous jacking fingers have the same jacking speed;
then stopping synchronous jacking, extending the steel net rack to the lowest support, and performing rod supplementing operation to movably connect the lowest support;
s4: asynchronous jacking
Resetting the jacking speed of the jacking frame at each jacking point according to the height difference between each jacking point and the lowest support and the set asynchronous jacking time, and jacking each jacking point at different speeds to enable the whole steel mesh frame to be jacked at a gradually inclined variable angle; until the steel net rack is jacked to the position connected with the highest support;
s5: extending the steel net rack to each support, and performing rod supplementing operation to fixedly connect each support; meanwhile, fixedly connecting the net rack rod piece at the lowest support with the lowest support; and then falling back and dismantling the jacking device.
As a preferred aspect of the present invention, when there is an overhanging platform or a landing platform within the jacking range of the steel net rack, in step S2: when carrying out the assembly of steel net rack on ground, do not assemble earlier the jacking in-process can with encorbelment the platform or the net rack member that the platform took place to interfere falls to the ground treats steel net rack jacking surpasses the platform of encorbelmenting or after falling to the ground the platform, carry out the piece together that looses of corresponding position net rack member again.
As a preferred embodiment of the present invention, in step S4: when the net rack lower chord ball of the steel net rack at the jacking point is opposite to the transverse displacement amount generated by the jacking ball support of the jacking frame exceeds a set value, the position of the jacking frame is adjusted according to the transverse displacement amount, and the transverse position adjustment amount of the jacking frame is consistent with the transverse displacement amount.
As a preferred aspect of the present invention, when the position of the jack-up frame is adjusted, the position of the jack-up frame is adjusted one at a time.
As a preferred mode of the invention, the net rack ball connected with the lowest support on the steel net rack is a support ball, and the top of the lowest support is provided with a semi-spherical groove used for matching with the support ball;
one side of the lowest support, which faces the highest support, is the front side of the lowest support, and the opposite side of the lowest support is the rear side;
in step S3: placing the support ball in a hemispherical groove at the top of the lowest support; the support ball can rotate in the hemispherical groove during asynchronous jacking;
a baffle is arranged at the rear side of the lowest support and used for preventing the lowest support from bending and deforming in the asynchronous jacking process;
and after the asynchronous jacking is finished, welding and fixing the support ball and the lowest support.
As a preferable mode of the present invention, one side of the lowest support facing the highest support is a front side thereof, and the opposite side is a rear side;
in step S3: the rear side of the lowest support is provided with a support ball supporting structure, which comprises: a stay bar and a wire rope;
one end of the stay bar props against the support ball, and the other end of the stay bar extends obliquely backwards and then is fixed with the structural column; one end of the steel wire rope is connected with the lowest support, and the other end of the steel wire rope is connected with the support rod.
As a preferred aspect of the present invention, when the position of the lifting frame is adjusted:
unloading a jacking hydraulic oil cylinder of the jacking device, and lowering the jacking frame to a set position below a lower chord ball of the net rack at the jacking point; then separating the supporting legs of the jacking frame connected with the steel plate on the ground from the steel plate, jacking the jacking frame by using a jack in the displacement direction to enable the jacking frame to move, wherein the movement amount is equal to the transverse displacement amount of the lower chord ball of the net rack at the jacking point; then the supporting legs of the jacking frame are fixed again, and the jacking device is jacked back to the original position.
As a preferred mode of the invention, a sliding rail is arranged on the steel plate, and the supporting leg of the jacking frame is in sliding fit with the steel plate; and when the displacement for pushing the jacking frame to slide along the slide rail is equal to the transverse displacement of the net rack lower chord ball at the jacking point, locking the position of the jacking frame.
As a preferred embodiment of the present invention, in step S3: when the lifting frame is lifted to a set height position, inclined support rods are additionally arranged on two opposite sides of more than one group of lifting frames to serve as rigid supports;
in step S4: and when the lifting frame is lifted to a set height position, the two opposite sides of one group of the lifting frame are additionally provided with the guy cables for supporting.
As a preferred mode of the invention, the steel net rack is of a semicircular structure and comprises an arc-shaped section and a straight line section;
in step S1, 24 jacking points are provided on the steel net rack; wherein 12 jacking points are located straightway and even interval distribution of steel net rack, and all the other jacking points are located the segmental arc and along circumference interval distribution.
Has the beneficial effects that:
(1) the invention provides an integral variable-angle jacking construction method for a large-span steel net rack, which adopts a step-by-step jacking mode, and comprises the steps of jacking all jacking points synchronously after ground assembly, jacking to a set lowest finished elevation, jacking each jacking point to the finished elevation asynchronously (at different rates) according to the height of each point, and enabling the integral steel net rack to be in an inclined state relative to a horizontal plane, so that the problem that jacking cannot be carried out simultaneously according to different rates is solved, and the installation of the large-angle inclined steel net rack is realized by adopting a method of the same time multiplied by different rates = different jacking heights. The construction period is saved by adopting step-by-step jacking, the workload and the cost of the full-frame are reduced, and the welding and assembling quality is guaranteed; the method is most convenient and has the minimum construction workload.
(2) When there is the platform of encorbelmenting in the jacking within range, adopt ground to assemble, treat that the steel mesh frame crosses this platform or support after, the mode of piecing together in pieces of carrying out corresponding position rack member, solve the jacking within range and have the secondary jacking problem behind the platform of encorbelmenting.
(3) Because become angle jacking (asynchronous jacking) in-process, can make jacking point department steel net rack lower chord ball produce lateral displacement for the jacking ball support of jacking cylinder, based on this, in asynchronous jacking in-process, carry out lateral adjustment to each jacking frame respectively, make its lateral displacement that can adapt to jacking point department steel net rack lower chord ball, guarantee the reliable jacking to the steel mesh frame.
(4) After synchronous jacking, only arrange the support ball of member tip in the hemisphere inslot at support A top, earlier not weld with vertical gusset to when steel mesh frame slope adjustment (asynchronous jacking promptly), the support ball can be at hemisphere inslot rotation, guarantees that this node does not disturb going on smoothly of asynchronous jacking.
(5) When the position of the jacking frame is adjusted, the position of only one jacking frame is adjusted at a time, so that the construction safety is ensured.
(6) Before asynchronous jacking, set up the baffle at the rear side of minimum support, can prevent that the minimum support bending deformation of asynchronous jacking in-process.
(7) Before asynchronous jacking, set up support ball bearing structure in the rear side of minimum support, minimum support bending deformation when can preventing the steel mesh frame slope adjustment.
(8) In order to conveniently adjust the position of the jacking frame and accurately adjust the displacement, the supporting legs of the jacking frame are in sliding fit with the steel plate; when the displacement for pushing the jacking frame to slide along the slide rail is equal to the transverse displacement of the net rack lower chord ball at the jacking point, the position of the jacking frame is locked.
Drawings
FIG. 1 is a schematic view of the arrangement of steel net frames and jacking points thereon in an athletic stadium;
FIG. 2 is a schematic diagram of an initial stage of synchronous jacking;
FIG. 3 is a schematic diagram of a case where a diagonal brace is added after synchronous jacking to a certain height;
FIG. 4 is a schematic view of the steel truss extending toward the support A;
FIG. 5 is a schematic view of a pedestal support;
FIG. 6 is a schematic diagram of the amount of offset after the jacking point is changed in angle;
FIG. 7 is a schematic diagram showing the positions of the jacking ball support and the net rack lower chord ball during jacking synchronous jacking and asynchronous jacking;
FIG. 8 is a schematic diagram of the movement of the jacking frame;
FIG. 9 is a schematic diagram of asynchronous jacking into position;
FIG. 10 is a schematic diagram of a steel truss jacking drawknot;
fig. 11 is a schematic diagram of arrangement of monitoring points in the steel framework jacking process.
Wherein: the system comprises a steel net rack 1, a jacking device 2, a cantilever platform 3, a chain hoist 4, an inclined support rod 5, a support A6, a baffle 7, a vertical rib plate 8, a support ball 9, a support ball 10, a support rod 11, a steel wire rope 12, a jacking ball support 13, a net rack lower chord ball 14, a jacking frame 15, a jack 16, a cable wind rope 17, a tie rope 18, a structural column 19 and a monitoring point 19.
Detailed Description
The invention is described in further detail below with reference to the figures and examples.
As shown in fig. 1, a steel net rack 1 of a certain stadium is of a semicircular structure and comprises an arc-shaped section and a straight line section; the height of the steel mesh frame 1 is 22.5 meters (the end of the right arc section), 13.0 meters (the end of the left straight line section) of the highest point, 9.5 meters of height difference, the supporting form is upper chord peripheral column point supporting (namely the supporting seat is connected with a net frame upper chord ball, the net frame upper chord ball connected with the supporting seat is a support ball 9), a plurality of supports (the supports are fixed on a structural column 18) are respectively arranged along the circumferential direction and the straight line of the arc section of the steel mesh frame 1 to support the steel mesh frame, the height of the highest support is 22.5 meters, and the height of the lowest support is 13.0 meters; projection area is about 8831m 2 (ii) a Amounting to about 600 more tons.
For realizing the safe and reliable installation of this track and field hall steel net rack 1, this embodiment provides a whole variable angle jacking construction method of large-span steel net rack high altitude, adopt the mode of substep jacking, at first all jacking points are synchronous (the same speed) jacking after the ground is assembled, after the jacking is to the minimum completion elevation of settlement (the position that steel net rack 1 and minimum support are connected), each jacking point is according to the asynchronous jacking (different speeds) of each point height to accomplishing the elevation, whole steel net rack 1 is the tilt state for the level this moment.
The following describes each step in the construction method in detail.
The method comprises the following steps: installation jacking device
The jacking device 2 is installed at a set position on the terrace, and the foundation of the jacking device 2 has enough strength.
In this example, the steel net rack 1 of the stadium is provided with 24 jacking points (as shown in fig. 1 as D1-D24), and each jacking point corresponds to one set of jacking device 2 for jacking the jacking point. The 24 jacking points are respectively jacking points D1-D12 which are uniformly distributed along the radial direction of the straight-line segment at intervals and jacking points D13-D24 which are distributed along the circumferential direction of the arc-shaped segment at intervals.
Wherein jacking device 2 can adopt the steel construction rack jacking device disclosed in patent CN207079729U, include: a hydraulic ram and jacking frame 14; the hydraulic oil cylinder is supplied with oil by an external hydraulic station and is connected with a jacking point (a jacking ball support at the top of the jacking oil cylinder is connected with a net rack lower chord ball) and used for jacking corresponding to the jacking point; the jacking frame 14 is used for moving the hydraulic oil cylinder upwards. The jacking frame 14 comprises an upper bracket, a multi-stage standard knot and a lower bracket which are coaxially arranged from top to bottom in sequence.
Step two: steel net rack assembly
The steel net rack 1 is welded and assembled on the ground, and because the steel net rack 1 is an inclined plane net rack in the embodiment, the gradient is 7 degrees, the height difference between two ends is 9.5m, the steel net rack is selected to be horizontally placed for ground plane assembly, and then jacking is carried out.
The assembly of the steel net rack 1 is completed on the ground, so that the quality of welding seams is convenient to ensure, the quality inspection such as welding seam detection, net rack rod piece installation position check and the like is convenient, the installation quality of a combined steel structure is convenient to ensure, the vertical transportation and hoisting operation can be reduced, and the potential safety hazard of high-place operation is avoided; the combined steel structure is assembled on the ground, so that the jacking frame is convenient to install, the construction efficiency is high, and the construction quality is easy to guarantee.
In this example, as shown in fig. 2, a cantilevered platform 3 with 2m is provided at the left side (lower end) within the jacking range of the steel net rack 1 (i.e. after the steel net rack 1 is jacked in place, the cantilevered platform 3 is located below the steel net rack 1); the bottom of the right side (high end) is provided with a landing platform with a set height; based on this, when the welding assembly of the steel net rack 1 is carried out on the ground, firstly, the net rack rod pieces which can interfere with the platform (including the overhanging platform 3 and the landing platform) in the jacking process of the end where the platform is located are not assembled, so that the steel net rack 1 does not interfere with the platform when passing through the platform; after the steel net frame 1 passes over the platform, the net frame rod pieces at the corresponding positions are assembled in a scattered way.
After the steel net rack 1 is assembled, all jacking points on the steel net rack 1 are respectively connected with the jacking devices 2 at corresponding positions on the ground. In addition, for guaranteeing the safety of steel net rack 1 jacking process, it has two chain calabashes 4 to draw to one side at the lower extreme of steel net rack 1, and the one end of two chain calabashes 4 links to each other with the both ends of steel net rack 1 bottom respectively, and the other end alternately draws to ground and subaerial tie point reliable connection to one side.
Step three: jacking up
Jacking is carried out twice, wherein the first jacking is flat top (namely synchronous jacking), and the second jacking is inclined top (namely asynchronous jacking); after the first jacking is finished, the net rack rod pieces connected with the supports at the lower end of the left side are firstly assembled in a scattered mode, and then the inclined jacking is carried out after the net rack rod pieces are assembled; and after the pitched roof is in place, the net rack rod pieces connected with the support at the right side high position are scattered, and after the scattered transmission, the net rack is unloaded to complete the installation of the net rack.
The following steps are described in detail:
301: synchronous jacking
Initially, adjusting the bottom elevations of all the jacking devices 2 to be the same, adjusting the jacking displacements of all the jacking points to be synchronous, and determining jacking parameters to meet the requirement that the form and position errors of the combined steel structure are within an allowable range; in the initial jacking stage, the steel net rack 1 is jacked to the position 200mm for the first time by using the jacking device 2, as shown in fig. 2, at the moment, static load is carried out for 30 minutes, the conditions of each net rack rod piece and weld craters in the steel net rack 1 are checked, and if the net rack rod piece is bent or the weld craters are cracked, the treatment is stopped in time; and meanwhile, measurement and observation are carried out, the downwarping, displacement and elevation deviation of the net rack are recorded in time, and the overlarge deviation is found and adjusted in time. Therefore, the uniform stress of each net rack rod piece in the steel net rack 1 is ensured, and the welding seam meets the requirement. In the early stage of synchronous jacking, the height of the steel net rack 1 is checked every time the steel net rack is jacked for 200 mm; in the later stage of synchronous jacking, the height of the steel net rack 1 is checked every 500mm, so that each jacking point of the steel net rack 1 is ensured to rise synchronously until the steel net rack is synchronously jacked to a set height position.
In the embodiment, because 24 jacking points are uniformly distributed, the jacking force difference of each jacking point is less, and the stress state is optimal during jacking. In order to ensure the stability of the jacking process, the maximum deviation of the jacking asynchronous value is controlled to be 2 cm.
In the synchronous jacking process, when the steel net frame 1 is jacked for one set standard height, a standard section of a jacking frame 14 is additionally arranged; when the lifting frame is lifted to a set height, the inclined supporting rod 5 is added to the lifting frame 14 to be used as a rigid support so as to ensure the stability of the lifting frame. As shown in fig. 3, in this example, when the steel net rack 1 is jacked to more than 6 meters, the diagonal braces 5 are installed on at least four sets of jacking frames 14, and one diagonal brace 5 is installed on each of two opposite sides of the jacking frame 14. After the steel net rack 1 is synchronously jacked to a set height (lowest finished elevation), the net rack rod pieces connected with the support at the lower end of the left side are scattered and spliced. Specifically, the method comprises the following steps:
as shown in fig. 4 and 5, when the steel net rack 1 is lifted to the lowest finished elevation, the synchronous lifting work is stopped, the steel net rack is extended to the support at the lowest finished elevation, namely the lowest support (the support is A6, and the lower support is provided with a plurality of supports, namely a plurality of supports A6), and the rod supplementing operation is carried out to connect the supports A6; meanwhile, a reliable baffle 7 is arranged at the rear side (namely, the left side, which is the side opposite to the arc-shaped section of the steel net rack 1 on the support A6) of the support A6, so that the support A6 is prevented from bending and deforming when the gradient of the steel net rack 1 is adjusted.
The connection mode of the support A6 and the steel net rack 1 is as follows: the top of the seat A6 is provided with a semi-spherical groove for matching with the seat ball 9; the connection between the support A6 and the steel net rack 1 is realized through the matching of the support ball 9 and the vertical rib plate 8 on the support A6.
At this stage, only the support ball 9 at the end of the net rack rod piece is arranged in the hemispherical groove at the top of the support A6 and is not welded with the vertical rib plate 8, so that when the gradient of the steel net rack 1 is adjusted, the support ball 9 can rotate in the hemispherical groove, and the support ball 9 and the vertical rib plate 8 are welded after the gradient of the steel net rack 1 is adjusted.
When the steel net rack extends to the support A6, the installation method of the steel net rack is as follows: firstly, the support A6 is flattened and padded, the support ball 9 must naturally enter the hemispherical groove at the top of the support A6, and the net rack rod piece connected with the support ball 9 is ensured not to generate extra stress, so that the stress state is changed. After all the support balls 9 are in place, the support balls 9 are supported, and the support balls 9 are prevented from moving laterally in the inclined jacking process. As shown in fig. 5, one end of the stay bar 10 is abutted against the support ball 9, the other end of the stay bar extends obliquely backwards and then is fixed by four M20 expansion bolts, and then one end of the steel wire rope 11 is connected with the support A6, and the other end of the steel wire rope is connected with the stay bar 10.
302: asynchronous jacking
As shown in fig. 6, the asynchronous jacking process is a process of changing the angle of the whole steel truss 1 in a high altitude mode, and because each jacking point has a height difference with the lowest support on the left side, the height difference needs to be reserved before jacking is finished, and the height differences at the jacking points are different and need to be set respectively; based on the method, the jacking oil cylinder is controlled by adopting a numerical control technology, and the jacking speed of each jacking point is reset according to the height difference between each jacking point and the lowest support (the height difference is the height required for jacking each jacking point in the asynchronous jacking process) and the set asynchronous jacking time, so that the steel net rack 1 is jacked in a gradually inclined variable angle mode. The asynchronous jacking is to gradually lift and incline by taking the lowest support as the center until the steel net rack 1 is connected with the highest support, as shown in fig. 9.
In the asynchronous jacking process, the verticality of the jacking frame 14 needs to be adjusted, and the steel net rack 1 cannot move horizontally when being jacked horizontally (synchronously jacked); but when the slope type jacking (asynchronous), the jacking point of the high end of the steel net rack 1 can be horizontally displaced towards the low end: based on this, the verticality of the jacking frame 14 needs to be adjusted; through calculation, 750mm is completed by jacking at the rightmost side, the lateral displacement deviation exceeds 33mm, the verticality of the jacking frame 14 is required to be adjusted, and meanwhile, the tilting and sliding distance of the steel net rack 1 is controlled by retracting and releasing the chain block 4. Specifically, the method comprises the following steps:
in the variable-angle jacking process, the net rack lower chord ball 13 of the steel net rack 1 at the jacking point can generate lateral displacement leftwards relative to the jacking ball support 12 of the jacking oil cylinder; therefore, as shown in fig. 7, the matching of the jacking ball support 12 of the jacking oil cylinder and the net rack lower chord ball 13 is divided into two states, when the jacking is synchronous, the net rack lower chord ball 13 does not have the transverse relative displacement relative to the jacking ball support 12, and when the jacking is asynchronous, the net rack lower chord ball 13 has the transverse relative displacement relative to the jacking ball support 12.
When the leftward movement size of the net rack lower chord ball 13 exceeds 33mm, the horizontal position of the jacking frame 14 is adjusted; meanwhile, supporting facilities (such as guy cables 16) are further arranged on the jacking frame 14 along with the jacking height, and the overall displacement trend of the steel net rack 1 caused by the inclination angle is controlled. Specifically, the method comprises the following steps:
the asynchronous jacking of the steel grid structure 1 is started after the steel grid structure is in place at the lowest support, and the jacking speed of each jacking point is reset according to the height difference from each jacking point to the lowest support every time the highest point is jacked once (750 mm), so that the steel grid structure 1 gradually presents an inclined state. And moving the jacking frame 14 once when the left movement size exceeds 33mm according to the calculated left movement size of the net rack lower chord ball 13 at the corresponding position after each jacking of each vertex until the steel net rack 1 is jacked to the joint of the highest support.
In the jacking process, when the jacking frame 14 reaches a set height (for example, fifteen meters), the cable rope 16 is additionally pulled at the reliable connection position of the ground to ensure the stability of the cable rope, the cable rope 16 adopts a phi 16 steel wire rope and a hand-pulled chain block, and two ends of the cable rope are respectively fixed on the jacking frame 14 and the ground and are reliably connected with the ground (a column foot or an anchor bolt is generally adopted according to the field condition).
Each jacking frame 14 needs to move transversely according to the displacement of the net rack lower chord ball 13 at the corresponding jacking point, but the movement of each jacking frame 14 cannot be performed simultaneously, and one jacking frame is needed. Taking jacking points D1-D12 as an example, firstly unloading a jacking hydraulic oil cylinder of the jacking device 2 corresponding to the jacking point D2, lowering the jacking frame 14 to a position 2cm below the net rack lower chord ball 13, and continuously protecting the net rack lower chord ball 13; then slightly loosening the wind-catching rope 16 at the position with the height of fifteen meters, so that the wind-catching rope not only keeps the restraint on the jacking frame 14, but also can have a certain displacement; then separating the supporting legs of the jacking frame connected with the steel plate on the ground from the steel plate, removing the rigid support at the position of 6m (namely the inclined stay bar 5 at the position), and jacking the jacking frame 14 in the displacement direction by using two jacks 15 to enable the jacking frame to move, wherein the movement amount is equal to the displacement amount of the net rack lower chord ball 13 at the jacking point; and then, the supporting legs of the jacking frame are fixed again, the rigid support is fixed again, the cable rope 16 is tensioned and the rigid support is corrected, after all the supporting legs are intact, the jacking device 2 corresponding to the jacking point D2 is jacked back to the original position, and after all the supporting legs are completely jacked, the next jacking point is moved.
The steel plate can be provided with a slide rail, so that the supporting legs of the jacking frame are in sliding fit with the steel plate, and when the displacement of the jacking frame 14 pushed by the jack 15 to slide along the slide rail is equal to the displacement of the lower chord ball 13 of the jacking point net rack, the jacking frame 14 is locked in position.
The horizontal displacement distance of the jacking frame 14 is the size of the jacking point which is shifted to the left when the jacking point is jacked each time according to the horizontal shift distance of the corresponding jacking point and the simulation calculation of the variable-angle shift diagram.
In this example, the cumulative lift size table of the jacking point and the leftward offset size table of the jacking point are obtained by simulation and are respectively:
(a) every time the jacking point jacks, the jacking point shifts the size table to the left
| Number of lifts | N1 left shift (mm) | N2 left shift (mm) | N3 left shift (mm) | N4 left shift (mm) | N5 left shift (mm) | N6 left shift (mm) |
| 1 | 44 | 43 | 42 | 41 | 48 | 40 |
| 2 | 87 | 83 | 80 | 76 | 81 | 72 |
| 3 | 128 | 120 | 113 | 105 | 105 | 95 |
| 4 | 169 | 155 | 141 | 128 | 122 | 111 |
| 5 | 208 | 187 | 166 | 144 | 130 | 117 |
| 6 | 247 | 216 | 185 | 155 | 132 | 116 |
| 7 | 284 | 242 | 201 | 159 | 125 | 107 |
| 8 | 321 | 266 | 211 | 157 | 110 | 88 |
| 9 | 356 | 287 | 218 | 149 | 87 | 62 |
| 10 | 390 | 305 | 220 | 134 | 57 | 28 |
| 11 | 424 | 320 | 217 | 114 | 18 | -15 |
| 12 | 437 | 326 | 215 | 103 | 0 | -35 |
(b) When the jacking point jacks each time, the cumulative lifting size table of the jacking point:
| number of lifts | N1(mm) | N2(mm) | N3(mm) | N4(mm) | N5(mm) | N6(mm) |
| 1 | 93 | 248 | 402 | 557 | 711 | 750 |
| 2 | 186 | 495 | 805 | 1114 | 1423 | 1500 |
| 3 | 280 | 744 | 1207 | 1671 | 2134 | 2250 |
| 4 | 374 | 992 | 1610 | 2228 | 2846 | 3000 |
| 5 | 469 | 1241 | 2013 | 2785 | 3557 | 3750 |
| 6 | 564 | 1490 | 2416 | 3342 | 4268 | 4500 |
| 7 | 659 | 1740 | 2820 | 3900 | 4980 | 5250 |
| 8 | 755 | 1989 | 3223 | 4457 | 5691 | 6000 |
| 9 | 852 | 2240 | 3627 | 5015 | 6403 | 6750 |
| 10 | 949 | 2490 | 4032 | 5573 | 7115 | 7500 |
| 11 | 1046 | 2741 | 4436 | 6131 | 7826 | 8250 |
| 12 | 1086 | 2845 | 4604 | 6363 | 8122 | 8562 |
Wherein: n1 represents jacking points D1-D12, N2 represents jacking points D13 and D24, N3 represents jacking points D14 and D23, N4 represents jacking points D15 and D22, N5 represents jacking points D16 and D21, N6 represents jacking points D17-D20, 750mm jacking of the rightmost N6 is performed each time, 562mm jacking is performed the last time, and the horizontal displacement of the N1 point is the largest, so that the N1 point is used as a base point, the jacking is stopped after the N1 point is accumulated to 20mm, and the jacking frame 14 is moved.
After the asynchronous jacking of the steel net rack 1 is finished, the steel net rack 1 is of an inclined structure as shown in fig. 9, and at the moment, the steel net rack 1 is assembled and installed to be connected with each support; after the completion of the splicing installation, the steel net frame 1 is integrally spliced and accepted, after the acceptance is qualified, the jacking frame 14 is integrally fallen back, the steel net frame 1 is fallen and placed on the support of the permanent structural column 18 to be in place, and is welded, the jacking frame 14 is detached, and the construction of the steel net frame 1 is completed.
As shown in fig. 10, in order to ensure the safe operation of the whole jacking process of the steel net rack 1, the lower chord ball part of the net rack at the right end of the steel net rack 1 is tied with the structural column 18 through a tie rope 17 (adopting a steel wire rope), each support is provided with a tie point, 6 tie points are arranged, and due to the displacement in the jacking process, the tie rope 17 is provided with proper tightness and is adjusted in time according to the jacking amount, the tie rope 17 is hung with a chain block, each chain block is a 5-ton chain block, after each jacking, the proper length is discharged, so that the tie rope 17 is always in a slack state. The method specifically comprises the following steps: according to the support counter force calculation under the self-weight state of the steel net rack 1, six tie ropes 17 are added, and the lateral displacement of the steel net rack 1 is controlled by matching with the chain block 4. Meanwhile, the baffle 7 on the left side of the support A6 plays a role of safety, and is basically not stressed or is slightly stressed in the jacking process.
In addition, at the asynchronous jacking in-process of steel truss 1, detect with spirit level and total powerstation, it is specific: the method comprises the steps of simultaneously carrying out recording and measuring of positioning points by using a level meter and a total station, checking and comparing in time, checking whether the steel net rack 1 has abnormal change due to the change of internal force caused by asynchronous jacking, recording in time, stopping jacking immediately if the abnormal change occurs, finding out the change reason, and continuing jacking after adjustment to avoid danger. The level meter is monitored by adopting a lower hanging ruler method, the total station is monitored by utilizing a reflective sticker, and monitoring points 19 are arranged as shown in fig. 11; one monitoring point 19 is arranged at each jacking point position, and three monitoring points 19 are arranged in the middle of the steel net rack 1.
The foregoing is a more detailed description of the present invention that is presented in conjunction with specific embodiments, and the practice of the invention is not to be considered limited to those descriptions. For those skilled in the art to which the invention pertains, several simple deductions or substitutions can be made without departing from the spirit of the invention, and all shall be considered as belonging to the protection scope of the invention.
Claims (7)
1. The large-span steel truss elevated integral variable-angle jacking construction method is characterized by comprising the following steps of: the method comprises the following steps:
s1: jacking devices which correspond to the jacking points on the steel net frame one by one are arranged on the terrace;
s2: assembling the steel net rack on the ground, and after the assembling of the steel net rack is completed, connecting each jacking point on the steel net rack with a jacking frame of a jacking device at a corresponding position respectively;
s3: synchronous jacking
Adjusting the initial heights of all the jacking frames to be the same, and synchronously jacking all the jacking points to the position where the steel net rack is connected with the lowest support by using the jacking frames; the synchronous jacking fingers have the same jacking speed;
then stopping synchronous jacking, extending the steel net rack to the lowest support, and performing rod supplementing operation to movably connect the lowest support;
s4: asynchronous jacking
Resetting the jacking speed of the jacking frame at each jacking point according to the height difference between each jacking point and the lowest support and the set asynchronous jacking time, and jacking each jacking point at different speeds to enable the whole steel mesh frame to be jacked at a gradually inclined variable angle; until the steel net rack is jacked to the position connected with the highest support;
s5: extending the steel net rack to each support, and performing rod supplementing operation to fixedly connect each support; meanwhile, fixedly connecting the net rack rod piece at the lowest support with the lowest support; then falling back and dismantling the jacking device;
in step S4: when the transverse displacement generated by the net rack lower chord ball of the steel net rack at the jacking point relative to the jacking ball support of the jacking frame exceeds a set value, adjusting the position of the jacking frame according to the transverse displacement, wherein the transverse position adjustment amount of the jacking frame is consistent with the transverse displacement;
when adjusting the position of jacking frame:
unloading a jacking hydraulic oil cylinder of the jacking device, and lowering the jacking frame to a set position below a lower chord ball of the net rack at the jacking point; then separating the supporting legs of the jacking frame connected with the steel plate on the ground from the steel plate, jacking the jacking frame by using a jack in the displacement direction to enable the jacking frame to move, wherein the movement amount is equal to the transverse displacement amount of the lower chord ball of the net rack at the jacking point; then fixing the supporting legs of the jacking frame again, and jacking the jacking device to the original position;
the steel plate is provided with a slide rail, and the supporting leg of the jacking frame is in sliding fit with the steel plate; and when the displacement for pushing the jacking frame to slide along the slide rail is equal to the transverse displacement of the net rack lower chord ball at the jacking point, locking the position of the jacking frame.
2. The large-span steel framework elevated whole variable-angle jacking construction method according to claim 1, characterized in that: when the jacking range of the steel net rack has an overhanging platform or a landing platform, in step S2: when carrying out the assembly of steel net rack on ground, do not assemble earlier the jacking in-process can with encorbelment the platform or the net rack member that the platform took place to interfere falls to the ground treats steel net rack jacking surpasses the platform of encorbelmenting or after falling to the ground the platform, carry out the piece together that looses of corresponding position net rack member again.
3. The large-span steel framework elevated air integral variable-angle jacking construction method of claim 1, wherein the construction method comprises the following steps: when the position of the jacking frame is adjusted, the position of the jacking frame is adjusted one time.
4. The large-span steel framework elevated air integral variable-angle jacking construction method of claim 1, wherein the construction method comprises the following steps: a net rack ball connected with the lowest support on the steel net rack is a support ball, and the top of the lowest support is provided with a semi-spherical groove matched with the support ball;
one side of the lowest support, which faces the highest support, is the front side of the lowest support, and the opposite side of the lowest support is the rear side;
in step S3: placing the support ball in a hemispherical groove at the top of the lowest support; the support ball can rotate in the hemispherical groove in the asynchronous jacking process;
a baffle is arranged at the rear side of the lowest support and used for preventing the lowest support from bending and deforming in the asynchronous jacking process;
and after the asynchronous jacking is finished, welding and fixing the support ball and the lowest support.
5. The large-span steel framework elevated integral variable-angle jacking construction method according to any one of claims 1 to 4, characterized in that: one side of the lowest support, which faces the highest support, is the front side of the lowest support, and the opposite side of the lowest support is the rear side;
in step S3: the rear side of the lowest support is provided with a support ball supporting structure, which comprises: a stay and a wire rope;
one end of the support rod props against the support ball, and the other end of the support rod extends obliquely backwards and then is fixed with the structural column; one end of the steel wire rope is connected with the lowest support, and the other end of the steel wire rope is connected with the support rod.
6. The large-span steel framework elevated integral variable-angle jacking construction method according to any one of claims 1 to 4, characterized in that: in step S3: when the lifting frame is lifted to a set height position, inclined support rods are additionally arranged on two opposite sides of more than one group of lifting frames to serve as rigid supports;
in step S4: and when the lifting frame is lifted to a set height position, the two opposite sides of one group of the lifting frame are additionally provided with the guy cables for supporting.
7. The large-span steel framework elevated integral variable-angle jacking construction method according to any one of claims 1 to 4, characterized in that: the steel net rack is of a semicircular structure and comprises an arc-shaped section and a straight line section;
in step S1: 24 jacking points are arranged on the steel net rack; wherein 12 jacking points are located straightway and even interval distribution of steel net rack, and all the other jacking points are located the segmental arc and along circumference interval distribution.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210720064.3A CN114809310B (en) | 2022-06-24 | 2022-06-24 | Large-span steel truss high-altitude integral variable-angle jacking construction method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210720064.3A CN114809310B (en) | 2022-06-24 | 2022-06-24 | Large-span steel truss high-altitude integral variable-angle jacking construction method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN114809310A CN114809310A (en) | 2022-07-29 |
| CN114809310B true CN114809310B (en) | 2022-09-27 |
Family
ID=82520752
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210720064.3A Active CN114809310B (en) | 2022-06-24 | 2022-06-24 | Large-span steel truss high-altitude integral variable-angle jacking construction method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114809310B (en) |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| BRPI0706980A2 (en) * | 2006-02-07 | 2011-04-12 | Mauro Baschieri | single span free span suspended bridge |
| CN102926546A (en) * | 2012-11-28 | 2013-02-13 | 中国建筑第八工程局有限公司 | Installation method of inclined net rack of roof |
| CN110820950A (en) * | 2019-10-31 | 2020-02-21 | 中建六局第三建筑工程有限公司 | Integral synchronous jacking construction method for large-span combined type overweight eccentric slope angle steel structure |
| CN210563435U (en) * | 2019-07-12 | 2020-05-19 | 中建八局第二建设有限公司 | Slope supporting device for top rising of inclined heavy-load steel net rack |
| CN111980165A (en) * | 2020-08-07 | 2020-11-24 | 中建八局第二建设有限公司 | Large-span net rack external-expanding splicing integral jacking construction method |
| CN113833279A (en) * | 2021-10-28 | 2021-12-24 | 中国一冶集团有限公司 | Integral jacking construction method for deformed steel net rack with height difference during mounting of support |
-
2022
- 2022-06-24 CN CN202210720064.3A patent/CN114809310B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| BRPI0706980A2 (en) * | 2006-02-07 | 2011-04-12 | Mauro Baschieri | single span free span suspended bridge |
| CN102926546A (en) * | 2012-11-28 | 2013-02-13 | 中国建筑第八工程局有限公司 | Installation method of inclined net rack of roof |
| CN210563435U (en) * | 2019-07-12 | 2020-05-19 | 中建八局第二建设有限公司 | Slope supporting device for top rising of inclined heavy-load steel net rack |
| CN110820950A (en) * | 2019-10-31 | 2020-02-21 | 中建六局第三建筑工程有限公司 | Integral synchronous jacking construction method for large-span combined type overweight eccentric slope angle steel structure |
| CN111980165A (en) * | 2020-08-07 | 2020-11-24 | 中建八局第二建设有限公司 | Large-span net rack external-expanding splicing integral jacking construction method |
| CN113833279A (en) * | 2021-10-28 | 2021-12-24 | 中国一冶集团有限公司 | Integral jacking construction method for deformed steel net rack with height difference during mounting of support |
Also Published As
| Publication number | Publication date |
|---|---|
| CN114809310A (en) | 2022-07-29 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103866986B (en) | Long span variable cross-section bolted spherical node net shell mounting method | |
| CN107090932A (en) | Large span thin-walled planar based on stiffness ring beam encircles the construction method of truss | |
| CN108316479B (en) | Truss arch system and construction method thereof | |
| CN109853404A (en) | Steel truss girder bridge cantilever assembly erection method | |
| CN109763568B (en) | Suspended dome grid structure construction method | |
| CN110965470A (en) | Main tower cross brace structure system capable of bearing three-way load and construction method | |
| CN111608078B (en) | Construction method of combined Bailey cable crane tower | |
| CN112081016A (en) | Lifting and folding device for bridge arch rib | |
| CN110820950B (en) | Integral synchronous jacking construction method for large-span combined type overweight eccentric slope angle steel structure | |
| CN111218987A (en) | Bearing type net rack construction method | |
| CN111980165A (en) | Large-span net rack external-expanding splicing integral jacking construction method | |
| CN114809310B (en) | Large-span steel truss high-altitude integral variable-angle jacking construction method | |
| CN113186836A (en) | Construction method of brand-new prestress integral bridge falsework | |
| CN113175089A (en) | Construction method of large-span heavy cantilever truss | |
| CN113322813A (en) | Method for solving synchronous pushing of large-span steel concrete composite beam by using cable-stayed tower | |
| CN110700416B (en) | Large-span net rack integral jacking method and limiting and anti-tipping device thereof | |
| CN102635061B (en) | Mountain stream river-crossing cable-stayed chain trestle and hoisting method thereof | |
| CN112411760B (en) | Construction method for integrally hoisting and combining cantilever installation of head unit | |
| CN205369948U (en) | Lifting device for daylighting top is used for installing | |
| CN112502473B (en) | Supporting bearing capacity conversion device and method for dismantling large steel framework by using same | |
| CN112112284A (en) | Integral jacking construction method for net rack | |
| CN113152768A (en) | Unequal-diameter ring truss high-altitude sectional installation fixing device | |
| CN207633791U (en) | A kind of free-standing temporary support for curved tube component | |
| CN206544855U (en) | Supporting apparatus for large spatial structure construction elevator wall-attached frame | |
| CN220120401U (en) | Climbing process test device of internal climbing tower crane |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| EE01 | Entry into force of recordation of patent licensing contract | ||
| EE01 | Entry into force of recordation of patent licensing contract |
Application publication date: 20220729 Assignee: TIANJIN SHUANGCHUANG TECHNOLOGY CO.,LTD. Assignor: Tianjin Medical University Contract record no.: X2024980002721 Denomination of invention: Construction method of high-altitude overall variable angle jacking for large-span steel grid structures Granted publication date: 20220927 License type: Common License Record date: 20240312 |