CN115559226A

CN115559226A - Prepressing construction method of upward and self-propelled movable formwork

Info

Publication number: CN115559226A
Application number: CN202211228684.1A
Authority: CN
Inventors: 袁义华; 平栓玲; 荔大江; 邹明; 郭炜欣; 高凯恒; 张洪鹏; 邵文亮; 单云浩; 张云鹤; 陈扬; 汪航; 孙浩铭
Original assignee: Fourth Engineering Co Ltd of China Railway Seventh Group Co Ltd; China Railway Seventh Group Co Ltd
Current assignee: Fourth Engineering Co Ltd of China Railway Seventh Group Co Ltd; China Railway Seventh Group Co Ltd
Priority date: 2022-10-08
Filing date: 2022-10-08
Publication date: 2023-01-03
Also published as: LU503914B1

Abstract

The invention discloses an upward self-propelled moving formwork prepressing construction method, when prepressing is carried out on a moving formwork, sand bags and concrete precast blocks are adopted as load forms, the number of the concrete precast blocks is increased by lifting according to the difference of the section shape of a box girder and the clamping proportion of prepressing load, the concrete precast blocks are uniformly arranged and paved layer by layer along the bridge direction, the concrete precast blocks are arranged into two structures including an A-type precast block and a B-type precast block, the concrete precast blocks are convenient to stack and perform standardized prefabrication, a slotted hole is formed in the middle of the top, and a U-shaped or straight-shaped steel bar is arranged in the slotted hole, so that the concrete precast blocks are convenient to lift and lift, and the efficiency of prepressing loading construction is greatly improved on the whole.

Description

Prepressing construction method of upward and self-propelled movable formwork

Technical Field

The invention relates to the technical field of bridge construction. More specifically, the invention relates to an upward self-propelled movable formwork prepressing construction method.

Background

The movable formwork is a construction mechanical structure with a formwork, a bearing platform or a pier column is used as a support to pour a bridge in place, the construction mechanical structure is widely applied to continuous beam construction of highway bridges and railway bridges, prepressing is required after the movable formwork is assembled to eliminate inelastic deformation of the assembly of the movable formwork, elastic deformation during construction load is measured, pre-camber of a bottom formwork of the movable formwork is calculated according to upper camber of a box girder after being tensioned, safety performance of the formwork can be simultaneously checked through prepressing, however, sand bags or water bags are adopted in the prepressing process at present, forms of the sand bags and the water bags are relatively difficult to control, particularly, the water bags have risks of bag breakage, after prepressing weights required in different areas of the box girder are calculated, the weights need to be increased during grading prepressing, the sand bags or the water bags have the problem of difficult stable stacking, and the position adjustment by using a lifting trolley on the movable formwork is difficult, so that the whole prepressing construction efficiency is low.

Disclosure of Invention

An object of the present invention is to solve at least the above problems and to provide at least the advantages described later.

The invention also aims to provide an upward and self-propelled movable formwork prepressing construction method to solve the technical problems of inconvenient prepressing construction and low efficiency of the movable formwork in the prior art.

In order to achieve the objects and other advantages according to the present invention, an upward self-propelled moving formwork prepressing construction method is provided, wherein the moving formwork is prepressed by using a concrete precast block and sand bags, the beam end is arranged to have a high span-middle low equal load effect according to the section shape of the box girder, the flange plate corresponding to the box girder is prepressed by using the sand bags in the section direction of the box girder, and the web plate, the top plate and the bottom plate corresponding to the box girder are prepressed by using the concrete precast blocks.

Preferably, the concrete precast block comprises a class A precast block and a class B precast block, and the class A precast block and the class B precast block are C20 concrete precast blocks and are respectively quadrangular.

Preferably, the length of the bottom side of the class A pre-pressing block is 120cm, the height of the bottom side of the class B pre-pressing block is 75cm, the length of the bottom side of the class A pre-pressing block is 120cm, the height of the bottom side of the class B pre-pressing block is 30cm, square slotted holes with the length of 20cm are respectively formed in the centers of the tops of the class A pre-pressing block and the class B pre-pressing block downwards, two U-shaped steel bars are arranged in the slotted holes of the class A pre-pressing block downwards in an aligned central line mode, the two U-shaped steel bars are perpendicularly arranged in a horizontal plane in a crossed mode, the length of each end of each U-shaped steel bar is 50cm, the length of each middle of each U-shaped steel bar is 80cm, the height difference between the tops of the U-shaped steel bars and the tops of the slotted holes is 10cm, two straight-shaped steel bars are perpendicularly arranged in the slotted holes of the class B pre-pressing block in an aligned central line mode in the horizontal direction in a crossed mode, the straight-shaped steel bars are 100cm in length, and the height difference between the tops of the slotted holes is 10cm.

Preferably, the pre-pressing load is divided into three stages according to 60%, 100% and 120% of the maximum construction load, the three-stage loading and load holding time is not less than 2h, 2h and 8h respectively, the movable mould frame is subjected to settlement observation in the pre-pressing process, and deformation stability is determined when the difference of the observed deformation values is less than 2 mm.

Preferably, 32m of box girders are cast in situ on the movable formwork, the box girders are divided into three areas along the length direction, the first areas are symmetrically arranged at two ends of the box girders and have the length of 1.5m, the second areas are symmetrically arranged at the inner sides of the first areas and have the length of 3m, a third area is arranged between the two second areas, and the first, second and third areas are respectively preloaded by 60%, 100% and 120% of the maximum construction load.

Preferably, the weight of each sand bag is set to be 1.5t, when the web plate, the top plate and the bottom plate of the corresponding box girder are pre-pressed by the concrete precast blocks, the A-type pre-pressing blocks are arranged in a priority mode, the rest load is recycled, the B-type pre-pressing blocks are complemented, all the A-type pre-pressing blocks and the B-type pre-pressing blocks on each layer are uniformly placed, and the symmetry axes are aligned to the forward bridge direction.

Preferably, stack during the A type pre-compaction piece, through setting up supplementary positioning platform auxiliary adjustment A type pre-compaction piece is at the ascending horizontal position of horizontal bridge, and supplementary positioning platform sets up and is corresponding box girder top, bottom plate department middle part and be located same horizontal plane on the A type pre-compaction piece, include:

the platform plate is of a horizontally arranged square structure, the width and the length of the platform plate at least cover 2A-type pre-pressing blocks, the bottom surface of the platform plate is a slip surface, a first partition plate is downwards arranged in the middle of the platform plate, a downwards telescopic jacking oil cylinder is arranged in the first partition plate, the telescopic end of the jacking oil cylinder is connected with a second partition plate, the second partition plate is consistent with the first partition plate in size, universal wheel sets are respectively arranged on the left side and the right side of the first partition plate and the second partition plate in the bridge direction, the thicknesses of the first partition plate and the universal wheel sets on the two sides in the bridge direction are 2 adjacent to the middle of the first partition plate, the arrangement intervals of the A-type pre-pressing blocks are consistent, and hooks are arranged at the edge of the top surface of the platform plate;

the elastic air bags are respectively arranged downwards at two ends of the horizontal bridge direction of the platform plate, extend along the bridge direction and downwards extend to the bottom of the A-type prepressing block, and the top corners of the platform plate are provided with air inlets communicated with the elastic air bags corresponding to the elastic air bags, and the air inlets are connected with an inflator pump;

the limiting assemblies are symmetrically arranged at the bottom of the platform plate, each limiting assembly comprises four limiting grooves which are formed by extending along the diagonal direction of the platform plate, each limiting groove corresponds to one of the groove holes, each limiting groove is divided into two layers which are communicated up and down, the width of the upper layer is larger than that of the lower layer, the lower layer of each limiting groove is connected with a vertically-arranged limiting rod in a sliding mode, the upper ends of the limiting rods are coaxially connected with a rotating motor, the rotating motor is fixed through a support, the supports are located in the upper layers of the limiting grooves, the two ends of each support are symmetrically provided with walking mechanisms, the limiting rods are driven to move along the extending direction of the limiting grooves on the upper layers of the limiting grooves, the limiting rods extend downwards out of the limiting grooves, the extending lengths of the limiting rods are smaller than the depth of the groove holes, the lower ends of the limiting rods are outwards provided with transverse rods along the horizontal direction, and the lengths of the transverse rods are smaller than 5cm;

the control system comprises a control terminal, a control chip and a camera module which is fixed at the bottom of the platform board and is arranged at one side close to the limiting groove, the control chip and the camera module are respectively in communication connection with the control terminal, and the control chip is also electrically connected with the rotating motor, the walking mechanism and the inflator pump;

the concrete precast block is along following the bridge to placing two at one deck middle part behind the concrete precast block, through lifting by crane dolly on the moving die carrier mentions whole supplementary positioning platform along with follow the bridge to the axis align and transfer two in the middle part on the concrete precast block, and first baffle, second baffle are located two between the interval hole of concrete precast block, transfer the in-process, observe through camera module the position of slotted hole to send control signal to control chip through control terminal, adjust rotating electrical machines, running gear, so that gag lever post and horizontal pole are located the transverse range of slotted hole is avoided U type reinforcing bar or straight reinforcing bar, the elasticity gasbag of tip are located the below between concrete precast block and the outside between the concrete precast block, later start the pump through control chip, inflate the elasticity gasbag of both sides, produce the extrusion force of cross bridge in the inflation process, promote the cross bridge to be located the platform outside adjacent the concrete precast block is close to the web of case roof beam and removes conflict backward two the concrete precast block is accomplished with universal wheelset, adjusts the back through the wheel set, sends the elasticity gasbag through control after the control to lifting by crane again and removes the platform and removes the position again.

Preferably, the elastic airbag includes a plurality of balls arranged in a matrix along a vertical plane, a straight portion is communicated between adjacent balls, and a width of the straight portion is smaller than a diameter of the ball.

The invention at least comprises the following beneficial effects: the invention relates to an upward self-propelled moving formwork prepressing construction method, which aims at prepressing the moving formwork, adopts sand bags and concrete precast blocks as load forms, and according to the difference of the section shape of a box girder and the prepressing load clamping proportion, the number of the concrete precast blocks is hoisted and increased, the concrete precast blocks are uniformly arranged and paved layer by layer along the bridge direction, the concrete precast blocks are arranged into two structures including an A-type precast block and a B-type precast block, the concrete precast blocks are convenient to stack and perform standardized prefabrication, a slotted hole is formed in the middle of the top, a U-shaped or straight reinforcing steel bar is arranged in the slotted hole, the hoisting of the concrete precast blocks is convenient, in addition, an auxiliary positioning platform is arranged to assist in adjusting the position of the concrete precast block on the same layer, the occupation of equipment for hoisting the concrete precast blocks can be relieved as soon as possible, and the prepressing loading construction efficiency is greatly improved as a whole.

Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention.

Drawings

FIG. 1 is a schematic structural view of a moving die carrier of the present invention during preloading;

FIG. 2 is a schematic view of the distribution of the preload in the forward direction of the bridge according to the present invention;

FIG. 3 is a top view of the class A pre-compact of the present invention;

FIG. 4 is a side view of the type A pre-compact of the present invention;

FIG. 5 is a top view structural diagram of a class B pre-press block of the present invention;

FIG. 6 is a side view structural diagram of a class B pre-press block of the present invention;

FIG. 7 is a schematic structural diagram of an auxiliary positioning platform according to the present invention;

FIG. 8 is a top view of the structure of the stop lever of the present invention before it enters the slot;

FIG. 9 is a top view of the structure of the position limiting rod of the present invention after entering the slot.

The specification reference numbers: 1. a movable mould frame, 2 and A type prepressing blocks, 3 and B type prepressing blocks, 4, slotted holes, 5, U-shaped steel bars, 6, straight steel bars, 7, a platform plate, 8, a first clapboard, 9, a pushing oil cylinder, 10, a second clapboard, 11 and a universal wheel group, 12, a hook, 13, an elastic air bag, 14, an air inlet, 15, a limiting groove, 16, a limiting rod, 17, a camera module, 18, a ball part, 19, a straight part, 20, a hoisting trolley, 21, a template, 22, a sand bag, 23 and a cross bar.

Detailed Description

The present invention is further described in detail below with reference to the attached drawings so that those skilled in the art can implement the invention by referring to the description text.

It is to be noted that the experimental methods described in the following embodiments are all conventional methods unless otherwise specified, and the reagents and materials, if not otherwise specified, are commercially available; in the description of the present invention, the terms "lateral", "longitudinal", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, are only for convenience in describing the present invention and simplifying the description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention.

As shown in fig. 1-9, the invention provides a prepressing construction method of an upward self-propelled movable formwork, which is characterized in that a prepressing mode of a concrete precast block and a sand bag 22 is adopted on the movable formwork 1, and the prepressing is arranged into equal load effects of high beam end, middle span and low beam according to the section shape of a box girder, in the section direction of the box girder, a flange plate corresponding to the box girder is prepressed by the sand bag 22, and a web plate, a top plate and a bottom plate corresponding to the box girder are prepressed by the concrete precast block.

During preloading, the stress state of the box girder during construction is simulated as much as possible, the concrete precast block and the sand bag are pre-pressed, the sand bag is bagged and then transported to a platform by a vehicle, the crane is used for hoisting the box girder to go to the bridge, the sand bags are stacked in layers, the box girder is arranged to be high in beam end according to the section shape of the box girder, the equal-load effect of the middle-low span is pre-pressed, the pre-pressing mode of the concrete precast block is adopted, the load condition during pre-pressing loading is easier to adjust, meanwhile, the concrete precast block serving as the load can be manufactured in a standardized mode, and the manufacturing and production cost are reduced.

In another technical scheme, as shown in fig. 1 to 7, the concrete precast block includes a class a pre-pressed block 2, a class B pre-pressed block 3,A, and a class B pre-pressed block 3, which are C20 concrete precast blocks and are quadrangular respectively.

Two kinds of quadrangular prism-shaped prepressing blocks are designed according to the size of the box girder for balancing weight, so that the combination of adjustment and weight is convenient, the expected prepressing load capacity is ensured, and the orientation of the prepressing blocks does not need to be frequently adjusted.

In another technical scheme, as shown in fig. 1-7, the side length of the bottom surface of the a-type pre-pressing block 2 is 120cm and the height of the bottom surface of the B-type pre-pressing block 3 is 75cm, the side length of the bottom surface of the B-type pre-pressing block 3 is 120cm and the height of the bottom surface of the B-type pre-pressing block 3 is 30cm, square slotted holes 4 with the side length of 20cm are respectively formed downwards in the centers of the tops of the a-type pre-pressing block 2 and the B-type pre-pressing block 3, two U-shaped steel bars 5 are arranged in a horizontal plane in an aligned and downward manner, the two ends of each U-shaped steel bar 5 are 50cm long and 80cm long in the middle, the height difference between the top of each U-shaped steel bar 5 and the top of each slotted hole 4 is 10cm, two straight-shaped steel bars 6 are arranged in a aligned and vertically crossed manner along the horizontal direction in the slotted hole 4 of the B-type pre-pressing block 3, each straight-shaped steel bar 6 is 100cm long and 10cm high difference between the top of each slotted hole 4 is 10cm.

Through the size of design concrete prefabricated section, set up slotted hole 4 at the middle part of every concrete prefabricated section, set up the reinforcing bar that transversely runs through slotted hole 4 again, according to the difference of concrete prefabricated section height, set up to U type reinforcing bar 5 or straight type reinforcing bar 6 respectively, the structural strength of reinforced concrete prefabricated section on the one hand, on the other hand is convenient for lift by crane.

In another technical scheme, as shown in fig. 1, the preloading load is divided into three stages according to 60%, 100% and 120% of the maximum construction load, the three-stage loading and holding time is not less than 2h, 2h and 8h respectively, the movable formwork 1 is subjected to settlement observation in the preloading process, and deformation stability is determined when the difference of the observed deformation values is less than 2 mm.

Simulating the cast-in-place process of each box girder, and carrying out actual loading to verify the bearing capacity, wherein the loads are sequentially added one by one, the observation time (or unloading time) is long, the loads are loaded and unloaded in a grading manner, and after the grading standing time, the elevation value of each measuring point is measured; after each stage of loading is finished, observation is needed once per hour, the change value of the pre-pressing observation point is measured after each stage of loading is static, the deformation is considered to be stable when the observed deformation is not more than 2mm, the loading is continued after analysis, and the deformation is considered to be stable when the load is kept for 8 hours after all the loading is finished and the difference between the deformation values observed for the last two times is less than 2 mm.

In another technical scheme, as shown in fig. 1-2, a 32m box girder is cast on the movable formwork 1 in situ, the box girder is divided into three regions along the length direction, wherein the first region is symmetrically located at two ends of the box girder and has a length of 1.5m, the second region is symmetrically located at the inner side of the first region and has a length of 3m, a third region is arranged between the two second regions, and the first region, the second region and the third region are respectively preloaded with 60%, 100% and 120% of the maximum construction load.

And (3) load calculation: 32m box girder design weight 758.4t, in order to simulate actual construction working conditions, the box girder steel bar weight is about 70.5t, the box girder actual weight is 828.9t, two ends of a simply supported girder are located right above a pier, the first area is calculated according to the range of 1.5m, the weight is 54.8t (single side), the length of the second area is 3m, the weight is 89.3t (single side), the length of the third area is 23.6m, the weight is 270.8t (half), 830t is taken for pre-pressing calculation, the internal model weight 32t in the formwork 1 is moved, various construction loads are about 5t (artificial load, mechanical load and the like), and the pre-pressing load = (beam weight + internal model weight + construction load) = 1.2= (830 +32+ 5) × (1040.4 t).

In another technical scheme, as shown in fig. 1, the sand bag 22 is set to have a single weight of 1.5t, when the web plate, the top plate and the bottom plate of the corresponding box girder are pre-pressed by concrete precast blocks, the a-type pre-pressed blocks 2 are arranged in a preferential arrangement, the rest load is complemented by the B-type pre-pressed blocks 3, all the a-type pre-pressed blocks 2 and the B-type pre-pressed blocks 3 of each layer are uniformly arranged, and the symmetry axes are aligned with the bridge direction.

Specifically, the loading scheme is as follows, based on the weights calculated in the preceding scheme:

the A-type prepressing blocks 2 and the B-type prepressing blocks 3 on each layer are arranged along the bridge direction.

In the first area, when 60% of the maximum construction load is used for preloading, 221.8 sand bags are arranged on one side of a flange plate, 3A type prepressing blocks 2 are uniformly prepressed on one side of a web plate, the A type prepressing blocks 2 are arranged in three layers upwards, 1 block is arranged on each layer, and 1B type precast block is arranged on the fourth layer; 4 even pre-compaction of unilateral of top, bottom plate A type pre-compaction piece 2, 2B type pre-compaction

piece

3, 4 of top, bottom plate unilateral A type pre-compaction piece 2 is arranged 2 rows along the bridge direction, every 2 layers, every 1 piece on layer, 1 is placed at the top on every row B type pre-compaction piece 3.

In the first area, when 100% of the maximum construction load is used for preloading, 223 sand bags are arranged on one side of a flange plate, 6A-type prepressing blocks 2 are uniformly prepressed on one side of a web plate, 8A-type prepressing blocks 2 and 1B-type prepressing block 3 are uniformly prepressed on one sides of a top plate and a bottom plate, 6A-type prepressing blocks 2 on one side of the web plate are arranged upwards for 6 layers, and 1 sand bag is arranged on each layer; 8 blocks on the single sides of the top plate and the bottom plate 2 are arranged in 2 rows along the bridge direction, 4 layers of each row and 1 block of each layer are arranged, and 1 block is placed on the 5 th layer on the single sides of the top plate and the bottom plate 3 of the B type.

In the first area, when 120% of the maximum construction load is used for preloading, 223.5 sand bags are arranged on one side of a flange plate, 7A-type prepresses 2 and 1B-type prepresses 3 are uniformly prepressed on one side of a web plate, 10A-type prepresses 2 are uniformly prepressed on one sides of a top plate and a bottom plate, 7A-type prepresses 2 on one side of the web plate are arranged upwards for 7 layers, and 1B-type prepressing 3 is placed on the 8 th layer; 10 prepressing blocks 2 of the A type are uniformly arranged on the single sides of the top plate and the bottom plate along the bridge direction, and 2 blocks are arranged in 5 layers and 2 layers in each row.

In a second area, when 60% of maximum construction load is used for preloading, 223.5 sand bags are arranged on one side of a flange plate, 5A type prepresses 2 and 2B type prepresses 3 are uniformly prepressed on one side of a web plate, 7A type prepresses 2 and 1B type prepresses 3 are uniformly prepressed on a top plate and a bottom plate, 2 layers, 3 layers, 2 layers and 2B type prepresses 3 are uniformly arranged on the 3 rd layer of the 5A type prepresses 2 on one side of the web plate; 7 of top, bottom plate 2 are arranged 2 rows along following the bridge to A type pre-compaction

piece

2, 1 layer in every row, every

layer

3, 1 remains A type pre-compaction piece 2 and 1B type pre-compaction piece 3 evenly places on the 2 nd floor of top, bottom plate.

In the second region, when 100% pre-compaction loading with the biggest construction load, the unilateral setting of flange board is 226 sand bags, the unilateral of web is 9 evenly pre-compaction A type pre-compaction piece 2, 1B type pre-compaction piece 3, top, the even pre-compaction 12 of bottom plate A type pre-compaction piece 2, 1B type pre-compaction piece 3. 9A-type prepressing blocks on one side of the web plate are arranged in 2 rows and 3 layers, 3A-type prepressing blocks on each layer, and 1B-type prepressing block 3 on the 3 rd layer; 12 blocks of the top plate and the bottom plate are arranged in 2 rows of the A-type prepressing blocks 2 along the bridge direction, 2 layers of 3 blocks are arranged in each row, 1 block of the B-type prepressing blocks 3 is placed on the 3 rd layers of the top plate and the bottom plate.

In a second area, when preloading is carried out by 120% of the maximum construction load, 227 sand bags are arranged on one side of a flange plate, 11A-type prepressing blocks 2 are uniformly prepressed on one side of a web plate, and 13A-type prepressing blocks 2, 1B-type prepressing block 3 are uniformly prepressed on a top plate and a bottom plate; 11A-type prepressing blocks on one side of the web plate are arranged in 2 rows and 4 layers, and each layer is provided with 3 blocks; 13 blocks of the top plate and the bottom plate are arranged in 2 rows along the bridge direction, 3 blocks are arranged in each row, 3 layers are formed, 1 block of the B-type prepressing block 3 is placed at the 3 rd layer vacant position of the top plate and the bottom plate.

In the third area, when preloading is carried out by 60% of the maximum construction load, 2228.2 sand bags are arranged on one side of a flange plate, 31A-type prepressing blocks 2 are uniformly prepressed on one side of a web plate, and 43A-type prepressing blocks 2 and 1B-type prepressing block 3 are uniformly prepressed on a top plate and a bottom plate; 31 blocks on one side of the web plate, 2 rows and 2 layers of the A-type precompresses, wherein, the 1 st layer is 19 blocks; 43 blocks of top and bottom plates 2 rows of A-type pre-pressed blocks are arranged along the bridge direction, 2 layers are arranged in each row, 19 blocks are arranged on the 1 st layer, and the

rest

2 and 1 blocks of A-type pre-pressed blocks and 3 blocks of B-type pre-pressed blocks are uniformly arranged on the 2 nd layer.

In the third area, when preloading is carried out by 100% of the maximum construction load, 2247 sand bags are arranged on one side of the flange plate, 50A type prepressing blocks 2 and 1B type prepressing block 3 are uniformly prepressed on one side of the web plate, and 72A type prepressing blocks 2 are uniformly prepressed on the top plate and the bottom plate; 50A-type prepressing blocks on one side of the web are arranged in 2 rows and 3 layers, each layer of 1 and 2 layers is 19, and 1B-type prepressing block 3 is placed at the vacant position of the 3 rd layer on one side of the web; 72 blocks of the top plate and the bottom plate are arranged in 2 rows of the A-type precompresses 2 along the bridge direction, each row has 2 layers, 19 blocks are arranged on the 1 st layer, and 17 blocks are arranged on the 2 nd layer.

In the third area, when 120% of the maximum construction load is used for preloading, 2256 sand bags are arranged on one side of the flange plate, 61 prepresses of the A-type prepressing

blocks

2 and 3 of the B-type prepressing blocks 3 are uniformly prepressed on one side of the web plate, and 87 prepresses of the top plate and the bottom plate are uniformly prepressed on the A-type prepressing blocks 2; 61A-type pre-pressing blocks 2 on one side of a web plate are arranged in 4 layers, 19 blocks are arranged on each layer, and the rest 4A-type pre-pressing blocks 2 and 3B-type pre-pressing blocks 3 on the 4 th layer are uniformly placed; 87 blocks of the A-type prepressing blocks 2 on the top plate and the bottom plate are arranged in 2 rows along the bridge direction, each row has 3 layers, each layer has 19 blocks, and the rest of the 3 rd layer of the A-type prepressing blocks 2 are uniformly placed.

In another technical scheme, as shown in fig. 7-9, when stacking the a-type pre-pressed blocks 2, the horizontal position of the a-type pre-pressed blocks 2 on the horizontal bridge is adjusted by setting an auxiliary positioning platform, and the auxiliary positioning platform is arranged on the a-type pre-pressed blocks 2 corresponding to the middle parts of the top and bottom plates of the box girder and located in the same horizontal plane, and includes:

the platform plate 7 is of a horizontally arranged square structure, the width and the length of the platform plate are at least 2, the A-type prepressing blocks 2 are covered, the bottom surface of the platform plate 7 is a slip surface, a first partition plate 8 is downwards arranged in the middle of the platform plate 7, a downwards telescopic jacking oil cylinder 9 is arranged inside the first partition plate 8, the telescopic end of the jacking oil cylinder 9 is connected with a second partition plate 10, the second partition plate 10 is consistent with the first partition plate 8 in size, universal wheel sets 11 are respectively arranged on the left side and the right side of the second partition plate 10 in the bridge direction, the first partition plate 8 and the universal wheel sets 11 on the two sides are consistent with the arrangement interval of the A-type prepressing blocks 2 adjacent to the middle in the thickness of the bridge direction, and hooks 12 are arranged on the edge of the top surface of the platform plate 7;

the elastic air bags 13 are respectively arranged downwards at two ends of the platform plate 7 in the transverse bridge direction, the elastic air bags 13 extend along the bridge direction and downwards extend to the bottom of the A-type prepressing block 2, air inlets 14 communicated with the elastic air bags 13 are arranged at the vertex angles of the platform plate 7 corresponding to the elastic air bags 13, and the air inlets 14 are connected with an inflator pump;

the limiting assemblies are symmetrically arranged at the bottom of the platform plate 7 and comprise four limiting grooves 15 which are formed in an extending mode along the diagonal direction of the platform plate 7, one limiting groove 15 corresponds to one slotted hole 4, the limiting grooves 15 are divided into two layers which are communicated up and down, the width of the upper layer is larger than that of the lower layer, the lower layer of each limiting groove 15 is connected with a vertically-arranged limiting rod 16 in a sliding mode, the upper end of each limiting rod 16 is coaxially connected with a rotating motor, the rotating motors are fixed through a support, the support is located in the upper layer of each limiting groove 15, two ends of each support are symmetrically provided with a traveling mechanism, the traveling mechanisms are used for driving the limiting rods 16 to move along the extending direction of the limiting grooves 15 on the upper layer of each limiting groove 15, the limiting rods 16 extend out of the limiting grooves 15 downwards, the extending length of the limiting rods 16 is smaller than the depth of the slotted holes 4, the lower ends of the limiting rods 16 are outwards provided with transverse rods 23 along the horizontal direction, and the length of the transverse rods 23 is smaller than 5cm;

the control system comprises a control terminal, a control chip and a camera module 17 which is fixed at the bottom of the platform plate 7 and is arranged at one side close to the limiting groove 15, the control chip and the camera module 17 are respectively in communication connection with the control terminal, and the control chip is also electrically connected with the rotating motor, the walking mechanism and the inflator pump;

two at the one deck middle part is being placed along following the bridge to behind the concrete prefabricated section, through lifting by crane dolly 20 on the moving die carrier 1 lifts whole supplementary positioning platform along with follow the bridge to the axis align and transfer two in the middle part on the concrete prefabricated section, and first baffle 8, second baffle 10 are located two between the interval hole of concrete prefabricated section, transfer the in-process, observe through camera module 17 slotted hole 4's position to send control signal through control terminal to control chip, adjust to rotating electrical machines, running gear, so that gag lever post 16 and horizontal pole 23 are located the transverse range of slotted hole 4 is interior and avoid U shaped steel muscle 5 or straight reinforcing bar 6, the elasticity gasbag 13 of tip is located the below concrete prefabricated section and the outside between the concrete prefabricated section, later start the pump through control chip, inflate the elasticity gasbag 13 of both sides, produce the extrusion force of horizontal bridge to the inflation in-process, promote the horizontal bridge to be located adjacent in the concrete prefabricated section 7 outside the concrete prefabricated section is close to the removal of prefabricated box girder reverse promotion template two adjustment of prefabricated section and the adjustment of prefabricated section simultaneously the platform bottom is adjusted through the universal shrink control platform after, and is accomplished the whole supplementary positioning platform along the telescopic control chip again, and is carried out the position after the removal of lifting by crane the flexible gasbag, and is carried out the removal of the whole.

After a layer of A-type prepressing blocks 2 is placed, the transverse positions of the A-type prepressing blocks 2 or the B-type prepressing blocks 3 adjacent in the horizontal direction are adjusted through the arranged auxiliary positioning platform, the limitation on a concrete precast block hoisting device can be relieved more quickly, the adjustment requirement on the concrete precast blocks is reduced, particularly the problem that the hoisting device is inconvenient to adjust for high-altitude construction is solved, the hoisting efficiency of the whole prepressing load material is improved, the elastic air bag 13 is arranged in a vertical surface and extends along the bridge direction, a sealing ring and other materials can be arranged at the air inlet 14 to facilitate the sealing of an air inlet channel, air is introduced into the elastic air bag 13, the elastic air bag 13 expands until the concrete precast blocks (the A-type prepressing blocks 2 or the B-type prepressing blocks 3) abutting the left side and the right side begin to generate transverse bridge direction extrusion force on the concrete precast blocks to form thrust force, when the weight of the concrete precast block at the bottom of the platform plate 7, the platform plate 7 and the equipment pressure on the platform plate 7 are enough, 2 a-type pre-pressed blocks 2 positioned at the outer side of the platform plate 7, namely the outer side in the left and right directions as shown in fig. 4, are pushed to be close to the web template 21 to a required position, and after the pushing force is larger and the a-type pre-pressed block 2 at the web is pushed to be the required position, the elastic air bag 13 may play a certain role in jacking the whole platform plate 7 to counteract partial gravity of the platform plate 7, so as to push two a-type pre-pressed blocks 2 positioned at the bottom of the platform plate 7, the two a-type pre-pressed blocks 2 are pushed to be closest, namely mutually abutted on the universal joint 11 of the first partition plate 8, and along with the increase of the number of layers of the concrete wheel set precast block, the pushing oil cylinder 9 can extend downwards out of the second partition plate 10 to be positioned between the 2 adjusted a-type pre-pressed blocks 2 at a layer at the bottom, further improve the direction linearity that pushes away the precast concrete piece through elasticity gasbag 13, and because the universal wheel group 11 that sets up, make landing slab 7 be convenient for along following the bridge to the removal, or be convenient for the downstream movement of second baffle 10, the spacing subassembly that sets up, spacing groove 15 has certain length, make gag lever post 16 can adapt to the size of slotted hole 4 and the position of A type pre-compaction piece 2 to a certain extent, when the slotted hole 4 of A type pre-compaction piece 2 in landing slab 7 bottom is not complete better alignment, acquire the picture of bottom and transmit for control terminal through camera module 17, then to the running gear if have driving motor's walking wheel, only need satisfy the removal function, adjust, gag lever post 16 whole can move along the oblique diagonal of landing slab 7, and according to U type reinforcing bar 5 or straight reinforcing bar 6's position, drive rotating motor rotation by a small margin, make horizontal pole 23 can avoid, horizontal pole 23 sets up to 5 cm's size, after the gag lever post 16 completely gets into in landing slab 4, cooperate rotating motor and running gear's adjustment, make horizontal pole 23 be located U type reinforcing bar 5 or straight reinforcing bar 6's position, thereby the lift force below the middle part of straight reinforcing bar 6 also can be restricted from the elastic airbag 7 of the lifting force and carry out the adjustment of the U type reinforcing bar 7, thereby the lifting force of the lifting force subassembly of the landing slab 7 is carried out on the real-type reinforcing bar and the real-time carries out the observation of the lifting force and can be set up and carry out on the lifting force of the landing slab from the straight reinforcing bar 1 in real-type reinforcing bar 1 in real-time, the landing slab 7, and carry out the straight reinforcing bar 1, and carry out the adjustment of the straight reinforcing bar.

In another technical solution, as shown in fig. 7, the elastic airbag 13 includes a plurality of ball portions 18 arranged in a matrix in a vertical plane, a straight portion 19 is communicated between adjacent ball portions 18, and a width of the straight portion 19 is smaller than a diameter of the ball portions 18. The combination of the ball portion 18 and the straight portion 19 is provided to facilitate control of the volume and orientation of the expansion on the one hand and to increase the contact area between the elastic air bag 13 and the concrete precast block to some extent on the other hand.

While embodiments of the invention have been described above, it is not intended to be limited to the details shown, described and illustrated herein, but is to be accorded the widest scope consistent with the principles and novel features herein disclosed, and to such extent that such modifications are readily available to those skilled in the art, and it is not intended to be limited to the details shown and described herein without departing from the general concept as defined by the appended claims and their equivalents.

Claims

1. The prepressing construction method of the upward self-propelled movable formwork is characterized in that prepressing is carried out on the movable formwork in a prepressing mode of concrete precast blocks and sand bags, the equal load effects of high beam ends and low span are arranged according to the section shape of a box girder, in the section direction of the box girder, flange plates corresponding to the box girder are prepressed by the sand bags, and web plates, top plates and bottom plates corresponding to the box girder are prepressed by the concrete precast blocks.

2. The upward self-propelled moving formwork prepressing construction method according to claim 1, wherein the concrete precast block comprises a class a prepressing block and a class B prepressing block, both the class a prepressing block and the class B prepressing block are C20 concrete precast blocks and are respectively quadrangular.

3. The upward and self-propelled moving formwork prepressing construction method according to claim 2, wherein the bottom side length of the class a prepressing block is 120cm and the height thereof is 75cm, the bottom side length of the class B prepressing block is 120cm and the height thereof is 30cm, square slotted holes with the side length of 20cm are respectively formed downwards at the centers of the tops of the class a prepressing block and the class B prepressing block, two U-shaped reinforcing bars are arranged downwards in the slotted holes of the class a prepressing block in alignment with the center line, the two U-shaped reinforcing bars are arranged in a horizontal plane in a mutually perpendicular and crossed manner, the two ends of the U-shaped reinforcing bar are 50cm long and the middle part thereof is 80cm long, the height difference between the tops of the U-shaped reinforcing bars and the tops of the slotted holes is 10cm, two straight reinforcing bars are arranged in the slotted holes of the class B prepressing block in alignment with the center line in a mutually perpendicular and crossed manner in the horizontal direction, the straight reinforcing bars are 100cm long and the height difference between the tops of the slotted holes is 10cm.

4. The upward-traveling self-traveling moving formwork prepressing construction method according to claim 3, wherein the prepressing load is divided into three stages according to 60%, 100%, 120% of the maximum construction load, the three-stage loading holding time is not less than 2h, 8h, respectively, the moving formwork is settled during the prepressing process, and the deformation is determined to be stable when the difference between the observed deformation values is less than 2 mm.

5. The upward-moving type movable formwork prepressing construction method according to claim 4, wherein 32m box girders are cast on the movable formwork in situ, the box girders are divided into three regions along the length direction, wherein the first region is symmetrically positioned at two ends of the box girders and has a length of 1.5m, the second region is symmetrically positioned at the inner side of the first region and has a length of 3m, a third region is arranged between the two second regions, and the first region, the second region and the third region are respectively preloaded with 60%, 100% and 120% of the maximum construction load.

6. The upward self-propelled moving formwork prepressing construction method according to claim 5, wherein a single weight of the sand bag is set to 1.5t, when a web plate, a top plate and a bottom plate of a corresponding box girder are prepressed by concrete precast blocks, the A-type prepressing blocks are arranged in a priority arrangement, the rest load is complemented by the B-type prepressing blocks, all the A-type prepressing blocks and the B-type prepressing blocks of each layer are uniformly arranged, and symmetrical axes are aligned to the bridge direction.

7. The upward-traveling movable formwork prepressing construction method according to claim 6, wherein when stacking the A-type prepressing blocks, the horizontal position of the A-type prepressing blocks in the transverse bridge direction is adjusted by arranging an auxiliary positioning platform, and the auxiliary positioning platform is arranged on the A-type prepressing blocks which are positioned in the same horizontal plane corresponding to the middle parts of the top and bottom plates of the box girder, comprising:

the elastic air bags are respectively arranged downwards at two ends of the horizontal bridge direction of the platform plate, extend along the bridge direction and extend downwards to the bottom of the A-type prepressing block, air inlets communicated with the elastic air bags are arranged at the vertex angles of the platform plate corresponding to the elastic air bags, and the air inlets are connected with an inflator pump;

8. The upward-traveling type moving formwork prepressing construction method according to claim 7, wherein the elastic air bag includes a plurality of ball portions arranged in a matrix in a vertical plane, a straight portion is communicated between adjacent ball portions, and a width of the straight portion is smaller than a diameter of the ball portion.